Label-free target identification for natural products based on proteomics / 药学学报

Target identification and verification of natural products is an important and challenging work in the field of chemical biology. It is also an important job for researchers to apply chemical proteomics technology to biomedicine in order to identify target proteins of natural products. Target identification is critical to understanding its mechanisms and developing natural products as molecular probes and potential therapeutic drugs. Traditional approaches of small molecule target identification based on affinity have been shown to be successful, such as click-chemical probes, radioisotope labeling or photosensitized small-molecule probes. Nevertheless, these technologies require purified candidate target proteins, and modified small molecules with probes or linkers, such as adding agarose beads, biotin labels, fluorescent labeling or photo-affinity labeling. Many structure-activity relationship studies should be performed to ensure that the addition of small molecule labels undisturbed the original biological activity of the small molecules. Unfortunately, all these modifications are likely to alter their biological activity or binding specificity. To overcome the bottleneck of "target recognition", researchers have developed a series of new techniques for unmodified drug target identification. In this article, we reviewed the target identification techniques of natural product without structural modification in order to provide reference for the development of natural products.

Interaction proteomics of long noncoding rna uc431+ gene in postmenopausal osteoporosis / 中国组织工程研究

BACKGROUND: Overexpression of LncRNA TUG1 promotes osteoclast proliferation and inhibits apoptosis. Knockdown with siRNA has achieved the opposite result, indicating that knockdown of LncRNA TUG1 may become a potential target for osteoporosis treatment. OBJECTIVE: To study the proteins interacting with the non-coding RNA uc431+ associated with postmenopausal osteoporosis and carry out bioinformatics analysis. METHODS: Human monocytic leukemia cell line (THP-1) cells crosslinked with formaldehyde were broken by ultrasound. The experimental group was hybridized with magnetic beads combined with biotin labeled specific probes. The control group was hybridized with the magnetic beads of non-specific probes. The obtained peptides were identified using mass spectrometry. The data were searched and quantified by MaxQuant. The quantitative results of the two sets of samples were statistically analyzed, and the corresponding enrichment proteins were obtained. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, protein-protein interaction analysis and display were performed, and the protein-protein interaction network was constructed. RESULTS AND CONCLUSION: The total number of peptides obtained was 918, with 271 proteins in total, and the total number of proteins after filtration was 241. Compared with the control group, there were 10 differential proteins in the experimental group, including DDOST, DMBT1, HPD, IGLL5, IGK, LTF, LYZ, MUC5AC, PIGR, and RPL23. GO enrichment analysis showed that they were involved in biological processes such as defense reaction, leukocyte activation, ribosomal rRNA binding, lysozyme activity and other molecular functions. KEGG pathway analysis predicted that they were involved in ubiquinone and other terpenoid-quinone biosynthesis, phenylalanine metabolism, ribosome and salivary secretion. Combined with the analysis of proteomics and bioinformatics, it is predicted that uc431+, a gene related to postmenopausal osteoporosis, may be involved in immune regulation and bone metabolism by interacting proteins.

Analysis on volatile components in different parts of Asarum insigne by HS-GC-MS / 中草药

Objective To perform qualitative and quantitative analysis on the volatile components in roots, rhizomes, leaves, and flowers of Asari Radix et Rhizoma derived from Asarum insigne. Methods The volatile components were analyzed by HS-GC-MS, and the relative percentage content of each component was calculated with peak area normalization method. Results There were 58 components separated from four parts of A. insigne, including 27 common components in different parts. The principal constituents was trans-β-farnesene, safrole, and asaricin. Their contents were different in four parts. Especially the contents of safrole in rhizomes, leaves, and flowers were up to 34%, 22%, and 21%; The safrole in rhizomes was over twice higher than that in roots (12%). Because safrole was extremely poisonous, the rhizomes, leaves, and flowers should be used carefully. Conclusion The volatile components in A. insigne can be detected by HS-GC-MS simply and quickly. The research can be helpful for development and quality evaluation of A. insigne.

Screening and analysis of key active constituents in Guanxinshutong capsule using mass spectrum and integrative network pharmacology / 中国天然药物

Guanxinshutong capsule (GXSTC) is an effective and safe traditional Chinese medicine used in the treatment of cardiovascular diseases (CVDs) for many years. However, the targets of this herbal formula and the underlying molecular mechanisms of action involved in the treatment of CVDs are still unclear. In the present study, we used a systems pharmacology approach to identify the active ingredients of GXSTC and their corresponding targets in the calcium signaling pathway with respect to the treatment of CVDs. This method integrated chromatographic techniques, prediction of absorption, distribution, metabolism, and excretion, analysis using Kyoto Encyclopedia of Genes and Genomes, network construction, and pharmacological experiments. 12 active compounds and 33 targets were found to have a role in the treatment of CVDs, and four main active ingredients, including protocatechuic acid, cryptotanshinone, eugenol, and borneol were selected to verify the effect of (GXSTC) on calcium signaling system in cardiomyocyte injury induced by hypoxia and reoxygenation. The results from the present study revealed the active components and targets of GXSTC in the treatment of CVDs, providing a new perspective to enhance the understanding of the role of the calcium signaling pathway in the therapeutic effect of GXSTC.

Differential Proteomics Analysis of Endometriosis in Blood Stasis Syndrome / 中国结合医学杂志

OBJECTIVE@#To investigate the innate characters of 3 endometriosis (EMT) syndromes, blood stasis (BS), qi stagnation and blood stasis (QSBS) as well as Shen (Kidney) deficiency and blood stasis (KDBS) in terms of proteomics, lay a molecular biological basis for the differentiation of various blood stasis syndromes of EMT, establish a EMT microscopic syndrome differentiation and diagnosis system in terms of proteomics, discover the evolution principles and therapeutic targets of these EMT syndromes, and search their signifificant molecular markers and genetic intervention targets.@*METHODS@#Six specimens from the ectopic and entopic endometrium tissues of patients with EMT in each syndrome, BS, QSBS as well as KDBS, in the early proliferative phase of the menstrual cycle, and 6 specimens from normal endometrium tissues in the early proliferative phase of the menstrual cycle were obtained. Three groups were formed in each syndrome by mixing two random specimens in equal amount, and then their respective two-dimensional electrophoresis graphs were obtained after total protein extraction. Finally, the detected differences in protein expression were identifified through matrix-assisted laser desorption Ionization-time of flflight mass spectrometry (MALDI-TOF/MS) and protein database.@*RESULTS@#The results of differential proteins expressed in each syndrome were shown as follows: BS syndrome had 2 differential proteins in entopic endometrium and 1 differential protein in ectopic endometrium; KDBS syndrome had 3 in entopic endometrium and 3 in ectopic endometrium; and QSBS syndrome had 3 in entopic endometrium and 4 in ectopic endometrium. It was found out that annexin was highly expressed in both entopic and ectopic endometrium of KDBS syndrome; and myosin light chain 3 was highly expressed in both entopic and ectopic endometrium of QSBS syndrome.@*CONCLUSION@#There are differential protein expressions among the 3 EMT syndromes, which might be the inner origin of syndrome characters, and these differential proteins might be the candidate biomarkers for the pathogenesis of various EMT syndromes.

Screening and analysis of key active constituents in Guanxinshutong capsule using mass spectrum and integrative network pharmacology / 中国天然药物

Guanxinshutong capsule (GXSTC) is an effective and safe traditional Chinese medicine used in the treatment of cardiovascular diseases (CVDs) for many years. However, the targets of this herbal formula and the underlying molecular mechanisms of action involved in the treatment of CVDs are still unclear. In the present study, we used a systems pharmacology approach to identify the active ingredients of GXSTC and their corresponding targets in the calcium signaling pathway with respect to the treatment of CVDs. This method integrated chromatographic techniques, prediction of absorption, distribution, metabolism, and excretion, analysis using Kyoto Encyclopedia of Genes and Genomes, network construction, and pharmacological experiments. 12 active compounds and 33 targets were found to have a role in the treatment of CVDs, and four main active ingredients, including protocatechuic acid, cryptotanshinone, eugenol, and borneol were selected to verify the effect of (GXSTC) on calcium signaling system in cardiomyocyte injury induced by hypoxia and reoxygenation. The results from the present study revealed the active components and targets of GXSTC in the treatment of CVDs, providing a new perspective to enhance the understanding of the role of the calcium signaling pathway in the therapeutic effect of GXSTC.

Análisis espectroscópico del precipitado formado de la mezcla de Hipoclorito de Sodio y Clorhexidina . Estudio In Vitro . Parte II

l objetivo de este estudio fue analizar el precipitado formado por la interacción de dos disoluciones acuosas: una de hipoclorito de sodio al 5.25% y otra de gluconato de clorhexidina al 2%, por medio de cromatografía de capa fina (TLC) y un análisis detallado de espectroscopia de resonancia magnética nuclear (RMN-¹H a 600 MHz y RMN-¹³C a 100 MHz) en una y dos dimensiones. Para esto, se establecieron 3 grupos de estudio: el Grupo A correspondiente a gluconato puro de clorhexidina que fue liofilizado y secado al vacío, el Grupo B: los precipitados obtenidos al combinar 2 ml de la disolución de gluconato de clorhexidina con 2 ml de la disolución de hipoclorito de sodio y el Grupo C, una muestra comercial de PCA (4-Cloroanilina 98%,). El sólido correspondiente al grupo B, fue lavado, centrifugado y seco en estufa de vacío sin calentamiento por más de 72 horas. Una vez seco, se corrieron placas de capa fina (TLC) en diversas mezclas de elución, y se encontró que el precipitado consistía de una mezcla compleja de sustancias similares a la clorhexidina y que no poseía PCA. Los análisis de espectroscopia de resonancia magnética nuclear mostraron que la señal del carbono base del grupo amino de la PCA, a δ/146.5 ppm (grupo C), no se encontraba en el espectro de ¹³C de las muestras del grupo B lo que implica, la ausencia de PCA en la muestra B. El análisis del grupo B por medio de la misma técnica, mostró una mezcla compleja de señales que corresponden probablemente, a estructuras similares a la clorhexidina y a potenciales derivados aromáticos con una estructura similar a esta, nuevamente, no se encuentran evidencias de PCA.

he aim of this study was to analyze the precipitate formed by the mixture of 5,25% sodium hypochlorite (NaOCl) and 2% chlorhexidine (CHX) through thin layer chromatography and nuclear magnetic resonance spectroscopy (RMN-¹H, 600 MHz and RMN-¹³C to 100 MHz) 1D and 2D spectra. Thus, the following groups were established: Group A corresponds to a pure freeze-dried chlorhexidine gluconate , Group B made-up by a combination of 2ml of chlorhexidine 2% and sodium hypochlorite 5.25% and Group C was a commercial sample of PCA (4-Chloroaniline 98%). The samples of group B were rinsed with distillated water and spinned during 15 minutes at 25°C, the supernatant was eliminated by vacuum and vacuum chamber for 72 hours without heating. Finally, the solid was grinded and dried in vacuum chamber for 24 hours without heating. Thin layer chromatography, shows that sample B were composed by more than one chemical substance and Chlorexidine, the RMN-¹³C showed that the signal of the amino group characteristic of PCA appears down field (δ/146.5 ppm) in C group, meanwhile in group B appears up field (δ/129ppm), which demonstrates the absence of PCA during the process. The analysis of Group B by RMN-¹³C results also, in different signals of low intensity that correspond to similar structures to chlorhexidine and potential aromatics derivatives with similar characteristics structures to chlorhexidine.

Metabolic profiling of the nephrotoxicity of realgar nanoparticles in rats / 中国药科大学学报

The effect of realgar nanoparticles (NPs) on endogenous small molecules in rat kidney was analyzed by mass spectrometry-based metabolomics.The relationship between the changes of metabolites and the nephrotoxicity of realgar NPs was also discussed to provide a basis for the further toxicity study and the clinical application of realgar NPs.SD rats were randomly divided into seven groups,including control group,three doses (40,200,1 000 mg/kg) of relegar and realgar NPs groups,respectly.After 28 days of continuous intragastric administration,all rats were sacrificed and their serum and kidney samples were collected.The toxic effect of realgar NPs on kidney tissues were examined by biochemical analysis and histopathologic examination,which revealed a dosedependent nephrotoxicity induced by realgar NPs.The LC-MS and GC-MS analysis were performed for the subsequent metabolomics study.A series of 32 metabolites were found to be altered significandy in the kindey of realgar NPs treated rats,and might serve as potential nephrotoxicity biomarkers.The results of metabolic pathway analysis indicated that the nephrotoxicity of realgar NPs might be associated with the disorders of the amino acids and phosphatidic acid metabolism.

Determination of volatile components in Tibetan medicine Heracleum millefolium by HS-GC-MS / 中草药

Objective: To establish a rapid analytical method for volatile components in Tibetan medicine Heracleum millefolium and to determine the volatile components from its roots, stems, leaves, and flower parts, respectively. Methods: Headspace sampling incorporation with gas-chromatography-mass spectrum (HS-GC-MS) determination was introduced to analyze the powder directly. Static headspace equilibration was performed at 100℃ for 40 min, and 1 mL of the headspace gas was injected in split mode of 10:1. The split inlet temperature was 260℃. The carrier gas was He at a constant flow rate of 1.8 mL/min. The column oven temperature was initially set at 50℃ for 2 min, then increased to 100℃ at 2℃/min, held for 6 min, then increased to 300℃ at 10℃/min and held for 2 min. The GC/MS interface temperature was maintained at 280℃. The solvent delay time was 3 min (to bypass the solvent peak). The volatile components were confirmed by NIST11.L database, and volatile organic compounds from roots, stems, leaves, and flower parts were compared. Results: The types of compounds in the roots, stems, leaves, and flowers of H. millefolium are mainly aldehyde, benzene, alcohols, and alkene. Octanal, hexanal, and γ-terpinene are the main components in the roots and stems. While o-isopropyltoluene and terpinolene are the main components in the leaves and flowers. Conclusion: HS-GC-MS method is easy, simple, and feasible, and can be widely used in other Chinese materia medica samples for analysis of volatile components.

Correlation Research on Photodegradation Products of Cobamamide / 中国药师

Objective:To research the correlation between the cobamamide photodegradation products in the visible light area at different wavelengths and the photodegradation rate intensity. Methods:The 40-minute illumination experiment was conducted for co-bamamide reference solution respectively at the wavelength of 400 nm,450 nm,500 nm,550 nm,600 nm,650 nm and 700 nm under the illumination of 50 Lx,100 Lx,200 Lx,300 Lx,400 Lx and 500 Lx,respectively. An HPLC method was used to detect the cobam-amide content after the irradiation, the contents and proportions of hydroxocobalamin and adenosine (two photodegradation products) were calculated and the two photodegradation products were confirmed by mass spectrum. Results:The main photodegradation products of cobamamide (impurity 1,adenosine and hydroxocobalamin) had the similar photodegradation tendency. Within the scope of 50 Lx-200 Lx,the illumination intensity affected the concentration ratio of hydroxocobalamin and adenosine obviously. Within the scope of 200 Lx-500 Lx,the illumination intensity showed smaller effect. Under the different wavelengths and photodegradation rate intensity, the content of hydroxocobalamin was higher than that of adenosine under the same experimental condition.Conclusion:This paper re-searched the cobamamide photodegradation products in the optimum dark condition. The method is accurate and reliable,which can be used for the control of photodegradation related substances of cobamamide.

Analysis of metabolites and metabolic pathway of 5F-AMB in vitro using UPLC-HR-MS / 药学学报

This study was designed to investigate the metabolites of 5F-AMB by human liver microsomes model in vitro. 5F-AMB was added in the reaction mixture to simulate the metabolic process in human hepatocytes in vivo, and then to determine the reaction points and pathways of metabolism by ultra performance liquid chromatography (UPLC) coupled to high resolution mass spectrum (HR-MS). 5F-AMB generated 9 metabolites in total in the human liver microsomes model. Ester hydrolysis, combination of ester hydrolysis and oxidative defluorination, combination of ester hydrolysis and hydroxylation on pentyl chain moiety and combination of ester hydrolysis and hydroxylation on indazole ring moiety reactions were its main metabolic pathways. The method is fast and efficient so that the ester hydrolysis, combination of ester hydrolysis and oxidative defluorination, combination of ester hydrolysis and hydroxylation on pentyl chain moiety and combination of ester hydrolysis and hydroxylation on indazole ring moiety metabolites of 5F-AMB can be used as the suitable and potential biomarkers in the urine samples.

The research progress of protein lysine succinylation / 医学研究生学报

Recently the lysine succinylation was discovered in vivo, and it was demonstrated to be widely involved in cell dif-ferentiation, cell metabolism and other important physiological activities.Lysine succinylation has become the forefront of life science research.Scientists have provided a lot of evidences that proteins in prokaryotes and eukaryotes are widely succinylated, without which the central metabolism and intermediary metabolism of many metabolic enzymes are disrupted.To better understand the importance of Succinylation in vivo, protein-succinyl modification of the current research and the latest developments are reviewed, which summarize succinylated protein lysine sites in the center of important physiological metabolic pathways, diseases and other pathological conditions.

Analysis of CUMS-induced differentially expressed proteins in rat hippocampus by ITRAQ / 中国药理学通报

Aims To compare hippocampus between CUMS rats and normal rats, to find differentially ex-pressed proteins and to explore the pathogenesis of de-pression in the protein levels and biological marker. Methods Chronic unpredicted mild stress was taken to establish rat depression model. The ITRAQ-labeled proteins and peptides were separated by the cation col-umn, and differentially expressed proteins were detec-ted and identified by 2D LC-MS/MS. The functions of proteins were analyzed by bioinformatics. Results To-tally 5 109 proteins were identified, 33 differentially expressed proteins were identified, the expressions of 8 proteins were increased and 25 proteins downregulated. Conclusion ITRAQ based sereening is effective in discovering the nosogenesis of depression and new bio-logical marker.

Rapid identification of chemical components in Congrong Zonggan capsule by UPLC-Q-TOF-MS/MS / 中国中药杂志

This study was aimed to qualitatively analyze the chemical components in Congrong Zonggan capsule by using ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry method (UPLC-Q-TOF-MS/MS). An Agilent SB-C₁₈ Rapid Resolution HD (3.0 mm×100 mm,1.8 μm) was used with acetonitrile (A) - 0.1% formic acid solution (B) as the mobile phase for gradient elution. The flow rate was 0.2 mL•min⁻¹; the detection wavelength was set at 330 nm and the column temperature was maintained at 30 ℃. Electrospray ion (ESI) source was applied for the qualitative analysis under the negative ion mode. Finally, based on comparison with standard samples, database matching analysis and reviewing relevant literature, 41 compounds were identified from Congrong Zonggan capsule. This method could be used to rapidly detect the chemical components in Congrong Zonggan capsule, providing reference for the quality control of Congrong Zonggan capsule and laying a foundation for the further study on active components mechanism.

Analysis of mass spectrometric detection in 21 neonatal with neonatal intrahepatic cholestasis disease / 实用医学杂志

Objective To analyze blood Met、 Phe 、Tyr、 Arg、 Cit、 Orn、 Ser、 Thr、 C0、 C2、 C3、 C14、C14 ∶ 1 , C16 , C16 ∶ 1 , C18 , C18 ∶ 1 and urine 4-OH-PHPLA , 4-OH-PHPPA level of NICCD patient and discuss the application value of diagnosis NICCD. Methods From May 2011 to May 2015, 21 NICCD patient were diagnose in Guangxi Newborn Screening Center. Meanwhile, 100 normal children were selected as the control group. Blood Met, Phe, Tyr and other factors and urine 4-OH-PHPLA, 4-OH-PHPPA level were analyzed by SPSS. Results In the experimental group, blood Met, Phe, Tyr and many other indexes and urine 4-OH-PHPLA, 4-OH-PHPPA level were higher and blood Orn/Cit were lower than the control group(P 0.05). Conclusion NICCD patient has abnormal biochemical index. Blood test by TMS and urine test by GC-MS are very important in NICCD diagnosis.

Flexible Device for Direct Analysis in Real Time without Grid Electrode for Mass Spectrum Analysis / 分析化学

The paper presents a flexible and simple direct analysis in real-time ( DART) device without grid electrode for mass spectrometer injection. It contained inert carrier gas, ionizer, heater and temperature-controller etc. Excluding the grid electrode and then reducing the structure units, the device could be easy to build up in low cost and flexible to connect with a variety of mass spectrometers. The experimental conditions like the kind of carrier gas, flow rate and temperature were investigated for the device. By using argon as carrier gas, flow rate as 7. 5 L/min, and temperature of heat tape as 300 ℃, the device was used to analyze benzene alcohol, linoleic acid, dichlorvos emulsion, mosquito coils, citrus peel, and sample ( propranolol hydrochloride) on thin-layer plate combined with mass spectrometer. The results were accurate and the device was stable and reliable.

Simultaneous Determination of 20 Anti-Obesity Drugs Illegally Added in Weight-loss Functional Foods by Matrix Solid Phase Dispersion-High Performance Liquid Chromatography Tandem Mass Spectrometry / 分析化学

An analytical method based on high performance liquid chromatography tandem mass spectrometry has been developed for the simultaneous determination of 20 anti-obesity drugs ( fenfluramine, phenylpropanolamine, sibutramine, sertraline, rimonabant, bupropion, citalopram, fluoxetine, benfluorex, topiramate, zonisamide, caffeine, phenolphthalein, emodin, indapamide, bumetanide, torasemide, triamterene, orlistat, phenformin). that were extracted from various weight-loss functional foods by ethanol-acetone(7:3, V/V)and purified by primary secondary amine (PSA) and octadecyltrimethoxysilane(ODS) under ultrasonication. The analysis was carried out on HPLC-MS /MS by electrospray ionization using multiple reaction monitoring after the chromatographic separation on Waters Atlantis T3 (3 μm, 150 mm × 2. 1 mm) column. Identification was achieved by the retention time and the ion ratio, quantification was done by the external standard method. The limits of detection for the appetite suppressants were 0. 05-3. 0 mg/kg. The mean recoveries at the three spiked levels were 67 . 1%-101 . 4%, with the intra-day precision less than 10%and the inter-day precision less than 15%. The method is reliable, accurate, reproducible and suitable for the determination of the anti-obesity drugs in different weight-loss functional foods.

Serum metabolic profiling and screening of characteristic metabolites before and after partial hepatectomy for HBV-related liver cancer / 中华肝胆外科杂志

Objectives To investigate the characteristics of changes in serum metabolic profile before and after resection of carcinoma tissues to establish a disease distinguishing model,to analyze the changing trend of characteristic metabolites,and to determine the molecular mechanism and potential clinical value of characteristic metabolic markers for HBV-related liver cancer.Methods Ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) was used to analyze the serum metabolites of 15 patients with hepatocellular carcinoma (HCC) before and after partial hepatectomy and on 25 healthy volunteers.The pattern recognition method and nonparametric test analyzes were used to analyze the data and to identify the specific metabolites and their changes after resection of carcinoma tissues.Results We established the principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) disease distinguishing model for HCC patients before and after operation as against the healthy volunteers.To distinguish between the liver cancer group and the normal control group,27 characteristic metabolites were selected from the patients before and after resection of carcinoma tissues.Eight moved towards the normal control after resection of carcinoma tissues.This indicated that liver carcinoma was an important impacting factor for these metabolites.Finally,7 metabolites were identified,and these metabolites had high diagnostic value as shown on ROC curves.Conclusions Through serum metabolic profiling of patients before and after resection of carcinoma tissues,a high correlation between metabolism and hepatocellular carcinoma was found.Researches on endogenous metabolites and pathways in liver diseases will provide a better understanding of the molecular mechanisms and provide further directions for clinical diagnosis and treatment.

Effect of ginkgolide B-loaded self microemulsifying drug deliver system on pharmacokinetics of ginkgolide B in retina / 中华实验眼科杂志

Background Ginkgolide B (GB) has been proved to have neuroprotective and anti-apoptotic effects and can effectively inhibit apoptosis of retinal photoreceptor cells.But the high hydrophobic feature and low bioavailability of GB limit its clinical application.Self microemulsifying drug delivery system (SMEDDS) can effectively improve the infusibility drug dissolution and bioavailability in the retina.Objective This study was to investigate the pharmacokinetics and drug-time change of GB-loaded SMEDDS in retina.Methods Eighty SD rats were randomized into 2 groups,2.5％ GB(40 mg/kg) of SMEDDS or GB suspension(0.1％ DMSO dissolve) were gastrically given respectively in two groups.The rats were sacrificed and retinas were isolated 15,30,45 minutes and 1 hour,2,4,8,12 hours to prepare the retinal suspension.The content of GB in retina was assayed with high performance liquid chromatography-electrospray ionization-(1) (1)ss spectrum (HPLC-ESI-MS) and contrasted with standard curve.Practical drug dynamics program 3p87 was used to detect the pharmacokinetics parameters.The maximal content(Cmax,mg/g),time to peak (Tmax,h),clearance ratio (Ke/h),high-life period (t1/2) and area under the concentration-time curve(AUC0-∞,mg/(g · h)) of GB in various time points in retina after a single oral dose were calculated and compared between two groups.Results The standard curve was obtained over the concentration range of 1-32 mg/L with a linear regression equation,Y =0.0732X + 0.056 (r =0.992).A similar content-time curve was seen between GB suspension group and GB-SMEDDS group.The GB content was higher in GB-SMEDDS group than that in GB suspension group from 30 minutes through 12 hours after administration of drugs.The Cmax of GB-SMEDDS group and GB suspension group were(15.83±1.84) mg/g and(2.65±0.10) mg/g,the AUC0-∞ were(15.30±0.11)mg/(g· h)and(6.42±0.19)mg/(g · h).Conclusions HPLC-ESI-MS is proved to be a rapid,accurate,sensitive and suitable method for pharmocokinetic study of GB.SMEDDS can raise the concent of GB in retina,and it probably improve the bioavailability of GB.

Simultaneous Determination of 11 Appetite Suppressants in Weight-loss Functional Foods by Accelerated Solvent Extraction- High Performance Liquid Chromatography Tandem Mass Spectrometry / 分析化学

An analytical method based on high performance liquid chromatography tandem mass spectrometry has been developed for the determination of 11 appetite suppressants (fenfluramine,phenylpropanolamine,sibutramine,sertraline,rimonabant,bupropion,citalopram,fluoxetine,benfluorex,topiramate,zoni-samide). Various weight-loss functional foods were extracted under accelerated solvent extraction and separated on Waters Atlantis T3( 150 mm×2.1 mm,3μm) column. The analysis was carried out on HPLC-MS/MS by electrospray ionization using multiple reaction monitoring. Identification was achieved by ihe retention time and the ion ratio,quantification was done by the external standard curves. The limits of detection for the appetite suppressants were 0.05-4.0 mg/kg. The mean recoveries at the three spiked levels(low,middle,high) were 78.3% - 103. 6% ,with the intra-day precision less than 12% and the inter-day precision less than 15%. The method is reliable,sensitive,reproducible,and adapts to the determination of the appetite suppressants in different weight-loss functional foods.