Determination and Mechanism Prediction of Potential Active Ingredients in Erdongtang Based on UHPLC-QqQ-MS and Network Pharmacology / 中国实验方剂学杂志

ObjectiveTo establish an ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry（UHPLC-QqQ-MS） for determination of the active ingredients in Erdongtang， and to predict the targets and pathways of anti-insulin resistance action of this formula. MethodThe analysis was performed on an ACQUITY UPLC BEH C18 column（2.1 mm×100 mm， 1.7 μm） with the mobile phase of 0.1% formic acid aqueous solution（A）-acetonitrile（B） for gradient elution（0-3 min， 90%-87%A； 3-6 min， 87%-86%A； 6-9 min， 86%-83%A； 9-11 min， 83%-75%A； 11-18 min， 75%-70%A； 18-19 min， 70%-52%A； 19-22 min， 52%A； 22-25 min， 52%-5%A； 25-27 min， 5%-90%A； 27-30 min， 90%A）. The contents of active ingredients in Erdongtang was detected by electrospray ionization（ESI） and multiple reaction monitoring（MRM） mode under positive and negative ion modes. On this basis， network pharmacology was applied to predict the targets and pathways of Erdongtang exerting anti-insulin resistance effect. ResultThe 20 active ingredients in Erdongtang showed good linear relationships within a certain mass concentration range， and the precision， stability， repeatability and recovery rate were good. The results of determination showed that the ingredients with high content in 15 batches of samples were baicalein（1 259.39-1 635.78 mg·L-1）， baicalin（1 078.37-1 411.52 mg·L-1）， the ingredients with medium content were mangiferin（148.59-217.04 mg·L-1）， timosaponin BⅡ（245.10-604.89 mg·L-1）， quercetin-3-O-glucuronide（89.30-423.26 mg·L-1）， rutin（46.91-1 553.61 mg·L-1）， glycyrrhizic acid（55.97-391.47 mg·L-1）， neomangiferin（37.45-127.03 mg·L-1）， nuciferine（0.89-63.48 mg·L-1）， hyperoside（6.96-136.78 mg·L-1）， liquiritin（30.89-122.78 mg·L-1）， liquiritigenin（26.64-110.67 mg·L-1）， protodioscin（58.57-284.26 mg·L-1）， the ingredients with low content were wogonin（7.16-20.74 mg·L-1）， pseudoprotodioscin（5.49-22.96 mg·L-1）， ginsenoside Rb1（7.31-23.87 mg·L-1）， ginsenoside Rg1（10.78-28.33 mg·L-1）， ginsenoside Re（7.78-24.76 mg·L-1）， ophiopogonin D（2.08-4.29 mg·L-1）， methylophiopogonanone A（0.74-1.67 mg·L-1）. The results of network pharmacology indicated that the mechanism of anti-insulin resistance exerted by Erdongtang might be related to the phosphatidylinositol 3-kinase/protein kinase B（PI3K/Akt） signaling pathway. ConclusionThe established UHPLC-QqQ-MS has the advantages of simple sample processing， strong exclusivity and high sensitivity， and can simultaneously determine the contents of the main ingredients from seven herbs in Erdongtang， which can lay the foundation for the development of Erdongtang compound preparations. The results of the network pharmacology can provide a reference for the mechanism study of Erdongtang in the treatment of type 2 diabetes mellitus.

Using Liquid Chromatography-Tandem Mass Spectrometry in Detecting Plasma Lyso-GL3 Levels in Patients with Fabry Disease and the Association Analysis of Phenotype-Genotype of the Disease / 罕见病研究

ObjectiveUsing the liquid chromatography-tandem mass spectrometry (LC-MS/MS) to determine the plasma level of Lyso-GL3 in patients with Fabry disease and to analyze the clinical application of the method.MethodsThirty-nine patients with a genetic diagnosis of Fabry disease were included, and plasma levels of Lyso-GL3 were measured by LC-MS/MS analysis, and detailed clinical information of the patients was obtained including: α-galactosidase A activity, genetic variants, quantification of urine protein, mean arterial pressure, and estimation of glomerular filtration rate, and the differences in the levels of Lyso-GL3 in different clinical phenotypes and genotypes were statistically analyzed, as well as the association with clinical indicators.ResultsLyso-GL3 showed good linearity within 0.7856-400 ng/mL(r=0.9992).Further analysis of 39 Fabry disease patients diagnosed in Ruijin Hospital, Shanghai Jiao Tong University School of Medicine showed a median Lyso-GL3 concentration of 23.6 ng/mL(4.3-92.9 ng/mL); Lyso-GL3 levels were significantly higher in patients with both the frameshift and the splicing mutations, as well as in patients with the nonsense mutations, than in patients with the missense mutations (median value 119.7 ng/mL vs. 11.9 ng/mL, P=0.006, and median value 97.0 ng/mL vs. 11.9 ng/mL, P=0.015, respectively). Whereas, association analysis revealed that Lyso-GL3 was not significantly associated with urinary protein, mean arterial pressure and estimated glomerular filtration rate.ConclusionsThe using of LC-MS/MS to quantify plasma Lyso-GL showed significant differences in Lyso-GL3 concentrations between classical and atypical phenotypes, suggesting that plasma Lyso-GL3 may help with clinical phenotypes. However, Lyso-GL3 levels is found to be overlapped between genotypes. No significant linear correlation was found between Lyso-GL3 and renal clinical indicators, suggesting the urgent need in finding a more accurate tool to assess renal involvement and prognosis in patients with Fabry disease.

The trend of changes in serum vitamin A, D, and E levels during pregnancy / 中华检验医学杂志

Objective:High performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to quantify the levels of vitamins A, D and E in pregnant women during the second trimester, and to investigate the change trends of serum vitamins A, D and E levels during pregnancy.Method:A total of 720 pregnant women with an average age of (29.7±4.4) years and 12-22 weeks of gestation were included from October 1, 2021 to October 30, 2022 in the obstetrics department of the People′s Hospital of Wuhan University. The concentrations of vitamins A, D and E were determined by HPLC-MS/MS. The concentration levels of each group were statistically analyzed and the deficiency rate were calculated.Results:The distribution range of vitamin A, D and E (95% CI) was 0.74-2.74 μmol/L, 2.88-25.37 ng/ml and 6.18-35.08 μmol/L, with the deficiency rates were 9.30%, 93.76% and 35.83%, respectively. Vitamin A, D and E levels in the twin group were (1.67±0.51) μmol/L, (13.18±7.44) ng/ml and 11.97 (8.85, 14.60) μmol/L, respectively. They were significantly higher than those in the singlet group (1.45±0.36) μmol/L, (10.87±5.26) ng/ml and 10.46 (6.99, 14.11) μmol/L, with statistical significance by independent sample t-test ( P<0.001). The concentration of vitamin D in the lower BMI group (<22 kg/m 2) was (12.54±5.74) ng/ml, significantly higher than that in the fat group (≥22 kg/m 2) (10.46±4.90) ng/ml, and the rank-sum test was statistically significant ( P<0.001). Conclusion:In this study, the levels of three vitamins were monitored in mid-pregnancy using HPLC-MS/MS, and the changes of serum vitamin A, D, and E levels during pregnancy were analyzed.

Development of a LC-MS/MS method for the determination of vancomycin in human serum and validation of its clinical value / 中华检验医学杂志

Objective:The aim of our study is to develop an LC-MS/MS method using isotope internal standard for the determination of vancomycin in human blood serum and to validate its clinical value.Method:We conducted a methodological evaluation study using serum samples from 221 hospitalized patients (142 males and 79 females; mean age (59.31±15.32) years) who received treatments of vancomycin at the Sir Run Run Shaw Hospital of Zhejiang University between March 2021 and June 2022. In addition, thirty clinical residual serum samples from healthy individuals (15 males and 15 females; mean age (35.65±9.86) years) undergoing physical examination were used for methodological evaluation. The method was established using AB Sciex Triple Quad 4500 MD liquid chromatography-tandem mass spectrometer and chromatographic separation was carried out using a Phenyl-Hexyl column with gradient elution. The mobile phase was composed of 0.1% formic acid in water and methanol; the column temperature was 40℃; Vancomycin-[d12] TFA salt was used as the internal standard (IS). The sensitivity, specificity, linearity, accuracy, imprecision, matrix effect, and carry-over of the method were evaluated.Results:The detection limit of vancomycin was 0.2 mg/L and the lowest limit of quantification was 0.5 mg/L. It showed good linearity ( R2=0.998 4) in the 1 to 50 mg/L concentration range. Accuracy (recovery rate 87.45%-112.69%), intra-day and inter-day imprecision ( CV 4.91%-7.69%), internal standard standardized matrix factor (90.22%-104.29%). Carryover pollution was negligible. Of the 221 patients, the mean trough concentrations of vancomycin in serum was (13.15±8.56) mg/L. Conclusion:The LC-MS/MS method for the detection of serum vancomycin established in our laboratory meets the requirements of the reference method, and can be used for the monitoring of clinical therapeutic drugs.

Analysis of Forty-Two Psychoactive Substances in a Single Hair by Micro-Segmental Technique / 法医学杂志

OBJECTIVES@#To establish an LC-MS/MS method based on single hair micro-segmental technique, and verify the detection of 42 psychoactive substances in 0.4 mm hair segments.@*METHODS@#Each piece of single hair was cut into 0.4 mm segments and extracted by sonication and the segments were immersed in dithiothreitol-containing extraction medium. Mobile phase A was the aqueous solution containing 20 mmol/L ammonium acetate, 0.1% formic acid, and 5% acetonitrile. Mobile phase B was acetonitrile. An electrospray ionization source in positive ion mode was used for data acquisition in multiple reaction monitoring (MRM) mode.@*RESULTS@#The 42 psychoactive substances in hair had a good linear relationship within their respective linear ranges (r>0.99), the limits of detection were 0.2-10 pg/mm, the limits of quantification were 0.5-20 pg/mm, the intra-day and inter-day precisions were 1.5%-12.7%, the intra-day and inter-day accuracies were 86.5%-109.2%, the recovery rates were 68.1%-98.2%, and the matrix effects were 71.3%-111.7%. The method was applied to hair samples collected from one volunteer at 28 d after a single dose of zolpidem, with zolpidem detected in 5 hairs was 1.08-1.60 cm near the root tip, and the concentration range was 0.62-20.5 pg/mm.@*CONCLUSIONS@#The micro-segmental technique of single hair analysis can be applied to the investigation of drug-facilitated sexual assault cases.

Determination of tetrodotoxin in salted pufferfish by liquid chromatography-tandem mass spectrometry / 预防医学

Objective@#To develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with cation exchange-based solid phase extraction (SPE) for determination of tetrodotoxin (TTX) in salted pufferfish. @*Methods@#Evenly crushed salted pufferfish samples were subjected to ultrasound-assisted extraction with 0.5% acetic acid/50% methanol/water. The extract was cleaned with cation exchange-based SPE cartridge and eluted with 0.3% hydrochloric acid and 50% acetonitrile/water. The eluent was neutralized with ammonia and separated with a Waters XBridgeTM BEH Amide column (150 mm×3.0 mm, 1.7 μm), and determined using LC-MS/MS in a multiple reaction monitoring mode.@*Results@#The matrix effects of TTX were 85.7%-92.4%, and the matrix suppression effect was under effective control following clean-up procedures using the optimized SPE method. The TTX showed a good linear relationship at the range of 2.0 to 4 000 μg/kg, with a correlation coefficient (r2) of 0.999 2. The limits of detection and quantitation for TTX in sample matrix were 1.0 μg/kg and 2.0 μg/kg, respectively. The mean spiked-recovery rates were 81.2% to 96.5% at spiked amounts of 2.0, 200 μg/kg and 2 200 μg/kg, with relative standard deviations (RSDs) of 4.3% to 7.5%. The intraday accuracy and precision of TTX were 84.4% to 95.6% and 4.9% to 5.8% in quality control samples, and the interday accuracy and precision of TTX were 86.1% to 94.9% and 5.5% to 8.5% in quality control samples. The detection of TTX was 60.5% in 38 market-sold salted pufferfish products using the established LC-MS/MS method.@*Conclusion@#The established LC-MS/MS method is effective for accurate quantitative determination of TTX in salted pufferfish.

Rapid screening of 28 alkaloids in food poisoning samples by liquid chromatography-tandem mass spectrometry / 中国热带医学

@#Abstract: Objective　To investigate a poisoning incident caused by eating eight treasure congee, and establish liquid chromatography (LC)-mass spectrometry (MS)/MS screening method of 28 alkaloids to provide references for disposal of similar poisoning incidents. Methods　LC-MS/MS was used for screening 28 alkaloids in the urine, eight treasure congee and food raw material, and the detected alkaloids were quantified. Samples were extracted with 0.4% formic acid aqueous solution and separated by a Acquity UPLC BEH C18 column (1.7 μm, 100 × 2.1 mm). Acetonitrile-0.2% formic acid aqueous solution was used as the mobile phase and gradient elution was adopted. The ionization mode was electrospray positive ionization mode, and the detection method was multi-reaction monitoring (MRM). Analytes were quantified with the external standard method. Results　In the concentration range of 0-100 ng/mL, the linear correlation coefficient r were greater than 0.999 for 28 alkaloids. The recovery of 28 alkaloids in urine sample ranged from 63.0% to 105.0%, and the relative standard deviations (RSDs) were between 5.8% and 8.6%. The recovery of 28 alkaloids in eight treasure congee sample ranged from 72.0% to 109.0%, and the RSDs were between 6.3% and 9.7%. The recovery of 28 alkaloids in semen sesami nigrum sample ranged from 60.0% to 95.0%, and the RSDs were between 4.8% and 8.2%. Hyoscyamine (2 380.0 ng/mL), scopliamine (3.6 ng/mL) and rac-anisodamine (4.7 ng/mL) were detected in the patient's urine. Hyoscyamine (63.3 μg/g), scopliamine (5.7 μg/g) and rac-anisodamine (2.1 μg/g) were detected in eight treasure congee. Hyoscyamine (901.0 μg/g), scopliamine (80.0 μg/g) and rac-anisodamine (30.1 μg/g) were detected in the seed of Datura stramonium L. The ratio of scopliamine and hyoscyamine in the seed of D. stramonium was 1∶11, which complies with the characteristics of D. stramonium L. In urine sample, the proportion of scopliamine and rac-anisodamine was 0.15% and 0.20%, and hyoscyamine accounted for 99.65%. Conclusion　Seed morphology, the content range and proportion of three alkaloids are all in accord with the characteristics of D. stramonium. Combined with the clinical symptoms of atropine poisoning, it can be deduced that this incident is a family food poisoning caused by accidental consumption of seed of D. stramonium L. The method can provide technical support for the clinical diagnosis and treatment of alkaloid poisoning patients, and also provide a basis for emergency detection and disposal of alkaloid poisoning events.

The PK bioanalysis method study of c-Met antibody-drug conjugate (RC108) in cynomolgus monkey / 药学学报

Antibody-drug conjugate (ADC) has the characteristics of low toxicity and high efficiency, and plays an important role in cancer treatment. However, due to the complexity of its structure, it brings difficulties in pharmacokinetic (PK) bioanalysis. This study established an analytical method for the detection of ADC (RC108) in cynomolgus monkey plasma by ligand-binding assay (LBA) and liquid chromatography tandem mass spectrometry (LC-MS/MS), which was used to analyze and quantify the total antibody, bound antibody and free drug in cynomolgus monkey plasma. Based on the LBA method, rabbit anti-RC108 Fab and mouse anti-MMAE (monomethyl auristatin E) mAb were pre-coated in 96-well plates as the total antibody and antibody binding reagents, respectively. The samples to be tested were added, and then the detection reagents were added in turn. Goat anti-human IgG (H+L)-HRP, chromogenic solution tetramethylbenzidine (TMB), H2SO4 terminate the reaction, read data at 450 nm/630 nm wavelength of microplate reader; LC-MS/MS analysis method quantifies MMAE concentration, and refer to relevant regulations for methodological validation. The analytical method for quantifying total antibody, bound antibody and free drug of RC108 drug obtained good accuracy and precision, and the selectivity, dilution linearity, hook effect, parallelism and stability were verified. Meet the requirements of biological analysis. Finally, a bioanalytical method for the determination of the concentration of the test substance RC108 (total antibody, conjugated antibody, free MMAE) in cynomolgus monkey plasma with high sensitivity and high throughput was established by LBA and LC-MS/MS method. Subsequent non-clinical research on PK research in cynomolgus monkeys will provide technical support.

Simultaneously quantitative analysis of 35 components in gualoupi injection using hydrophilic interaction liquid chromatography tandem mass spectrometry / 药学学报

A hydrophilic interaction chromatography tandem mass spectrometry method was developed for simultaneous quantification of 35 components in gualoupi injection. The analytes were separated with an ACQUITY XBridge Amide column using 20 mmol·L-1 ammonium formate aqueous solution (pH 3.0) as mobile phase A and 20 mmol·L-1 ammonium formate (pH 3.0)∶acetonitrile (1∶9) as mobile phase B for gradient elution. Mass spectrometry with dynamic multiple reaction monitoring and external standard method were used for quantitative analysis. A total of 35 components were determined in 10 batches of gualoupi injection. The results showed that the 35 compounds had a good linear relationship within their respective concentration ranges with the correlation coefficients (R2 > 0.998 0), the recoveries ranged from 76.6% to 118.5%. The results showed that γ-aminobutyric acid, trigonelline, alanine, threonine, homoserine, citrulline, and leucine were abundant in gualoupi injection, while nicotinamide, methylsuccinic acid, cytosine and choline account for a low percentege. The present study provides an important reference for elucidation of the effective material basis and the improvement of quality standard of gualoupi injection.

Content determination of 3 alkaloids in different origins of Tibetan Corydalis pallida by UPLC-MS/MS / 中国药房

OBJECTIVE To establish and apply a method for simultaneous determination of the contents of dicentrine， protopine and coptisine in Tibetan Corydalis pallida of different origins， and to provide reference for origin determination and quality control of the kind of medicinal materials. METHODS Ultra performance liquid chromatography-tandem quadrupole mass spectrometry method was used. The determination was performed on Agilent EC-C18 column （100 mm×2.1 mm， 2.7 μm） with mobile phase consisted of acetonitrile-0.1% formic acid by gradient elution. The flow rate was 0.2 mL/min， and the column temperature was set at 35 ℃ . MS detection was carried out by electrospray ionization in positive modes， multiple reaction monitoring mode was used for quantitative analysis. RESULTS The injection mass concentrations of dicentrine， protopine， coptisine ranged from 5.88 to 117.60， 53.70 to 1 074.00， and 4.85 to 97.00 ng/mL， respectively， showing a good linear relationship with their respective peak areas （r＝0.998 2， 0.991 9， and 0.999 6， respectively）. The limits of quantitation were 2.35， 1.07 and 1.46 ng/mL； the limits of detection were 1.17， 0.54， 0.49 ng/mL， respectively. RSDs of precision， stability （24 h） and repeatability tests were all lower than 2.0％. The average recovery rates were 97.41%， 98.89% and 105.44%（ all RSDs＜5.0％， n＝6）. CONCLUSIONS The established method has good selectivity and high accuracy， and is suitable for the rapid analysis of dicentrine， protopine and coptisine in Corydalis. The total contents of three alkaloids in different original medicinal materials are from high to low in order of C. chrysosphaera， C. mucronifera， C. pygmaea， C. hendersonii and C. conspersa. The alkaloid contents in C. chrysosphaera and C. mucronifera are relatively similar， but no dicentrine has been detected in C. conspersa and C. hendersonii.

Determination of 10 organophosphorus flame retardants in drinking water by On-line SPE-UPLC-MS/MS / 公共卫生与预防医学

Objective To establish a method for the determination of 10 organophosphorus flame retardants in drinking water by on-line solid phase extraction coupled with high performance liquid chromatography-tandem mass spectrometry (On-line SPE-UPLC-MS/MS). Methods After adding the internal standard, the water sample was filtered by Millipore filtration, and then concentrated and detected by Online SPE-UPLC-MS/MS. Samples were concentrated by C8 SPE column and separated by C18 column with acetonitrile-water-formic acid as the mobile phases gradient elution，and were detected by multiple reaction monitoring (MRM) acquisition under anion mode. Results The 10 organophosphorus flame retardants all displayed good linear relationships within a certain range of concentrations, with the correlation coefficients being more than 0.990. The method detection limits were 0.60-5.50 ng/L, and the spiked recoveries of low, medium and high concentrations were 64%-106% , 83%-104% and 85%-99%, respectively. Conclusion The method is simple, sensitive, rapid, accurate and reliable, so it is applicable for the determination of 10 organophosphorus flame retardants in drinking water.

Comparison of Effect of Ancient and Modern Processing Methods on Chemical Components of Lilii Bulbus Decoction Based on UHPLC-Q-Orbitrap HRMS / 中国实验方剂学杂志

ObjectiveTo compare the effects of different processing methods in ancient and modern times on the chemical components of Lilii Bulbus decoction， and to provide experimental support for the origin processing， decoction piece processing and clinical application of this herb. MethodUltra high performance liquid chromatography tandem quadrupole electrostatic field orbitrap high resolution mass spectrometry（UHPLC-Q-Orbitrap HRMS） was used for structural identification of the compounds using excimer ions， secondary MS and characteristic fragment ions， and referring to relevant literature and database information. Principal component analysis（PCA） and orthogonal partial least squares discriminant analysis（OPLS-DA） were used to screen the main differential components， the differential components were quantitatively studied by high performance liquid chromatography（HPLC）， in order to compare the types and contents of chemical components in the decoction of different processing products of Lilii Bulbus. ResultA total of 24 chemical components were identified from the decoction of different processed products of Lilii Bulbus， water extract and scalding liquid of fresh Lilii Bulbus， including 17 phenols， 5 saponins and 2 alkaloids. Compared with the fresh Lilii Bulbus decoction， the contents of regaloside A， p-coumaric acid， colchicine and other components in the decoction of dry Lilii Bulbus processed by scalding method decreased， the content of regaloside C in the decoction of dry Lilii Bulbus processed by steaming method decreased， and the contents of regaloside A and regaloside C in the decoction of fresh Lilii Bulbus processed by water immersion also decreased. Compared with the decoction of dry Lilii Bulbus processed by scalding method， the overall content of components in the fresh Lilii Bulbus decoction and the decoction of fresh Lilii Bulbus processed by water immersion was higher， the contents of components in the decoction of dry Lilii Bulbus processed by steaming method was higher， except for the slightly lower content of regaloside C. ConclusionDifferent processing processes have a certain effect on the types and contents of chemical components in Lilii Bulbus decoction. Scalding process is beneficial to the preservation of Lilii Bulbus， but can cause the loss of effective components. Compared with scalding method， steaming method can prevent browning of Lilii Bulbus and reduce the loss of its active ingredients. The processing method of removing foam after overnight immersion proposed by ZHANG Zhongjing may be more conducive to the treatment of Baihe disease， which can provide reference for the clinical rational application and mechanism research of different processed products of Lilii Bulbus.

Rapid determination of four herbicides in urine with ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry / 预防医学

Objective@#To establish a ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry method for rapid simultaneous determination of quinclorac, acetochlor, butachlor and metolachlor in urine.@*Methods@#Urine samples were diluted 10 times, prepared into the mixed standard solution, and subjected to gradient elution on the ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 μm) with 0.1% formic acid and acetonitrile as the mobile phase. The quinclorac, acetochlor, metolachlor and butachlor levels were determined using electrospray ionization-positive ultra-high performance liquid chromatography-tandem triple quadrupole mass spectrometry with the multiple reaction monitoring mode.@*Results@#Four herbicides were effectively separated on the ACQUITY UPLC BEH C18 column (100 mm× 2.1 mm, 1.7 μm), and good linear relationships were observed for quinclorac, acetochlor and butachlor at 1 to 25 μg/L and for metolachlor at 0.2 to 25 μg/L, with all linear correlation coefficients of >0.999. The detection limts of quinclorac, acetochlor, butachlor and metolachlor were 0.10, 0.10, 0.20 and 0.01 μg/L, respectively. The recovery rates of quinclorac, acetochlor and butachlor were 107.42%, 93.94% and 90.27% from urine samples at a spiked level of 5 µg/L, with relative standard deviations of 4.82%, 3.84% and 6.76%, and the recovery rate of metolachlor was 89.51% at a spiked level of 0.5 µg/L, with a relative standard deviation of 8.98%.@*Conclusion@#The chromatography and mass spectrometry conditions are optimized in this ultra-high performance liquid chromatography-tandem mass spectrometry, which is effective for rapid simultaneous determination of quinclorac, acetochlor, metolachlor and butachlor in urine samples.

Analysis of Suitable Processing Time of Rehmanniae Radix Praeparata Processed with Amomi Fructus and Citri Reticulatae Pericarpium Based on UPLC-Q-TOF-MS / 中国实验方剂学杂志

ObjectiveTo investigate the relative content changes of differential metabolites and reducing sugars during the processing process of Rehmanniae Radix Praeparata （RRP） processed with Amomi Fructus （AF） and Citri Reticulatae Pericarpium （CRP）， and to lay the foundation for revealing the processing principle of this characteristic variety. MethodThe samples of the 0-54 h processing process of RRP processed with AF and CRP were taken as the research object， and their secondary metabolites were detected by ultra performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry （UPLC-Q-TOF-MS）. The 0.1% formic acid aqueous solution （A）-acetonitrile （B） was used as the mobile phase for gradient elution （0-1 min， 1%-3%B； 1-10 min， 3%-9%B； 10-15 min， 9%-12%B； 15-22 min， 12%-18%B； 22-31 min， 18%-24%B； 31-35 min， 24%-100%B； 35-36 min， 100%-5%B； 36-40 min， 5%-1%B； 40-45 min， 1%B）， column temperature was 40 ℃， injection volume was 3 μL， flow rate was 0.3 mL·min-1. Electrospray ionization （ESI） was used to scan and collect MS data in the negative ion mode， the scanning range was m/z 50-1 250. Data analysis was carried out using PeakView 1.2 software， and the chemical composition of RRP processed with AF and CRP was identified by combining the literature information and chemical composition databases. The MS data were normalized by MarkerView 1.2， and then the multivariate statistical analysis was applied to screen the differential metabolites， and the changes of the relative contents of the differential metabolites with different processing times was analyzed， finally， correlation analysis was performed between the differential metabolites， the change of the reducing sugar content was combined to determine the most suitable processing time of RRP processed with AF and CRP. ResultA total of 121 compounds were identified from RRP processed with AF and CRP at different processing times， and 12 differential metabolites were screened out by multivariate statistical analysis， including catalpol， hesperidin， isoacteoside， acteoside， narirutin， echinacoside， isomartynoside， decaffeoylacteoside， 6-O-E-feruloylajugol， dihydroxy-7-O-neohesperidin， jionoside D， and rehmapicroside. With the prolongation of processing time， the relative contents of these 12 differential metabolites and reducing sugars changed slightly at 52-54 h. ConclusionUPLC-Q-TOF-MS can comprehensively and accurately identify the chemical constituents of RRP processed with AF and CRP at different processing times， and the suitable processing time of 52-54 h is determined according to the content changes of different metabolites and reducing sugars， which provides a basis for revealing the scientific connotation of the processing principle of this variety.

Simultaneous determination of 15 bile acids in Tongren niuhuang qingxin pills by UPLC-MS/MS / 中国药房

OBJECTIVE To establish a method for simultaneous determination of 15 bile acids in Tongren niuhuang qingxin pills， and to determine the contents of 15 batches of samples. METHODS Using dehydrocholic acid as internal standard， the determination was performed by ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） method. The determination was performed on Hypersil GOLD C18 column with methanol-0.1% formic acid solution as the mobile phase by gradient elution at the flow rate of 0.2 mL/min. The column temperature was 40 ℃ ， and the sample size was 2 µL. Using heated electrospray ion source， parallel reaction monitoring mode scanning was performed in negative ion mode. SPSS 24.0 software was used for chemical pattern recognition analysis of content determination results. RESULTS The 15 bile acid components had a good linear relationship with peak area （all R2≥0.998 9）； their precision， repeatability and stability were all good （all RSD≤5.49%）； the average recoveries were 93.8%-105.7% （RSD was 0.5%-5.8%）. The average contents of taurocholic acid， 7-oxodeoxycholic acid， 12-dehydrocholic acid， glycocholic acid， 3-oxo-7α， 12α-hydroxy-5β-cholanoic acid， taurochenodeoxycholic acid， 3α-hydroxy- 7-oxo-5β -cholanic acid， hyocholic acid， taurodeoxycholic acid sodium salt hydrate， hyodeoxycholic acid， cholic acid， glycochenodeoxycholic acid， glycodeoxycholic acid， chenodeoxycholic acid and deoxycholic acid were 670.56， 25.97， 10.54， 280.12， 4.04， 29.81， 182.98， 813.55， 120.95， 220.31， 797.37， 18.37， 68.59， 30.13， 59.82 μg/g， respectively. Both cluster analysis and principal component analysis divided 15 batches of Tongren niuhuang qingxin pills into 2 categories， S1-S12 as one category and S13-S15 as the other category. CONCLUSIONS The established method is accurate， sensitive and specific， and can determine many types of bile acids. It also can quickly achieve the quantitative analysis of 15 bile acids in Tongren niuhuang qingxin pills， which is suitable for the quality control of this drug.

Determination of 22 phospholipids in serum by ultra performance liquid chromatography-tandem mass spectrometry / 中华劳动卫生职业病杂志

Objective: To establish ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the determination of 22 phospholipids in serum. Methods: In September 2022, Using synthetic non endogenous phospholipids as internal standard, phospholipids in serum were extracted by methanol-dichloromethane (2∶1, V/V) protein precipitation method. Chromatographic separation was achieved on an ACQUITY UPLC BEH shield RP18 column, and the mobile phase was methanol/water (5∶95, V/V) containing 10 mM ammonium formate and methanol. Detection was performed in multiple reaction monitoring mode with ion mode switching. And the method was applied by analyzing phospholipids in the serum of coal workers' pneumoconiosis patients. Results: The 22 phospholipids showed good linear relationships in their respective concentration ranges and the correlation coefficients were higher than 0.990. The spiked recoveries of the 22 phospholipids were 81.03%-121.63% at the three spiked levels. The intra-assay were less than 14.52%, and the inter-assay were less than 15.00%. Conclusion: The method with the advantages of simplicity, stability and high sensitivity, and it can be used for the analysis of phospholipids in serum.

Determination of 10 mycotoxins in Hippophae Fructus medicinal and edible products by ultra-performance liquid chromatography- tandem mass spectrometry / 中国中药杂志

An analytical method for 10 mycotoxins in Hippophae Fructus medicinal and edible products was established in this study, and the contamination of their mycotoxins was analyzed. First of all, the mixed reference solution of ten mycotoxins such as aflatoxin, ochratoxin, zearalenone, and dexoynivalenol was selected as the control, and the Hippophae Fructus medicinal and edible products were prepared. Secondly, based on the ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) technology, 10 mycotoxins in Hippophae Fructus medicinal and edible products were quantitatively investigated and their content was determined. Finally, the contamination of mycotoxins was analyzed and evaluated. The optimal analysis conditions were determined, and the methodological inspection results showed that the 10 mycotoxins established a good linear relationship(r>0.99). The method had good repeatability, test sample specificity, stability, and instrument precision. The average recovery rates of 10 mycotoxins in Hippophae Fructus medicinal products, edible solids, and edible liquids were 90.31%-109.4%, 87.86%-107.8%, and 85.61%-109.1%, respectively. Relative standard deviation(RSD) values were 0.22%-10%, 0.75%-13%, and 0.84%-8.5%, repsectively. Based on UPLC-MS/MS technology, the simultaneous determination method for the limits of 10 mycotoxins established in this study has fast detection speed, less matrix interference, high sensitivity, and accurate results, which is suitable for the limit examination of 10 mycoto-xins in Hippophae Fructus medicinal and edible products.

Formation and characteristics of polystyrene nanoplastic-plant protein corona / 生物工程学报

To investigate the formation of polystyrene nanoplastic-plant protein corona and its potential impact on plants, three differently modified polystyrene nanoplastics with an average particle size of 200 nm were taken to interact with the leaf proteins of Impatiens hawkeri for 2 h, 4 h, 8 h, 16 h, 24 h, and 36 h, respectively. The morphological changes were observed by scanning electron microscopy (SEM), the surface roughness was determined by atomic force microscopy (AFM), the hydrated particle size and zeta potential were determined by nanoparticle size and zeta potential analyzer, and the protein composition of the protein corona was identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The proteins were classified in terms of biological processes, cellular components, and molecular functions to study the adsorption selection of nanoplastics to proteins, investigate the formation and characteristics of polystyrene nanoplastic-plant protein corona and predict the potential impact of protein corona on plants. The results showed that the morphological changes of the nanoplastics became clearer as the reaction time extends, as evidenced by the increase in size and roughness and the enhancement of stability, thus demonstrating the formation of protein corona. In addition, the transformation rate from soft to hard protein corona was basically the same for the three polystyrene nanoplastics in the formation of protein corona with leaf proteins under the same protein concentration conditions. Moreover, in the reaction with leaf proteins, the selective adsorption of the three nanoplastics to proteins with different isoelectric points and molecular weights differed, and the particle size and stability of the final formed protein corona also differed. Since a large portion of the protein fraction in protein corona is involved in photosynthesis, it is hypothesized that the formation of the protein corona may affect photosynthesis in I. hawkeri.

Simultaneous determination of 18 common disinfection by-product residues in drinking water by high performance liquid chromatography-tandem mass spectrometry / 上海预防医学

ObjectiveA method was developed for the rapid determination of 18 common disinfection by-products including halogenated oxides and haloacetic acid （HAAs） in drinking water by high performance liquid chromatography tandem mass spectrometry （HPLC-MS/MS）. MethodThe water sample was filtered by 0.22 μm hydrophilic membrane then the analytes were separated on a PFP （2.1 mm× 100 mm， 2.7 μm） pentafluorophenyl column with 0.1% acetic acid and acetonitrile as mobile phase gradient elution. Ionization in anionic electrospray mode was detected by multi-reaction monitoring （MRM） mode. The external standard method was used for quantitation. ResultsThe correlation coefficients of 18 disinfection by-products were above 0.999 in the corresponding linear range. The average spiked recoveries of 1， 10 and20 times of LOQ of each analyte were 91.6%‒101.8%， and the relative standard deviation （RSD） was 1.2%‒6.4%. The LOD and LOQ were 0.020‒2 μg·L-1 and 0.050‒5 μg·L-1， respectively. ConclusionThis method is simple， sensitive and accurate， and could be used for the routine analysis of 18 common disinfection by-products in drinking water.

Study on Clinical Application and Supervision of LC-MS in in Vitro Diagnosis Test / 中国医疗器械杂志

From the perspective of technical evaluation, this study reviewed the current situation of application and clinical application of medical device products were detected by liquid chromatography-tandem mass spectrometry in the market in recent years. The regulatory requirements of these products in China, USA, EU and Japan were compared and analyzed, and the monitoring situation of adverse events after listing, the standards for reference and the domestic and foreign regulatory documents were combined, the clinical application and regulatory risks of the product were analyzed. The problems such as pre-treatment, system matching, adequacy of performance index requirements, inter-room consistency, reference interval and registration unit were discussed and suggestions for supervision were given, with a view to the field of product R&D and production, review and approval of supervision to provide technical reference.