Stem cells have varying degrees of proliferation, self-renewal, and differentiation potential, and can be applied in regenerative medicine and the treatment of various diseases. To ensure safety and effectiveness of stem cell products, it is important to establish quality control methods and standards. Herein, we review the regulations and guidelines for stem cell products, and provide an overview of the detection assays on the basic biological characteristics, microbiological safety, biological safety, biological effectiveness and other conventional testing methods and quality research methods for stem cells. We further describe the quality research methods for genetically modified stem cell products, functional cells derived from stem cells, and extracellular vesicles, etc.

Thin layer chromatography (TLC) has been widely used for the separation and analysis of various constituents across multiple fields, owing to its advantages of cost-effectiveness, flexibility, high-throughput, and intuitiveness. Among the factors influencing TLC results, the choice of stationary phase critical. Currently, the main stationary phases used in TLC for identifying Chinese materia medica and Chinese patent medicines recorded in Chinese Pharmcopoeia, are silica gel, polyamide, and cellulose. This article reviews the characteristics and application of these three stationary phases in the analysis of Chinese herbal medicines. Using Chrysanthemi Indici Flos, Descurainiae Semen and Lepidii Semen, Oroxyli Semen, Cistanches Herba, Typhae Pollen, and Catechu as examples where traditional method are suboptimal, silica gel plates were employed to develop TLC identification methods with well-defined and abundant spots. These results highlight the clear advantages and feasibility of silica gel as a stationary phase in analyzing flavonoids and phenolic acid components. The findings offer alternative approaches to improve the national standards of these traditional Chinese medicines. Additionally, the article discusses the future development trend of TLC technology.

Objective: To explore the biological function methods of mesenchymal stem cells(MSCs) for quality analysis. Methods: The surface markers of MSCs were detected by flow cytometry. MSCs osteogenic differentiation was induced by ascorbic acid and β-glycerophosphate sodium, etc., followed by Alizarin Red S staining. MSCs adipogenic differentiation was induced by IBMX, Rosiglitazone, etc., followed by Oil Red O staining. MSCs could differentiate into chondrocytes with treatment of ITS and TGFβ3, etc., followed by Alcian Blue staining. Cell co-culture of THP-1-macrophage with MSCs and ELISA assay were applied to detect the effects of MSCs on macrophage polarization. The expression levels of IL-10 and TNF α in the cell co-culture supernatant were detected by ELISA. To observe the effects of MSCs on lymphocyte proliferation, MSCs cultured with PBMCs, which were labeled with CFSE and activated by CD3/CD28, followed by flow cytometry. Results: The expression of MSCs surface markers, CD105, CD73, and CD90, was more than 95% respectively, while the expression of CD45, CD34, CD14, CD19, and HLA-DR expression was less than 2%. MSCs osteogenic differentiation assay showed red calcium nodules. Red lipid vacuoles were observed in MSCs adipogenic induction differentiation. Furthermore, MSCs have the differentiation potential to chondrocyte spheroids, and typical cartilage pits were observed. Co-culture of MSCs with THP-1 macrophages, an increase in IL-10 expression and downregulate TNFα secretion were observed. MSCs played inhibitory effects on the proliferation of PBMC activated by CD3/CD28, with an inhibition rate of 76.4%. Conclusions: This study established some of biological activity detection methods for MSCs, including MSCs surface markers, differentiation abilities, promotion of macrophage polarization, and inhibitory effects on lymphocyte proliferation. It provides a potential application for MSCs products quality control.

Objective: To establish a simple and efficient method for detecting telomerase activity for evaluating tumorigenic risk of cell products. Methods: Specific primers and probes were designed for the conserved domain of telomerase catalytic subunit (TERT), and the primers and probes of TERT gene were optimized and screened, and the primers and probes of internal reference genes were set up. Multiple quantitative PCR reaction was performed using two-color fluorescent probes in a reaction system, and RT-qPCR probe method was established. The expression of TERT gene in human mesenchymal stem cells HMSC was used to determine whether telomerase activity existed in the cells indirectly. Results: TERT gene of 293T/17 positive control cells could be stably and specifically detected by this method, with a mean Ct value of 23.96 and a RSD of 1.5. The internal reference gene GAPDH could be detected successfully, the mean Ct value was 14.13, the RSD was 1.3%. The reference gene GAPDH in MRC-5 could be detected in negative control cells, the mean Ct value was 12.81, the RSD was 0.46%, the TERT gene was not detected, and the telomerase activity was negative. The reference gene GAPDH in HMSC could be detected, the Ct mean value was 13.01, and the RSD was 3.8%, whereas, the telomerase activity of HMSC was negative. Conclusion: The real-time fluorescent quantitative RT-qPCR probe method established in this study can accurately detect the expression of catalytic subunit mRNA in telomerase positive cells with good repeatability and high specificity. It can be used to analyze telomerase activity of stem cells and indirectly evaluate tumorigenic risk of cell products derived from stem cells.

Objective: To establish an in vitro permeation method for crisaborole ointment and to provide a reference for the bioequivalence of crisaborole ointment. Methods: The HPLC method was used to determine the permeability of crisaborole ointment, and the vertical Franz diffusion pool method was used to study the release characteristics of the ointment in vitro. The chromatographic column was Thermo BDS Hypersil-C₁₈(150 mm×4.6 mm, 5 μm), with 0.1% phosphoric acid solution-acetonitrile (60∶40) as the mobile phase, flow rate of 1.5 mL · min^-1, column temperature of 30 ℃, detection wavelength of 254 nm, and injection volume of 10 μL. Results: The peak shape of crisaborole in the chromatogram of the test sample was good. There was no peak at the position of crisaborole in the negative sample chromatogram, which did not interfere with the determination. The linear relationship of crisaborole was good within the range of 0.026-21.02 μg · mL^-1 (r≥0.999). In six repeated experiments, the mean maximum transmittance (J_max) of the self-made product and the reference formulation were compared (odds ratio: 0.94). Simultaneously calculate the confidence interval for J_max, with a 90% confidence interval ranging from 87.9% to 102.0%. The mass conservation percentage of each sample was 94.1%-101.1% (n=12). The reference solution was left at room temperature for 26 h, with a peak area RSD of 0.44%. The self-made product and reference preparation were left in a water bath at room temperature and 32 ℃ for 26 h, with peak area RSD ranging from 0.78% to 1.1%, indicating good stability of the solution. For the three batches of samples tested, the ratio of the mean J_max values of the self-made product and the reference formulation was within the range of 0.92-0.97. Simultaneously calculate the confidence interval for J_max, with a 90% confidence interval ranging from 84.8%-100.7%. Conclusion: This method is simple and convenient to operate, with high selectivity, strong exclusivity and high accuracy.

Objective: To establish the ultra performance liquid chromatography (UPLC) characterization profile of Styrax, and to determine the contents of three components (cinnamic acid, cinnamyl cinnamate, 3-phenylpropyl cinnamate) in Styrax, the aim was to study the quality of commercially available sulforaphane of different origins and forms, and to provide a reference for the quality control of imported medicinal herbs Styrax. Methods: The UPLC method was performed on an Acquity UPLC BEH C₁₈ (100 mm×2.1 mm, 1.7 µm) column with acetonitrile-1% acetic acid solution as the mobile phase in a gradient elution. The volume flow rate was 0.3 mL · min^-1. The detection wavelength was 277 nm. and the temperature of the column was 35 ℃. Characteristic chromatograms of styrax were established, and the contents of three major components of Styrax from different sources were determined and the data were statistically analyzed by hierarchical cluster analysis (HCA) and principal component analysis (PCA) with ChemPattern software. Results: The results showed that the UPLC characteristic chromatograms of Styrax was established with 10 common peaks and 4 identified components. The linear relationship of 3 components in their respective ranges was good (r≥0. 999), and the average recoveries (n=6) were 101.8% (RSD=1.3%), 105.8% (RSD=1.2%), 99.2% (RSD=1.8%), respectively. The content of 3 components were 2.74%-3.69%, 28.21%-30.63%, 16.89%-20.98%, respectively. Conclusion: The method is simple, accurate and reproducible, and can provide an overall quality control basis for the quality standard of Styrax. Combined with the information of origin research, it has important reference significance for the expansion of the origin of Styrax, as well as the harmonization and improvement of the standards of Styrax in different countries.

Objective: To employ adeno-associated viruses as vectors to design and prepare pseudoviruses comprising multiple DNA viral gene fragments. These were used as positive controls for the detection of human viruses in the field of molecular testing, thereby compensating for the absence of wild-type viral controls in viral molecular testing methods. Methods: The adeno-associated viral vectors served as the backbone of the pseudoviruses, with a total of four target gene fragments from three viruses incorporated: human papillomavirus type 16 (HPV16), type 18 (including HPV18-1 and HPV18-2) and human polyomavirus (HPyV) were, respectively, inserted into one viral vector, and the adeno-associated viral pseudoviruses were packaged by multiple plasmid cotransfection. The infectious activity of the pseudoviruses was confirmed by a cell infection assay, and a quantitative analysis of the pseudoviruses genome was conducted using fluorescence quantitative PCR. Results: The titers of HPV16, HPV18-1, HPV18-2, and HPyV genomes in the pseudoviruses were 7.77×10⁸ copies · mL^-1, 6.77×10⁸ copies · mL^-1, 7.04×10⁸ copies · mL^-1, and 1.24×10⁹copies · mL^-1, respectively, as determined by fluorescence quantitative PCR. Following a 48 h period of infection in 293T/17 cells, the viral gene sequences of HPV16, HPV18-1, HPV18-2, and HPyV were successfully identified using fluorescence quantitative PCR with the intracellular pseudoviruses. The copy numbers were 1.30×10⁶ copies · mL^-1, 6.59×10⁵ copies · mL^-1, 6.27×10⁵ copies · mL^-1, and 4.17×10⁶ copies · mL^-1. Following the infection of 293T/17 cells with the reporter gene pseudoviruses for a period of 48 hours, a distinct green fluorescence was evident under a fluorescence microscope, thereby confirming the infectious activity of the pseudoviruses. The pseudoviruses was employed as a positive control for the verification of applicability in human mesenchymal stem cells, and the recoveries of the four viral gene fragments by fluorescence quantitative PCR for nucleic acid extraction were 94.4%, 70.7%, 83.1% and 90.9%, respectively. Conclusion: The present study demonstrates that the adeno-associated virus packaging method can be employed to produce a multiviral gene pseudoviruses with infectious activity. The pseudoviruses can be employed as a positive control for the replacement of multiple wild-type viruses in the viral fluorescence quantitative polymerase chain reaction (PCR) of stem cell samples.

Objective: To establish the national standard materials of cyclosporine A, tacrolimus, sirolimus, and everolimus in frozen human whole blood. Methods: Anticoagulated whole blood samples were collected without obvious hemolysis, jaundice, or lipemia. The whole blood samples that had tested negative for four infectious diseases were pooled. They were frozen at - 20 ℃ for more than 48 h. After thawing, the samples were centrifuged at 4 000×g for 10 min, the precipitate was discarded, and pure raw materials of cyclosporine A, tacrolimus, sirolimus, and everolimus were added to prepare the target concentrations. The mixture was mixed thoroughly and then aliquoted into ampoules at two concentration levels. The homogeneity and stability of the standard materials were evaluated using one-way analysis of variance and linear regression methods. The assigned values were determined by reference methods, and uncertainty was calculated. Finally, the commutability of the standards was evaluated. Results: The F values of the homogeneity for cyclosporine A, tacrolimus, sirolimus, and everolimus at level I were 1.492 1,1.395 6, 1.432 8, and 1.060 2, respectively, and at level Ⅱ were 1.441 2, 1.476 1, 1.458 0, and 1.454 6, respectively. All of them were less than F_0.05. Level Ⅰ standard materials were stable for 10 d at 20-25 ℃ and 2-8 ℃, and for 30 d at - 20 ℃; Level Ⅱstandard materials were stable for 10 d at 20-25 ℃ and for 30 d at 2-8 ℃ and - 20 ℃. The assigned values of standard (k=2) were as follows: cyclosporine A level Ⅰwas (105.6±8.9) ng · mL^-1, level Ⅱ was (419.8±32.8) ng · mL^-1; tacrolimus level Ⅰwas (5.4±0.4) ng · mL^-1, level Ⅱ was (17.0±1.8) ng · mL^-1; sirolimus level Ⅰ was (5.0±0.3) ng · mL^-1, level Ⅱ was (15.7±1.1) ng · mL^-1; everolimus level Ⅰ was (4.8±0.2) ng · mL^-1, level Ⅱ was (10.2±0.6) ng · mL^-1. The two levels of standard concentration are within the 95% confidence interval of the regression line for fresh whole blood samples, indicating good commutability. Conclusion: The batch of the national standard material of cyclosporine A, tacrolimus, sirolimus, and everolimus in frozen human whole blood is homogeneous, stable, and commutable. The assigned values are accurate and reliable, and can be used as national standard for calibration of these four immunosuppressive agents, thereby promoting the standardization and consistency of test results.

Objective: To identify the structure and determine the source of unknown impurities present at levels greater than 0.1% in representative pharmaceutical excipient benzalkonium chloride samples, in accordance with ICH Q3A guidelines. Methods: A new LC-MS method suitable for the structure prediction of related substances of benzalkonium chloride was established. The separation was performed on an Acclaim 120 C₁₈ column (250 mm×4.6 mm, 5 μm) using a mobile phase consisting of methanol (mobile phase A) and 20 mmol · L^-1 ammonium formate aqueous solution (pH 3.5, mobile phase B) with gradient elution at a flow rate was 1 mL · min^-1. The post-column split was set to 1 ∶ 3. MS data were collected in positive ion mode using an electrospray ionization (ESI) source. The structures of unknown impurities were inferred using a “Diagnostic fragment ion extension strategy” and confirmed by comparing the chromatographic and mass spectrometric behaviors of the impurities with those of reference substances. Additionally, the source attribution and genotoxicity prediction of the detected impurities were performed. Results: A total of five unknown impurities were detected in a representative sample of benzalkonium chloride by the newly established LC-MS method, and their structures were inferred. The structures of four impurities were confirmed using two commercially available reference substances and two reference substances synthesized in a directionally oriented manner. Impurity D was identified as N-benzyl-N,N-dimethyl-1-phenylmethanaminium chloride. Impurity E as N-benzyl-N-methyl-1-phenylmethanamine. The impurity G as N-benzyl-N-methyldodecan-1-amine, and impurity H as N,N-dibenzyl-N-methyldodecane-1-ammonium chloride. Impurity F was hypothesized to be an isomer of the formula C₁₅H₁₇N. Predictions using Nexus 2.6.0 software indicated that all the above impurities fell into category 5 and had no genotoxic potential. Furthermore, the method successfully located four unknown impurities detected by the USP method in benzalkonium chloride related substances using impurity reference standards. Conclusion: This study systematically examines the structure and safety risks of potential impurities in benzalkonium chloride, providing valuable insights for enhancing quality control standards and pharmacopoeia criteria both domestically and internationally.

Human chorinonic gonadotropin (hCG) is an important regulator of reproductive and metabolic processes in the human body. hCG can be used for assisted reproduction and treatment of infertility. It is also used to treat sexual dysfunctions such as impotence, cryptorchidism, and dwarfism. hCG plays an irreplaceable role as an endocrine system drug. This article briefly describes the applications, molecular structure, receptor structure, signaling pathways and bioactivity assays of hCG. In addition, an outlook on the development of hCG drugs and bioactivity detection menthods is presented.

Objective: To study the bioactive components of the hypoglycemic effect of the traditional Chinese medicine Polygoni Cuspidate Rhizoma et Radix through its ability to inhibit α-glucosidase activity. Methods: Four modules: high-performance liquid chromatography system, the nanofraction collector, the channel of bioassay and high-resolution mass spectrometry were integrated to build a high-throughput bioassay profiling analysis platform. The preparative liquid chromatography was introduced to apply segmented enrichment to the extract of Polygoni Cuspidate Rhizoma et Radix, and the rapid screening of α-glucosidase inhibitors from Polygoni Cuspidate Rhizoma et Radix was realized by optimizing the chromatographic separation conditions, microfluidic fractionation collection parameters and bioassaying of enzyme activity in multi-well plates. Results: 28 α-glucosidase inhibitors were identified from Polygoni Cuspidate Rhizoma et Radix. The inhibitory activities of catechin-3-O-galloyl and procyanidin B₂-3''-O-gallate were determined with the IC₅₀ values of (9.49±1.93) μmol · L^-1 and (69.94±8.14) μmol · L^-1, respectively. Conclusion: This study has enabled high-throughput and high-resolution screening of α-glucosidase inhibitors in traditional Chinese medicine, providing a valuable tool for elucidating the active components and mechanisms of Polygoni Cuspidate Rhizoma et Radix to lower hyperglycemia.

Objective: To establish an HPLC-MS method for determination of three diastereoisomers in nirmatrelvir API. Methods: The analytical column was an InfinityLab Poroshell SB-C₁₈ (150 mm×3.0 mm,2.7 μm), the two columns connected in series in series. The mobile phase was buffer (0.1% formic acid) (A) -acetonitrile (B), the diluent was water-acetonitrile-methanol (61 ∶ 19.5 ∶ 19.5). The whole run carried out by gradient elution. The column temperature was 80 ℃,the injection volume was 2 μL, and the sample temperature was 5 ℃. Results: Nirmatrelvir was separated completely from three diastereoisomers (the resolution>1.5). The test solution was stable for at least 3 d. The LOQ of diastereoisomer 1 was 0.04%, the LOQ of diastereoisomer 2 was 0.04%, the LOQ of diastereoisomer 3 was 0.05%. The linear correlation coefficient of diastereoisomer 3 was >0.99. The linear range was LOQ-150% of specification. The average recovery (n=9) of diastereoisomer 3 was 97.2%, RSD = 3.1%. The repeatability and intermediate precision completely met the requirements. The three diastereoisomers contents in three batches of nirmatrelvir API 24 months long-term stability test were all completely met the requirements, respectively. Conclusion: This method is simple, rapid, sensitive and specific to be used for the determination of three diastereoisomers in nirmatrelvir API.

Objective: To explore the fragmentation patterns of etomidate analogues by mass spectrometry to provide reference for the identification and structural analysis of these substances. Methods: Etomidate, metomidate, propaxate and isopropaxate were analyzed by gas chromatography-quadrupole time-of-flight mass spectrometry (GC-Q TOF MS) and liquid chromatography high-resolution mass spectrometry (LC-Q Orbitrap MS) under EI and ESI positive ionization modes. And the EI-MS and ESI-MS/MS fragmentation patterns of etomidate analogues were deduced. Results: Etomidate and its analogues had similar fragmentation pathways. In EI-MS mode, the fragmentation pathway was mainly focused on the breaking of carbon-nitrogen bonds, and the specific fragment ions (m/z 105 and m/z 77) were formed. In ESI-MS/MS positive ion mode, the fragmentation pathway was mainly focused on the fracture of carbon-nitrogen bond, resulting in the formation of the characteristic fragment ion with styrene as neutral loss, Subsequently, the neutral fragments R₁ and H₂O were lost in turn, and the specific fragment ions (m/z 113 and m/z 95) was formed. Moreover, the neutral loss of R₁ in ESI-MS/MS positive ion mode could more intuitively indicate the substituents on the parent nucleus and further determine the structure of etomidate and its analogues. Conclusion: The fragmentation patterns of etomidate and its analogues are helpful to analyze and infer the structure of these substances, and provide reference for the identification and structural analysis of these substances in forensic laboratory.

Objective: To establish a new method for in situ visualization of spatial distribution characteristics of various secondary metabolites in the root of Wendang (Codonopsis pilosula Nannf. var. modesta (Nannf.) L. T. Shen), so as to realize the tissular localization of secondary metabolites, and to provide a reference for the in-depth excavation of the Wendang. Methods: Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) was used for the mass spectrometry imaging analysis of the root metabolites in Wendang. The matrix was DHB⁺/DHB^- (30 mg · mL^-1), the substrate flow rate was 20 μL · min^-1, the nitrogen flow rate was 5 L · min^-1, the nozzle movement speed was 3 mm · s^-1, the nozzle temperature was 60 ℃, and the spraying time of each slice was 50 min. The laser energy intensity in positive ion detection mode was 60%, and that in negative ion detection mode was 40%. The detection mass range was m/z 70-1 050, the mass resolution was 70 000, the spatial resolution was 50 μm, and the pixel size was 420 px×200 px. At the same time, the pathway enrichment analysis was also carried out for the metabolites. Results: A total of 214 metabolites were detected, and the spatial distribution characteristics of 40 representative metabolites were visualized. The distribution patterns of different kinds of secondary metabolites in the cork - phloem - xylem varied considerably, with flavonoids mainly distributed in xylem, alkaloids, phenolics, and carboxylic acids mainly in the cork and phloem, phenylpropanoids and quinones mainly in the cork, amino acids were abundant in the phloem, and nucleotides were distributed throughout the root tissues, the indicator components atractylenolide Ⅲ and syringoside were distributed in the cork, and lobetyolin was distributed in both the cork and the xylem. Pathway enrichment analysis showed that metabolites were significantly enriched in metabolic pathways, biosynthesis of secondary metabolites, flavonoid biosynthesis, biosynthesis of amino acids, and carbon metabolism pathways. Conclusion: This study visualizes the spatial distribution characteristics of metabolites in the roots of Wendang. The results of this study can provide certain theoretical support for the quality control, the identification, the extraction and separation of active ingredients, and the metabolic pattern of Wendang.

Objective: To establish a method to determination of the related substances and polymer impurities in cefminox sodium for injection. Method: Cefminox sodium was degraded in high temperature to prepare degradation solution. An RP-HPLC method for the related substances analysis was established with a Kromisil C₁₈ column (250 mm×4.6 mm, 5 μm), using 10 mmol · L^-1 phosphate buffer solution (pH 2.0)-acetonitrile (98∶2) (A)-acetonitrile (B) with gradient elution at a flow rate of 1.0 mL · min^-1. The column temperature was maintained at 25 ℃, the detection wavelength was set at 254 nm, and the injection volume was 20 μL. The specificity of RP-HPLC method and identification of unknown impurities was researched by 2D HPLC-MS/MS. Results: 14 main impurities were characterized in the degradation solution, including 3 cefminox dimmers and isomers which were characterized firstly. The impurities were determined in 7 batches of samples by principal component self-control with correction factor, the contents of impurity 3 were 0.01%-0.13%, the contents of impurity 4 were 0.10%-0.16%, the contents of impurity 5 were 0.02%-0.07%, the contents of impurity 6 were 0.04%-0.07%, the contents of polymer impurities were 0.03%-0.06%, the maximum single impurity contents were 0.01%-0.03%, while the total impurity contents were 0.28%-0.63%. Conclusion: Cefminox degradation solution in high temperature can be used to identify related impurities and polymer peaks as the systematic suitability testing solution. The RP-HPLC method was suitable for related substances as well as polymer impurities in cefminox sodium for injection. This work provides useful information for the quality control of cefminox sodium, which can contribute to establishment of reasonable impurity limits.

The components of biological samples are complex, and the concentration range of target analytes varies significantly. Therefore, sample pretreatment is particularly important for subsequent analysis. With the continuous development of analytical techniques, the requirements for sample pretreatment are also increasing. Pretreatment technologies are evolving towards microscale, time-saving, high-efficiency, online, and environmentally friendly directions to meet the requirements of complex matrices and trace analysis. Online pretreatment technologies integrate sample pretreatment steps and subsequent detection processes directly into an automated system, which can reduce steps and errors, improve analysis efficiency and sensitivity, and achieve automatic, rapid, and efficient analysis of target compounds. This paper reviews the online pretreatment technologies for biological samples in China and abroad in the past 10 years, offering valuable insights to guide future research and innovation in the realm of biological sample pretreatment.

Objective: To identify the related substances of progesterone sustained-release vaginal gel by liquid chromatography mass spectrometry (LC-MS). Methods: The separation was carried out on YMC-Triart C₁₈ (150 mm×4.6 mm, 3 μm) column by gradient elution using acetonitrile and water as the mobile phases. The accurate mass and elemental composition of the parent ions and their product ions of related substances were determined by electrospray-ionization quadrupole time-of-flight high resolution mass spectrometry (ESI Q TOF MS) at collision energies of 5-45 eV. The structures of the related substances were identified by spectral analysis. Results: Under the established analytical condition, progesterone and its related substances were adequately separated, and 18 major related substances were detected and identified by hyphenated techniques in progesterone sustained-release vaginal gel and their stressed samples. Among them, 7 were the impurities listed in the EP or previous reported, and the others were unknown related substances identified for the first time in this paper. The established LC-MS technique was effective for the separation and identification of the related substances of progesterone sustained-release vaginal gel. Conclusion: Progesterone is unstable under acid, alkaline, and high-temperature stress conditions, and prone to produce oxidation degradants. The research results can provide a reference for the quality control of progesterone sustained-release vaginal gel.

Objective: To identify the related substances in desloratadine using two-dimensional liquid chromatography-mass spectrometry (2D LC-MS) technology. Methods: A Waters Symmetry C₈ column (250 mm×4.6 mm, 5 μm) was employed. The mobile phase A consisted of a mixture containing 1% triethylamine and 10 mmol · L^-1 potassium dihydrogen phosphate solution adjusted to pH 2.0 with phosphoric acid, acetonitrile, and methanol (80∶10∶10), while mobile phase B contained 1% triethylamine, 10 mmol · L^-1 potassium dihydrogen phosphate solution (pH adjusted to 2.0 with phosphoric acid), acetonitrile, and tetrahydrofuran (30∶70∶5). A linear gradient elution was used for the first-dimension liquid chromatography separation of related substances in desloratadine. Individual separated components were captured through a multi-channel switching valve into retention vessels, then transferred to a Thermo BDS Hypersil C₁₈ column (100 mm×4.6 mm, 3 μm). After a second-dimension gradient elution with a mobile phase composed of 10 mmol · L^-1 ammonium acetate solution and methanol to achieve rapid desalting, electrospray ionization positive ionization-quadrupole-time-of-flight high-resolution mass spectrometry was employed to measure the accurate masses and elemental compositions of parent ions and their daughter ions of the related substances. Structural identification was achieved through spectral analysis. Results: Under the established analytical conditions, desloratadine and its related substances were well separated. A total of 12 related substances were detected and identified in desloratadine and its stressed degradation samples. Among these 12 degradants, three were known impurities, while the others are newly identified impurities. Conclusion: 2D LC-MS can effectively provide specific identification of desloratadine’s related substances under non-volatile mobile phase separation conditions. The findings from this study serve as a reference for controlling the quality of desloratadine.

Objective: To establish an HPLC method for simultaneous determination of vancomycin, caffeine and aminophylline in serum of children patients and apply it to clinical detection. Methods: 6% perchloric acid was used as protein precipitator and acetanilide was used as internal standard. The determination was performed on Nucifera C₁₈ column (250 mm×4.6 mm, 5 μm) with mobile phase methanol-0.05 mol · L^-1 potassium dihydrogen phosphate (18 ∶ 82, v/v). The detection wavelength was 236 nm, the flow rate was 1 mL · min^-1, the column temperature was 25 ℃, and the sample size was 20 μL. Results: The serum concentrations of vancomycin and aminophylline were in the range of 1.0-100 μg · mL^-1, and the standard curves were Y=0.010 6X+0.006 9 (r=0.998 8), Y=0.012 7X+0.008 4 (r=0.998 9), respectively. The serum concentration of caffeine had a good linear relationship in the range of 1.0-160 μg · mL^-1, and the standard curve was Y=0.015 4X-0.010 1 (r=0.999 1). Quantitative downlines were all 1.0 μg · mL^-1. The average recovery rates of the three compounds ranged from 97.8% to 103.1%, and the relative standard deviations of intraday and daytime precision were less than 10%, indicating good sample stability. Ten cases of children receiving vancomycin, aminophylline or caffeine were collected for method verification, which met the needs of clinical detection. Conclusion: The method is simple, rapid, accurate, and is suitable for the simultaneous determination of serum vancomycin, caffeine and aminophylline in children.

Objective: To optimize an LC-Q TOF MS method for the determination of target proteins expressed in recombinant cells from a cell bank. Methods: The recombinant Chinese hamster ovary (CHO) cell line expressing antibodies was selected. The supernatant of recombinant CHO cell suspensions was retained after 12 500 r · min^-1centrifuging for 10 min and treated with 50 mmol · L^-1 NH₄HCO₃ solution. Chymotrypsin was added for enzymatic digestion, and the comparative analyses were carried out using two LC-Q TOF MS with Advance Bio Peptide (100 mm×2.1 mm, 2.7 μm) column, the Sciex TRIPLE TOF 5600+ and the Agilent Q TOF G6545, respectively. To establish the database, the amino acid sequences of the characteristic peptides of the protein heavy and light chains were entered into SCIEX BioPharmaView Version 3.0 and Agilent MassHunter BioConfirm 12.0 software, respectively. The peptides detected in the samples were searched to identify the target peptides. Results: The samples were analysed by a Sciex TRIPLE TOF 5600+ instrument to obtain 8 characteristic peptides with 100% amino acid sequence coverage and the samples were analysed by an Agilent Q TOF G6545 instrument to obtain 12 characteristic peptides with 100% amino acid sequence coverage. Conclusion: The method established in this study is simple to operate, has high coverage and good stability, can be used to identify the expression of target proteins in recombinant CHO cell lines. It also provides a reference for the expression identification of target proteins in similar cell lines.

Objective: To establish an ultra-performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-QQQ MS/MS) method for the simultaneous determination of 14 active components in Qiyu Sanlong decoction, including L-argnine, monotropein, deacetyl asperulosidic acid, rutin, peimisine, calycosin-7-O-β-D-glucoside, caffeic acid, solasonine, solamargine, p-coumaric acid, ferulic acid, calycosin, astragaloside Ⅳ and astragaloside Ⅰ. Methods: The chromatographic separation experiment was performed on an ACQUITY UPLC BEH C₁₈ column(2.1 mm×100 mm, 1.7 μm), with gradient elution of 0.1% formic acid aqueous solution (A)-acetonitrile (B) as mobile phase at the flow rate of 0.2 mL · min^-1, injection volume of 5 μL, and column temperature of 35 ℃. The ion source was an electrospray ionization source (ESI), the scanning mode was simultaneous scanning of positive and negative ions, and the monitoring mode was multiple reaction monitoring. Results: The 14 active components revealed good linearity within their respective ranges (r>0.995 0), RSDs of precision and repeatability were below 2%, RSDs of stability were below 3%, and the average recoveries ranged from 88.4% to 108.5% with the RSDs ranging from 0.020% to 3.6%. The content ranges of the aforementioned 14 components in 10 batches of self-prepared Qiyu Sanlong decoction were as follows (in μg · g^-1): 667.28-785.78, 165.72-197.27, 196.32-275.60, 17.60-26.52, 4.68-10.75, 279.12-388.05, 26.00-47.57, 385.52-442.77, 288.00-358.82, 629.88-839.02, 86.67-125.83, 51.58-65.83, 25.50-37.53, and 55.50-76.13. Conclusion: The UPLC-QQQ MS/MS method established in this study is rapid, accurate, sensitive and repeatable, which can provide a reference for the quality control of Qiyu Sanglong decoction.

Objective: To establish a atomic absorption spectroscopy (AAS) method for detecting calcium content in recombinant human coagulation factor Ⅷ for injection, and evaluate its uncertainty. Methods: A calcium hollow cathode lamp light source was used. Air acetylene flame atomizer. Detection wavelength 422.7 nm. 8.9% lanthanum oxide solution was used as an ionization inhibitor. Conduct inspections on specificity, accuracy, precision, quantification limit, linearity and range, stability, etc. in accordance with the validation guidelines for drug quality standard analysis methods in Part 9101 of the 2020 edition of the Chinese Pharmacopoeia. The established method was applyed to detect the content of 6 batches of samples. Results: There was a good linear relationship between calcium element and absorbance in the concentration range of 0.0-5.0 μg · mL^-1, with r=0.999 8. The detection line was 0.071 6 μg · mL^-1; The quantification limit was 0.216 9 μg · mL^-1. The recovery rate of the spiked sample was 100.8% to 103. 2%. The repeatability RSD was 0.64%, and the solution was stable within 8 hours. The content determination results of 6 batches of samples all complied with the regulations. The uncertainty assessment result was (117.12±4.82) μg · mL^-1, k=2. Conclusion: AAS method is established for the detection of calcium content in recombinant human coagulation factor Ⅷ for injection.This method has the advantages of high sensitivity, fast analysis speed, good repeatability, high accuracy, and cost savings. At the same time, the uncertainty of this method is evaluated, which can provide quantitative evaluation indicators for the quality control of this variety.

Objective: To identify and analyze the chemical components of Bufei Jianpi formula by ultra-high performance liquid chromatography-coupled with high-resolution mass spectrometry (UPLC-HRMS). Methods: A Hypersil GOLD (2.1 mm×100 mm, 2.6 μm) column was used. Methanol (A)-0.1% formic acid water (B) was used as the mobile phase with gradient elution, the flow rate was 0.2 mL · min^-1, and the column temperature was 30 ℃.The mass spectrometry data were collected using the Full MS/dd-MS² scanning mode of positive and negative ions, and the characteristic fragment ion peak information was analyzed by compound discoverer. Combined with Chemspider, mzCloud and other databases and existing reports of relevant chemical composition information, the chemical components of Bufei Jianpi formula was analyzed by using the cracking prediction of Mass Frontier and its cracking rule. Results: A total of 221 compounds were identified from Bufei Jianpi formula, including 65 flavonoids, 40 phenylpropanoids, 21 terpenoids, 16 alkaloids and 79 other compounds. Conclusion: UPLC-Orbitrap Fusion Lumos Tribrid-MS can quickly identify the chemical components of Bufei Jianpi formula and qualitatively analyze the material basis of Bufei Jianpi formula, which can be used for the quality control of BufeiJianpi formula.

Objective: To establish an HPLC method for the simultaneous determination of chlorogenic acid, puerarin, 3’-methoxy puerarin, puerarin apioside, liquiritin, forsythoside A, 3,5-O-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, forsythin, honokiol and magnolol in Jinlian Quwen capsules. Methods: The analysis was performed on a Waters Atlantis^TM T3 (150 mm×4.6 mm, 3 μm) column, and the mobile phase was comprised of acetonitrile-0.1% phosphoric acid, with the flow rate of 1.0 mL · min^-1 in a gradient elution manner. The column temperature was set at 35 ℃. The injection volume was 4 μL and the UV detection wavelengths were set at 225 nm (detecting forsythin), 250 nm (detecting puerarin, 3’-methoxy puerarin and puerarin apioside), 276 nm(detecting liquiritin), 290 nm (detecting honokiol and magnolol) and 325 nm (detecting chlorogenic acid, 3,5-O-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid and forsythoside A). Results: All the 11 constituents showed good linearity within their detection ranges (r≥0.999 5), whose average recoveries (n=6) were 100.1%-108.1%, with the RSDs of 2.8%-4.1%. The content ranges of 11 components in three batches of samples were 7.505-7.606 mg · g^-1, 3.485-3.920 mg · g^-1, 0.969-1.068 mg · g^-1, 0.837-0.955 mg · g^-1, 1.009-1.436 mg · g^-1, 3.037-3.602 mg · g^-1, 5.259-5.371 mg · g^-1, 0.931-1.012 mg · g^-1, 1.428-2.053 mg · g^-1, 0.939-1.018 mg · g^-1 and 2.744-2.827 mg · g^-1, respectively. Conclusion: The method is simple, sensitive and reliable. It can be used as a reference for the establishment of quality standard of Jinlian Quwen capsules.

Objective: To confirm the validity of solvent/detergent (S/D) treatment and dry heating for inactivation of virus in C1 esterase inhibitor (C1-INH). Methods: The Sindbis virus in samples with S/D was inactivated by the S/D method, and the virus titer before and after inactivation was detected using the plaque assay. Dry heating method was used to inactivate encephalomyocarditis virus (EMCV) and porcine parvovirus (PPV), and cytopathic assay was used to detect the virus titer before and after inactivation. Results: After inactivation by the S/D method, the reductions of Sindbis virus in three batches of smaples with S/D were > 4.35 lgPFU · mL^-1, > 4.51 lgPFU · mL^-1, > 4.64 lgPFU · mL^-1, respectively. After dry heating, the reductions of EMCV in three batches of samples without S/D were ≥5.38 lgTCID₅₀/0.1 mL、≥5.12 lgTCID₅₀/0.1 mL、≥5.25 lgTCID₅₀/0.1 mL, respectively, and the reductions of PPV in three batches of samples without S/D were 4.57 lgTCID₅₀/0.1 mL、4.18 lgTCID₅₀/0.1 mL、4.68 lgTCID₅₀/0.1 mL, respectively. Conclusion: With evaluation on the inactivation capability of the indicator viruses, it is proved that the S/D treatment and dry heating has good inactivation and removal effect on the virus in C1-INH.

Objective: To establish a high-performance liquid chromatography for the determination of L-tartaric acid, benzenesulfonic acid, maleic acid, succinic acid, fumaric acid, citric acid, oxalic acid and L-malic acid in chemical reference standards. Methods: The Kromasil Eternity XT-5-C8 (250 mm×4.6 mm,5 μm)column or Waters Xbridge C18 (250 mm×4.6 mm,5 μm)column was used. The mobile phase consisted of 0.02 moL · L-1 KH2PO4(A)-methanol (B), with gradient elution at 0.5 mL · min-1. Detection wavelength was 210 nm, the column temperature was 20 ℃. Results: All eight organic acids showed good linearity within their respective ranges (r≥0.999 8). The method demonstrated good precision (RSD≤2%), stability (RSD≤2%) and repeatability (RSD≤2%). The average recovery rate (n=9) was 98%-102%. The method was applied to the determination of organic acid content in various chemical reference standards containing organic acids, and the measured values closely matched the theoretical values. Conclusion: The method is suitable for the determination of L-tartaric acid, benzenesulfonic acid, maleic acid, succinic acid, fumaric acid, citric acid, oxalic acid and L-malic acid in chemical reference products.

Objective: To develop the first national reference standards for the quantitative determination of bivalirudin, in order to effectively control the product quality of bivalirudin injections, and to explore alternative methods for the quantitative characterization of synthetic peptide reference materials. Methods: Infrared (IR) spectroscopy, UV spectroscopy, HPLC, MS were used to confirm the structure of bivalirudin. Related substance were analyzed by HPLC. The mass balance method was used to determine the content of bivalirudin, which was further verified by a peptide content assay corrected for related peptide impurities. In addition, the stability and uniformity of the candidate reference material were evaluated. Results: The content of the first batch of bivalirudin national reference standard was 88.8%, calculated on C₉₈H₁₃₈N₂₄O₃₃, and the stability and uniformity tests met the required specifications. Conclusion: Based on the structural characteristics of the synthetic peptides, multiple qualitative and quantitative methods were used to ensure the accuracy of the content assignment for the national reference standard of bivalirudin.

Objective: To establish a two reference substances for determination of multiple components (TRSDMC) method for the simultaneous determination of scutellarin, rosmarinic acid, negletein, carvacrol and thymol in Moslae Herba, which was more economical and effective for the quality control of Moslae Herba. Methods: The retention times of the five components in Moslae Herba were determined using HPLC on 13 different C₁₈ columns. The average retention time of each component under each column was then used as the standard retention time for that component. Rosmarinic acid (peak 2) and carvacrol (peak 4) were chosen as linear calibration standards. The chromatographic peaks were localized by using liner calibration with two reference substances (LCTRS). Rosmarinic acid was used as the control substance to determine the content of each component using a relative correction factor. And the results were compared with those obtained from the external standard method. Chemometric analysis was used to excavate the differential quality markers of Moslae Herba. Results: LCTRS had accurate prediction results for the measured components and enjoyed a wide range of column applications. The correction factors of scutellarin, negletein, carvacrol and thymol to rosmarinic acid were 0.853 3, 0.475 2, 3.034 7 and 2.738 6, respectively, and their relative standard deviations were below 2.0%. There was no significant difference between contents obtained by the two methods. The contents of scutellarin, rosmarinic acid, negletein, carvacrol and thymol in 21 batches of Moslae Herba were 0.05-2.87 mg · g^-1, 0.73-9.73 mg · g^-1, 0.04-0.99 mg · g^-1, 0.36-8.52 mg · g^-1 and 0.61-10.2 7 mg · g^-1, respectively. The 24 batches of samples could be clustered into three categories, and thymol, carvacrol and negletein ether could be used as differential quality markers. Conclusion: TSDMC method for the simultaneous determination of the contents of 5 components in Moslae Herba is stable and reliable, and provides a new idea for the overall quality control of Moslae Herba.

Objective: To establish a rapid analytical method for chemical components in complex traditional Chinese medicine (TCM) based on an integrated strategy combining ultra high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-Q TOF MS/MS) with feature-based molecular networking (FBMN), so as to systematically characterize the chemical components in Sishen pills. Methods: MS data for Sishen pills were acquired using UHPLC-Q TOF MS/MS, with separation performed on on a Waters HSS T3 column(2.1 mm×100 mm, 1.8 µm). The mobile phase was consisted of a gradient elution of 0.1% formic acid in water (A) and acetonitrile (B) at a flow rate of 0.3 mL · min^-1. The electrospray ionization (ESI) source was used for both positive and negative ion modes, with a scan range of m/z 80 to 1 500. The data were uploaded to the Global Natural Product Social Molecular Networking (GNPS) to create a FBMN for Sishen pills. Results: A total of 131 compounds were identified in Sishen pills, by analyzing retention time, accurate molecular mass, MS² fragmentation characteristics, comparison with reference standards and self-established database, as well as utilizing FBMN for predicting structural similarity of compounds. These compounds included 27 alkaloids, 63 flavonoids, 11 phenylpropanoids, 14 phenols, 8 terpenoids, and 8 other compounds. Conclusion: In this study, the chemical components of Sishen pills are quickly and comprehensively characterized, which layes a foundation for the effective materials and quality control research of Sishen pills. The study also provides insights for the rapid analysis of chemical constituents in other TCM formulas.

Adeno-associated virus (AAV), important vector in gene therapy, exhibits serotype diversity in its capsid proteins that significantly influence its tissue tropism, immune evasion capabilities, and gene transfer efficiency. Accurate serotype identification is important for ensuring the safety and efficacy of gene therapy products. This review aims to provide a comprehensive analysis of current methods used for the serotype identification of AAV capsid proteins, and to explore their application prospects in gene therapy. A systematic literature review has been conducted focusing on summarizing AAV capsid protein serotype identification techniques from various fields, including mass spectrometry, enzyme-linked immunosorbent assay, capillary electrophoresis, and differential scanning fluorimetry. With the future development of new technologies and improvements in existing ones, it is possible to identify AAV serotypes more quickly and accurately, thereby promoting the R&D of AAV based gene therapy products.

Objective: To compare the chemical composition changes in Kehuang before and after fermentation using multi-component content determination combined with chemometric analysis. Methods: HPLC was employed using a ZORBAX Eclipse Plus C₁₈ column (4.6 mm×250 mm, 5 μm). The mobile phase consisted of acetonitrile and 0.1% phosphoric acid aqueous solution, applied with gradient elution. The flow rate was set at 1.0 mL · min^-1,the column temperature was maintained at 30 ℃, the detection wavelength was 203 nm, and injection volume was 10 μL. This method was applied to analyze the chemical compositions of Kehuang before and after fermentation and to establish their corresponding chemical fingerprint profiles. Quantitative determination was conducted for 11 chemical constituents, including chlorogenic acid, cimifugin, notoginsenoside R₁, baicalin, berberine, quercetin, baicalein, wogonin, emodin, chrysophanol, and physcion. Furthermore, chemometric methods such as hierarchical cluster analysis (HCA), principal component analysis (PCA), and orthogonal partial least squares discriminant analysis (OPLS-DA) were employed to distinguish and compare the samples before and after fermentation, with the aim of identifying key differential compounds. Results: Chemical fingerprint profiles were established for Kehuang before and after fermentation, with 22 common peaks identified. The fingerprints had good specificity and can be used for quality evaluation of Kehuang. The results of multi-component content determination and chemometrics analysis revealed significant differences in the content of notoginsenoside R₁ (1.023-2.927 mg · g^-1), scutellarein (0.125-0.568 mg · g^-1), and berberine hydrochloride (2.151-3.068 mg · g^-1) among the crude Kehuang powder, fermented Kehuang powder, and the content of Kehuang capsules. Notoginsenoside R₁, scutellarein and berberine were identified as differential markers between pre- and post-fermentation of Kehuang, which could serve as quality indicators for distinguishing and identifying Kehuang before and after fermentation. Conclusion: The chemical composition of Kehuang changes significantly after fermentation, and the differential compounds have been clearly identified, which provides an analytical basis for quality control in the production of Kehuangcapsules.

The analysis of traditional Chinese medicine involves many fields, such as quality control of traditional Chinese medicine and basic research of traditional Chinese medicine substances, and is the basis of modernization research of traditional Chinese medicine. In recent years, derivatization technique, as one of the important methods in sample pretreatment, has been widely used in the analysis of traditional Chinese medicine, aiming to improve the stability, sensitivity, selectivity and separation of the components to be measured. This paper outlines the knowledge of sample derivatization technique, introduces its application in gas chromatography and high-phase liquid chromatography, and describes its application in different chemical compositions of traditional Chinese medicine with examples of traditional Chinese medicine analysis, so as to provide a reference for sample derivatization technique in the pre-treatment process of traditional Chinese medicine analysis.

Objective: To investigate the effect of adsorbed moisture on drug purity determination by differential scanning calorimetry (DSC). Methods: The DSC analysis for drug purity was performed with a heating rate of 0.5 ℃ · min^-1 under a nitrogen atmosphere (drying gas flow rate: 50 mL · min^-1). The optimized method reduced by 10 ℃ than the conventional method and included an additional heating segment at 1 ℃ · min^-1 for 10 min, while other parameters remained unchanged. Results: Without pre-drying, the conventional DSC method accurately determined the purity of imidazole, phenylephrine hydrochloride, and neostigmine methylsulfate samples with adsorbed moisture below 7%. After optimization, the method further eliminated moisture interference, allowing accurate analysis of samples with adsorbed moisture below 8%. Conclusion: Adsorbed moisture may affect DSC-based purity analysis. For general samples with a melting point above 80 ℃ and adsorbed moisture below 7%, pre-drying is unnecessary. The optimized method further reduces the impact of adsorbed moisture.

Objective: To clarify the differences between the “Room temperature” definitions in the European Pharmacopoeia and the Chinese Pharmacopoeia, to emphasize that storage temperature was closely related to the design of long-term stability studies and product labeling, and to investigate the effects of storage temperature variations on the critical quality attributes (CQAs) of terlipressin for injection, so as to raise awareness among generic drug manufacturers regarding this critical issue. Methods: Given the discrepancies in storage temperature recommendations across different manufacturers’ product inserts, the original drug’s long-term stability studies and storage conditions were traced. Validated methods for related substances and polymer content were employed to assess the impact of temperature differences on the product’s CQAs. Results: Samples stored at 30 ℃exhibited a significantly higher increase in related substances compared to those stored at 15 ℃. In one manufacturer’s product, polymer levels exceeded specification limits within just five months of storage at 30 ℃. The divergence among manufacturers stems from some companies misinterpreting the original drug’s labeling by directly translating without considering the differences between Chinese and European Pharmacopoeias. Conclusion: Storage temperature has a significant impact on the levels of related substances and polymer content in terlipressin for injection. To ensure product quality, the storage temperature in the labeling should be restricted to “not exceeding 25 ℃.”

Objective: To compare the effects of freshly cutting and traditional processing of Scutellariae Radix prepared slices, providing scientific basis for quality control of freshly cutting Scutellariae Radix prepared slices.Methods: ShimNex CS-C18(250 mm×4.6 mm, 5 μm) chromatographic column was used, the mobile phase was methanol (A) -0.2% phosphoric acid (B) with gradient elution at the flow rate of 1.0 mL · min-1, the column temperature was 30 ℃, the detection wavelength was 280 nm. The fingerprint of Scutellariae Radix prepared slices was established. Similarity evaluation, principal component analysis (PCA), and orthogonal partial least squares-discriminant analysis (OPLS-DA) were performed to screen out the differential components based on variable importance in projection (VIP) value>1, and the known differential components which was carried out on the screened known differential components were quantitatively analyzed. Results: Twenty common peaks of Scutellariae Radix prepared slices by freshly cutting and traditional processing were found from the fingerprints, and four of them were identified. The similarities of Scutellariae Radix prepared slices based on freshly cutting and traditional processing were 0.998-1.000 and 0.999-1.000, respectively. The similarities of Scutellariae Radix prepared slices based on freshly cutting to those based on traditional processing were 0.981-0.988. According to the principal component analysis, the cumulative variance contribution rate of the five principal components obtained from PCA was 78.512%, principal components 1-5 were the main factors affecting the quality of Scutellariae Radix prepared slices. OPLS-DA found differential nine components, and the order of significance of difference was peak 3>peak 5>peak 17(wogonin)>peak 15(baicalein)>peak 4>peak 12(wogonoside)>peak 7>peak 6(baicalin)>peak 9. The results of content determination showed that baicalein and wogonin were higher in freshly cutting prepared slices(P<0.01), whereas that of baicalin was lower in the traditional processing prepared slices (P<0.05). Conclusion: The processing technology of fresh cutting is feasible in the production of Scutellariae Radix prepared slices.

Objective: To develop a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method that can simultaneously determine co-administered trastuzumab and pertuzumab in human serum based on mimotope purification technique. Methods: Capture probes based on mimotope were used to capture trastuzumab and pertuzumab from serum samples, followed by reduction, alkylation, trypsin digestion, and quantification using LC-MS/MS. The sample was detected in positive mode. The UPLC separation was conducted using an Agilent SB C18 column (30 mm×2.1 mm, 2.7 μm) at 40 ℃. Mobile phase A was water (0.1% formic acid), and mobile phase B was acetonitrile (0.1% formic acid). The flow rate was set at 0.3 mL · min-1 alongside an injection volume of 10 μL.Gradient elution was used. The monitoring ion pairs of trastuzumab were m/z 485.5/234.0, m/z 485.5/335.5, m/z 485.5/608.3, and the monitoring ion pairs of pertuzumab were m/z 419.4/249.4, m/z 419.4/476.2, m/z 419.4/589.6. In this process, we examined the adsorption isotherms and adsorption kinetics of mimotope capture probe, the digestion efficiency of the surrogate peptide, and validated the developed method. Results: Capture probes based on mimotope had a high-affinity enrichment ability to trastuzumab and pertuzumab, and the incubation process could be finished in 1 h. The linearity ranges for trastuzumab and pertuzumab were 0.200-200 μg · mL-1, and the limits of quantitation were both 0.2 μg · mL-1. The intra-day and inter-day precisions (RSD) for trastuzumab and pertuzumab were within 11.3% and 12.3%, and the accuracies (bias) were within 12.1% and 11.5%. This new method was successfully used for detecting the concentration of 12 patients with co-administration mAbs, the detected serum concentration range of trastuzumab was 13.75-59.12 μg · mL-1, 37.55-127.20 μg · mL-1 for pertuzumab. Conclusion: The developed method based on mimotope purification technique overcomes the inherent drawbacks of protein A/G-based affinity separation purification, such as high cost, low stability, and possible activity loss. It is a promising technical approach for achieving personalized and precise clinical treatment, especially for mAbs administered in combination.

Objective: To elucidate the differences in the contents of pyrrolizidine alkaloids among different quality grades of Farfarae Flos. Methods: A UPLC-MS/MS method was established for simultaneous determination of three pyrrolizidine alkaloids, senecionine, senecionine N-oxide and senkirkine in Farfarae Flos of different quality grades.An ACQUITY UPLC HSS T3 column (150 mm×2.1 mm, 1.8 μm) was used, themobile phase was 0.5% formic acid water-methanol (80 ∶ 20) with isocratic elution. The MS system was operated by using electrospray ionization (ESI) in the positive ion mode, and the scan mode was in multiple reactions monitoring (MRM) mode. External standard method was used in the experiment. Results: The contents of senecionine in first-grade, second-grade, and ungraded Farfarae Flos were 0.06-0.16 μg · g-1, 0.20-0.49 μg · g-1 and 0.39-1.02 μg · g-1, respectively. The contents of senecionine N-oxide were 0.89-1.66 μg · g-1, 3.61-5.12 μg · g-1 and 4.47-7.87 μg · g-1, respectively. The contents of senkirkine were 46.53-85.00 μg · g-1, 122.95-227.43 μg · g-1 and 153.83-282.59 μg · g-1, respectively. In the flower buds, pedicels and roots of Farfarae Flos, the contents of senecionine were 0.07-0.18 μg · g-1,0.60-1.16 μg · g-1 and 0.22-1.65 μg · g-1, respectively. The contents of senecionine N-oxide were 0.64-1.59 μg · g-1,0.91-9.78 μg · g-1 and 1.58-5.89 μg · g-1, respectively. The contents of senkirkine were 51.35-82.22 μg · g-1, 176.29-246.80 μg · g-1and 321.00-343.30 μg · g-1, respectively. Conclusion: This study reveals the relationships between the content of pyrrolizidine alkaloids in Farfarae Flos and its quality grade and medicinal parts. These results provide new perspective for quality evaluation and standard improvement.

Objective: To develop an inductively coupled plasma mass spectrometry(ICP-MS) method for the determination of Cd, Pb, As, Hg, Co, V, Ni and Se in the crude drug of lanthanum carbonate. Methods: Samples were diluted with 3% nitric acid and directly injected. The matrix effect was eliminated by standard addition method and matrix matching method. Lanthanum oxide was added into the standard solution as the matrix. Compare the linearity, repeatability, accuracy, quantification limit, detection limit and sample determination results of the two methods by methodological validation and sample determination. Results: The linear ranges of ICP-MS standard addition method and matrix matching method were 0-30 ng · mL^-1, the correlation coefficients for all elemental impurities were good(r>0.998). Limits of detection were between 0.003 9-0.22 ng · mL^-1 and 0.009 1-0.72 ng · mL^-1. The RSD of repeatability(n=6) were between 1.5%-4.9% and 5.1%-6.9%. The recoveries were between 87.0%-98.3% and 83.4%-114.4%. The contents of 8 elemental impurities in the crude drug of lanthanum carbonate were basically same. Conclusion: The established two methods can effectively eliminate the matrix effect. They were both simple, rapid, sensitive, accurate and applicable for the elemental impurity control of lanthanum carbonate.

Objective: To establish a high-performance liquid chromatography (HPLC) method for the simultaneous determination of four components (lepenine, songorine, aconitine, and bullatine A) in Aconitum brachypodum Diels. Methods: The analysis was performed on an RX-C18 column (250 mm×4.6 mm, 5 μm) with a mobile phase composed of methanol and phosphate buffer solution (pH adjusted to 7.3 with 80% phosphoric acid) with a ratio of 62 ∶ 38. The detection wavelength was set at 210 nm. The column temperature was 35 ℃ and the flow rate was 1 mL · min-1. Results: Lepenine (0-1.30 μg, r=0.999 8), songorine (0-0.64 μg, r=0.999 9), aconitine (0-1.94 μg, r=0.999 6), and bullatine A (0-0.76 μg, r=0.999 7) all exhibited good linearity. The average recovery rates for the four components were 98.0%, 101.0%, 98.0%, and 103.0%, respectively. The contents of four components in 11 batches of Aconitum brachypodum Diels samples were 0.009%-0.261%(lepenine), 0.08%-0.46%(songorine), 0.1%-0.26%(aconitine), and 0.17%-0.55%(bullatine A). Conclusion: This method is simple, accurate, and reproducible, making it suitable for the simultaneous determination of the four alkaloids in Aconitum brachypodum Diels, which provides a valuable reference for the improved quality control of this herbal material.