Network pharmacology-based exploration of pathways involved in the inhibition of hepatocellular carcinoma cell proliferation by Oxymatrine

Objective:To explore the effect of Oxymatrine(OMT)on hepatocellular carcinoma cells and its possible action pathways.Methods:The core targets of Oxymatrine action in hepatocellular carcinoma were identified using network pharmacology and validated using in vitro experiments.CCK8 assay and scratch assay were used to detect the effects of Oxymatrine on the proliferation and migration of MHCC97H(TP53 mutant)cells,and Western blot assay and qPcr assay were used to find out the expression of the core targets after Oxymatrine acted on MHCC97H cells at the protein level and mRNA level,respectively.Results:Network pharmacology showed that the core target was TP53 protein;CCK8 assay showed that the IC50 at 24 h and 48 h was 9.64 mg/ml and 7.47 mg/ml,respectively;Scratch assay proved that Oxymatrine markedly inhibited the migratory ability of MHCC97H cells;Western blot assay and qPcr assay found that TP53 gene expression was down-regulated.The western blot experiment and qPcr experiment found that TP53 gene expression was down-regulated.Conclusions:Oxymatrine significantly inhibited the proliferation and migration of hepatocellular carcinoma MHCC97H cells,and its mechanism of action may be related to TP53.

Simultaneous determination of five plant hormones in cotton leaves using QuEChERS combined with HPLC‒MS/MS

Background Plant hormones profoundly influence cotton growth,development,and responses to various stresses.Therefore,there is a pressing need for an efficient assay to quantify these hormones in cotton.In this groundbreaking study,we have established QuEChERS-HPLC‒MS/MS method,for the simultaneous detection of multiple plant hormones in cotton leaves,allowing the analysis and quantification of five key plant hormones.Results Sample extraction and purification employed 0.1%acetic acid in methanol and C18 for optimal recovery of plant hormones.The method applied to cotton demonstrated excellent linearity across a concentration range of 0.05–1 mg・L−1,with linear regression coefficients exceeding 0.99.The limits of quantification(LOQs)were 20μg・kg−1 for GA3 and 5μg・kg−1 for the other four plant hormones.Recovery rates for the five plant hormones matrix spiked at levels of 5,10,100,and 1000μg・kg−1 were in the range of 79.07%to 98.97%,with intraday relative standard deviations(RSDs)ranging from 2.11%to 8.47%.The method was successfully employed to analyze and quantify the five analytes in cotton leaves treated with plant growth regulators.Conclusion The study demonstrates that the method is well-suited for the determination of five plant hormones in cotton.It exhibits excellent selectivity and sensitivity in detecting field samples,thus serving as a robust tool for indepth research into cotton physiology.

Rapid Analysis of Four Alkaloids in Uncaria rhynchophylla by Core-Shell Column HPLC and Quantitative Analysis of Multi-Components by Single Marker(QAMS)

As a traditional herbal medicine,the major alkaloids in Uncaria rhynchophylla have been proven to have blood pressure-lowering and sedative effects.It is essential to develop an effective method for the determination of the major alkaloids in U.rhynchophylla.In this research,a rapid quantitative analysis involving multi-components analysis by a single marker strategy coupled with core-shell column HPLC was adopted to analyse four alkaloids(corynoxeine,isocorynoxeine,isorhynchophylline,rhynchophylline)in U.rhynchophylla.Isorhynchophylline was selected as the internal reference substance,the content of which was determined by the traditional external standard method.Relative correction factors(RCF)between isorhynchophylline and the other three alkaloids were calculated respectively.The results showed that the QAMS method had good robustness under different HPLC instruments.Nineteen batches of U.rhynchophylla were tested.No significant difference was observed between the results by QAMS and EMS(Correlation coefficient>0.99,p>0.05).The QAMS method could be employed as a rapid,effective technique for the quality control of U.rhynchophylla.

Evaluation of Uncertainty for Determination of Stevioside Content in Fermented Milk by HPLC

[Objectives]The paper was to establish an evaluation method for the uncertainty of stevioside(including stevioside,rebaudioside A,rebaudioside B,rebaudioside C,rebaudioside F,Dulcoside A,rubusoside and steviolbioside)content determination in fermented milk based on HPLC.[Methods]The mathematical model of stevioside content and the propagation rate of uncertainty were established,and the sources of uncertainty were analyzed.[Results]The uncertainty mainly came from four main aspects,including standard uncertainty u(C)introduced by solution concentration C,standard uncertainty u(V)introduced by sample volume V,standard uncertainty u(m)introduced by sample mass m weighing and standard uncertainty u(f_(rep))introduced by measurement repeatability of stevioside content after sample dissolution and constant volume.The uncertainty estimation table and fishbone chart of stevioside content X determination were established.The relative synthetic standard uncertainty of stevioside content was obtained,and the standard uncertainty was extended to form the measurement result of stevioside content and its uncertainty report.[Conclusions]The evaluation results can be directly applied to the daily practical detection work.

Validation of a Method for the Measurement of Caffeine in Water by HPLC-UV

For the production of a reference material from caffeine solution, one of the methods of characterization was HPLC-UV since caffeine is very sensitive to the UV. In this work, a batch solution of caffeine in water reference material of 1000 mg/kg has been gravimetrically prepared using a calibrated analytical balance. A sample of this solution was diluted to 25 mg/kg for measurement by HPLC-UV in the range 10 - 50 mg/kg. The chromatographic separation was carried out by C-18 column and a mobile phase assembled of 75% water and 25% methanol (v:v). The detection was made by the UV detector at 275 nm. The validation of this analytical method was carried out in accordance with requirements of the EURACHEM and ICH guidelines. The selectivity, linearity, accuracy, precision and trueness (recovery and bias) of the method were studied. The validation results proved that the method is fit-for-purpose of measuring the caffeine concentration in water in the range 10 - 50 mg/kg using HPLC-UV.

Silver-ion HPLC测定1,3-二油酸-2-棕榈酸三酰甘油的含量

准确测定1,3-二油酸-2-棕榈酸三酰甘油(OPO)的含量,建立了一种以高效液相色谱结合银离子交换柱(Silver-ion HPLC)的测定方法。以ChromSpher 5 Lipid(25 cm×4.6 mm,5μm)银离子交换柱通过HPLC正相系统分离三酰甘油,配合蒸发光散射检测器(ELSD),以毒性较小的二氯甲烷和丙酮为流动相。流速0.6 mL/min,柱温30℃。漂移管温度30℃,空气压力0.35 MPa。在此条件下,1,3-二油酸-2-棕榈酸三酰甘油和1,2-二油酸-3-棕榈酸三酰甘油两种同分异构体基本达到分离,样品出峰完整,峰形良好。OPO色谱峰面积的自然对数与浓度的自然对数呈良好的线性关系(R2=0.998 8)。用该方法测定了母乳脂肪、实验室合成结构油脂样品、商品结构油脂、棕榈油和山茶油中OPO的含量。结果表明该方法的灵敏度高、重现性良好。

Effect of oxymatrine on the replication cycle of hepatitis B virus in vitro

AIM:To determine the antiviral mechanism or target of oxymatrine against hepatitis B virus(HBV).METHODS:HepG2.2.15 cells were incubated with culture medium containing 500 μg/mL of oxymatrine for 2 and 5 d.The surface antigen of HBV(HBsAg) and e antigen of HBV(HBeAg) in supernatant were determined by ELISA.HBV DNA in supernatant,and intracellular covalently closed circular DNA(cccDNA),relaxed circular DNA(rcDNA) and pregenomic RNA(pgRNA) were quantif ied by specif ic real-time polymerase chain reaction(PCR) or reverse transcription(RT)-PCR.RESULTS:Treatment with oxymatrine for 2 d and 5 d reduced the production of HBV by the cell line,as indicated by the decline of HBsAg(22.67%,t = 5.439,P = 0.0322 and 22.39%,t = 5.376,P = 0.0329,respectively),HBeAg(55.34%,t = 9.859,P = 0.0101 and 43.97%,t = 14.080,P = 0.0050) and HBV DNA(40.75%,t = 4.570,P = 0.0447 and 75.32%,t = 14.460,P = 0.0047) in the supernatant.Intracellular cccDNA was also markedly reduced by 63.98%(t = 6.152,P = 0.0254) and 80.83%(t = 10.270,P = 0.0093),and intracellular rcDNA by 34.35%(t = 4.776,P = 0.0413) and 39.24%(t = 10.050,P = 0.0097).In contrast,intracellular pgRNA increased by 6.90-fold(t = 8.941,P = 0.0123) and 3.18-fold(t = 7.432,P = 0.0176) after 500 μg/mL of oxymatrine treatment for 2 d and 5 d,respectively.CONCLUSION:Oxymatrine may inhibit the replication of HBV by interfering with the process of packaging pgRNA into the nucleocapsid,or inhibiting the activity of the viral DNA polymerase.

Role of DOR-β-arrestin1-Bcl2 Signal Transduction Pathway and Intervention Effects of Oxymatrine in Ulcerative Colitis

This study was aimed to investigate the role of the delta-opioid receptor （DOR）-β-arrestinl-Bcl-2 signal transduction pathway in the pathogenesis of ulcerative colitis （UC） and the intervention effects of oxymatrine on UC. Forty Sprague-Dawley rats were divided into nor- mal group, model group, oxymatrine-treated group and mesalazine-treated group （n=10 each） at ran- dom. The rat UC model was established by intra-colonic injection of trinitrobenzene sulfonic acid in the model group and two treatment groups. The rats in oxymatrine-treated group were subjected to intramuscular injection of oxymatrine [63 mg/（kg·day）] for 15 days, and those in mesalazine-treated group given mesalazine solution [0.5 g/（kg·day）] by gastric lavage for the same days. Animals in normal group and model group were administered 3 mL water by gastric lavage for 15 days. On the 16th day, after fasting for 24 h, the rats were sacrificed for the removal of colon tissues. The expres- sion levels of DOR, β-arrestinl and Bcl-2 were determined in colon tissues by immunohistochemistry and real-time quantitative polymerase chain reaction （RT-PCR）, respectively. It was found that the expression levels of DOR, [3-arrestinl and Bcl-2 protein and mRNA were significantly increased in the model group as compared with the other groups （P〈0.05）. They were conspicuously decreased in both mesalazine-treated and oxymatrine-treated groups in contrast to the model group （P〈0.05）. No statistically significant difference was noted in these indices between mesalazine- and oxyma- trine-treated groups （P〉0.05）. This study indicated that the DOR-β-arrestinl-Bcl-2 signal transduc- tion pathway may participate in the pathogenesis of UC. Moreover, oxymatrine can attenuate the de- velopment of UC by regulating the DOR-β-arrestin 1-Bcl-2 signal transduction pathway.

Inhibitory effect of oxymatrine on hepatocyte apoptosis via TLR4/PI3K/Akt/GSK-3β signaling pathway

AIM To evaluate the effect of oxymatrine(OMT) on hepatocyte apoptosis in rats with lipopolysaccharide(LPS)/D-galactosamine(D-Gal N)-induced acute liver failure(ALF). METHODS LPS/D-Gal N was used to establish a model of ALF in rats. To evaluate the effect of OMT, we assessed apoptosis by transmission electron microscopy, and the pathological changes in the liver by light microscopy with hematoxylin and eosin staining. An automated biochemical analyzer was used to measure serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST). Enzyme-linked immunosorbent assay was used to determine the levels of tumor necrosis factor(TNF)-α and interleukin(IL)-1β. Western blotting was used to detect protein levels in liver tissues. Streptavidin peroxidase immunohistochemistry was used to observe expression of Toll-like receptor(TLR)4, active caspase-3, Bax and Bcl-2. RESULTS All rats in the normal control and OMT-pretreated groups survived. The mortality rate in the model group was 30%. OMT preconditioning down-regulated apoptosis of hepatocytes and ameliorated pathological changes in liver tissue. The levels of AST, ALT, TNF-α and IL-1β in the model group increased significantly, and were significantly reduced by OMT pretreatment. OMT pretreatment down-regulated expression of TLR4 and active caspase-3 and the Bax/Bcl-2 ratio, and upregulated expression of P-AktSer473(Akt phosphorylated at serine 473) and P-GSK3βSer9(glycogen synthase kinase 3β phosphorylated at serine 9) induced by LPS/D-Gal N. CONCLUSION OMT inhibits hepatocyte apoptosis by suppressing the TLR4/PI3K/Akt/GSK-3β signaling pathway, which suggests that OMT is an effective candidate for ameliorating acute liver failure.

Effects of Oxymatrine on the Apoptosis of Human Esophageal Carcinoma Eca109 Cell Line and Its Mechanism

The effects of Oxymatrine （Oxy） on the proliferation and apoptosis of human esophageal carcinoma Ecal09 cell line and the mechanism were investigated. The human esophageal carcinoma Eca 109 celis were cultured in vitro. The Oxy-induced apoptosis of Eca 109 cells was assayed by using flow cytometry. The expressions of p-ERKII2, Cyclin D1, p21^waf/cipl, Bax and Bcl-2 were detected by Western blot. Flow cytometry revealed that Oxy could induce the apoptosis of Eca l09 cells. Western blot showed that Oxy of different concentrations suppressed the expressions of p-ERK1/2, Cyclin D1 and Bcl-2, but up-regulated the expression of p21waf/cip1 and Bax, and the ratio of Bax/Bcl-2 was increased. It was suggested the Oxy could induce the apoptosis of Eca l09 cells, which might be related to the upregulation of p21waf/cip1 and the downregulation of p-ERK1/2, Cyclin D1 and p21^waf/cip1. The possible pathway may be related to Bcl-2/Bax.

Oxymatrine reduces neuroinflammation in rat brain A signaling pathway

Cerebral neuroinflammation models were established by injecting 10μg lipopolysaccharide into the hippocampus of male Sprague-Dawley rats. The rats were treated with an intraperitoneal injection of 120, 90, or 60 mg/kg oxymatrine daily for three days prior to the lipopolysaccharide injection. Twenty-four hours after model induction, the hippocampus was analyzed by real-time quantitative PCR, and the cerebral cortex was analyzed by enzyme-linked immunosorbent assay and western blot assay. The results of the enzyme-linked immunosorbent assay and the real-time quantitative PCR showed that the secretion and mRNA expression of the pro-inflammatory cytokines interleukin-113 and tumor necrosis factor-a were significantly decreased in the hippocampus and cerebral cortex of model rats treated with oxymatrine. Western blot assay and real-time quantitative PCR analysis indicated that toll-like receptor 4 mRNA and protein expression were significantly decreased in the groups receiving different doses of oxymatrine. Additionally, 120 and 90 mg/kg oxymatrine were shown to reduce protein levels of nuclear factor-KB p65 in the nucleus and of phosphorylated IKBa in the cytoplasm of brain cells, as detected by western blot assay. Experimental findings indicate that oxymatrine may inhibit neuroinflammation in rat brain via downregulating the expression of molecules in the toll-like receptor 4/nuclear factor-KB signaling Dathwav.

替米沙坦血药浓度 HPLC 测定方法的研究

目的:建立替米沙坦血药浓度的高效液相-荧光色谱分析方法。方法:以依贝沙坦为内标,血浆样品用乙腈沉淀蛋白,色谱柱:Inersil ODS C_(18)色谱柱,(5μm,150mm×4.6mm),在线过滤器;流动相为水相(0.25%三乙胺水溶液)-乙腈(40∶60,v/v),20%磷酸调节pH为5.0;λ_(ex)=255nm,λ_(em)=390nm;流速1.0mL·min^(-1),柱温为25℃。结果:替米沙坦在6.25-3200ng·mL^(-1)的范围内有良好的线性关系(r=0.9998),最低检测浓度为1.25ng·mL^(-1)(S/N>3),该方法的相对回收率为99.7%-102.3%(n=5);绝对回收率为96.7%-105.3%(n=5);日内 RSD 为2.0%-5.9%,日间 RSD 为1.1%-6.2%。结论:本方法简便,准确,灵敏,特异性强,重现性好,可用于血浆中替米沙坦的测定及人体内药代动力学研究。

Synthesis of N-Succinyl-chitosan(Suc-Chi) and Preparation of Oxymatrine(OM)/N-Succinyl-chitosannanoparticles

Oxymatrine （OM）/N-succinyl-chitosan （Suc-Chi, with a degree of substitution being 0. 32） was synthesized via the ring-opening reaction of succinic anhydride with chitosan in dimethyl sulfoxide. OM-loaded Suc-Chi nanoparticles were prepared by an ionotropic gelation process and OM was quantified via the HPLC method： The influences of the initial OM concentration on the nanoparticle characteristics and OM release behavior were evaluated. The nanoparticles were found to have a mean diameter within a range of 267-392 nm, a positive surface charge, and a zeta potential in the range of 19-27 inV. The formulation with an initial OM concentration of 100μg/mL provided the highest loaded capacity（0. 77% ） and the highest extent of the released OM （68% at 24 h）, suggesting the possibility to achieve a therapeutic dose. According to the data obtained, this Suc-Chi-based nanotechnology will open up new and interesting prospects for the development of new anticancer drugs.

Oxymatrine Improves TNBS-induced Colitis in Rats by Inhibiting the Expression of NF-κB p65

Inflammatory bowel disease is thought to be regulated by the balance between Th1 and Th2 cytokines secreted by T cells, and NF-κB p65 also plays a predominant role in the intestinal inflammation. We evaluated the potency of oxymatrine, one of active components of Sophora Root, in inhibiting the immune responses and inflammation in 2,4,6-trinitrobenzene sulfonic acid （TNBS）-induced colitis. The inflammation was markedly ameliorated in the oxymatrine-treated rats. The level of IL-2 was increased and that of IL-10 was decreased in colon tissue in the rat model, which was reversed by the treatment of oxymatrine. Moreover, the elevated expression of NF-κB p65 in colon tissue in the model was also improved by oxymatrine treatment. Our results suggest that oxymatrine might be beneficial for the abnormal immune responses and inflammation by regulating the unbalance of Th1 and Th2 cytokines secretion and inhibiting the expression of NF-κB p65 in colon tissue.

Antifungal activities of matrine and oxymatrine and their synergetic effects with chlorthalonil

The EC50 values of matrine and oxymatrine against five forest pathogenic fungi （Fusarium oxysporum, Valsa pini, Cladosporium oxysporum, Sphaeropsis sapinea, Marssonina brunnea） were examined by bioassay methods. The results demonstrated that matrine and oxymatrine had strong inhibitory activities to the conidium germination of the tested fungi. The ECso values of matrine for inhibiting the conidium germination of Marssonina brunnea, Cladosporium oxysporum, Sphaeropsis sapinea were 123μg·mL^-1, 272 μg·mL^-1, 1133 μg·mL^-1, respectively, and the EC50 values of oxymatrine for inhibiting the conidium germination of Fusarium oxysporum, Sphaeropsis sapinea were 532μg·mL^-1, 601μg·mL^-1, respectively. The hyphal growth of the fungi was also significantly inhibited by matrine and oxymatrine. The ECs0 values of matrine inhibiting the conidium germination of Sphaeropsis sapinea, Valsa pini, Fusarium oxysporum were 428μg·mL^-1, 535 μg·mL^-1, 592 μg·mL^-1, respectively. The EC50 values of oxymatrine inhibiting the conidium germination of Valsa pini, Fusarium oxysporum were 323, 618μg·mL^-1, respectively. In the synergetic tests the ECs0 values of the mixtures of thiophanate methyl （or chlorthalonil） and matrine （or oxymatrine） were lower than 34 μg·mL^-1 while their co-toxicity coefficients were significantly higher than 1130 It indicated that the mixture of the alkaloids and the chemical had potential practical utilization in controlling certain forest fungal diseases.

Inhibition of hepatitis B virus by oxymatrine in vivo

AIM To investigate the anti-HBV effect ofoxymatrine (oxy) in vivo.METHODS HBV transgenic mice were producedby micro-injection of a 4.2kb fragmentcontaining the complete HBV genomes.Expression level of HBsAg and HBcAg in thetransgenic mice liver was determined byimmunohistochemical assay.RESULTS Four groups (6 mice in each group)were injected intraperitoneally with oxy at thedosage of 100,200, and 300 mg/kg or with salineonce a day for 30 days. Both HBsAg and HBcAgwere positive in livers of all the six mice in thecontrol group (injected with saline), and werepositive in livers of two mice in 100 mg/kg groupand 300mg/kg group. In 200mg/kg group,HBsAg and HBcAg were negative in livers of allthe six mice. Based on the results, 200 mg/kg isthe ideal dosage to explore the effect of oxy atdifferent time points. According to the oxytreatment time, mice were divided into fourgroups: 10 d, 20 d, 30 d and 60 d (4 mice in eachgroup). Each mouse underwent liver biopsy twoweeks before the treatment of oxy. Down-regulation of HBsAg and HBcAg appeared aftertreatment of oxymatrine for 10 d and 20 d, Dane-like particles disappeared after the treatment ofoxy for 20d under electron microscopy,however, the expression level of HBsAg andHBcAg returned to normal 60 d later after oxytreatment.CONCLUSION oxymatrine can reduce thecontents of HBsAg and HBcAg in transgenic miceliver, longer treatment time and larger dosagedo not yield better effects.

不同因子胁迫盐藻积累 β-胡萝卜素异构体的 HPLC 动态规律分析

本文采用ＨＰＬＣ技术研究了光强、温度、盐度三因子对盐藻积累β－胡萝卜素的动态协同胁迫作用．结果表明：它们存在着很强的协同胁迫作用，在温度２５℃，自然光照射时，２４０‰盐度积累β－胡萝卜素量大于１８０‰（０．７１６μｇ／ｍｌ＞０．３３７μｇ／ｍｌ），但在３２℃，光强１００００ｌｘ时，１８０‰盐度积累量大于２４０‰（（２．９４８μｇ／ｍｌ＞０．９８８μｇ／ｍｌ）；这一动态过程的时间曲线为“抛物”曲线；强胁迫条件有利于全反式异构体积累。

Effect of oxymatrine on interferon-gamma and tumor necrosis factor-alpha serum levels in an experimental rat model of autoimmune encephalomyelitis

BACKGROUND： Studies have demonstrated that experimental autoimmune encephalomyelitis （EAE） onset correlates with increased interferon-v （IFN-γ） and tumor necrosis factor-α （TNF-α） expression. Oxymatrine （OM） has been shown to inhibit autoimmune responses, but there are no reports showing that it could prevent the development of EAE. OBJECTIVE： To observe the effect of OM on serum levels of IFN-γ and TNF-α in a rat model of EAE.DESIGN, TIME AND SETTING： A randomized, controlled, animal study was performed at the Experimental Animal Center of Henan Academy of Chinese Medicine and at the Key Disciplines Laboratory Clinical Medicine of Henan Province between July and December 2008. MATERIALS： OM was purchased from Chia-tai Tianqing Pharmaceutical, China; complete Freund＇s adjuvant was purchased from Sigma, USA. METHODS： Forty female Wistar rats were randomly assigned to four groups： EAE model （M）, low-dose OM treatment （OM-L）, high-dose OM treatment （OM-H）, and normal control （N, no immunization）, with 10 rats in each group. EAE was established in the M, OM-L, and OM-H groups following immunization with Guinea pig spinal cord homogenate and complete Freund＇s adjuvant. The M and N groups were intraperitoneally injected with normal saline （6.7 mL/kg per day）, the OM-L group received an intraperitoneal injection of OM （100 mg/kg per day）, and the OM-H group received OM （150 mg/kg per day）. MAIN OUTCOME MEASURES： At 16 days after immunization, the degree of histopathological changes in the spinal cord was assessed by hematoxylin-eosin stanining. Enzyme-linked immunosorbent assay was used to detect serum levels of IFN-γ, and radioimmunoassay was utilized to determine serum TNF-α level. Neurological scores were measured on a daily basis according to a 0-5 scale. RESULTS： Daily injections of OM, both high and low doses, resulted in decreased neurological scores in EAE rats （P〈0.01）, as well as reduced cellular infiltration in the spinal cord and decreased levels of serum IFN-γ and TNF-α （P〈 0.01）. CONCLUSION： OM reduced the onset and severity of EAE, which correlated with decreased IFN-γ and TNF-α expression.

Ion-pairing HPLC methods to determine EDTA and DTPA in small molecule and biological pharmaceutical formulations

Ion-pairing high-performance liquid chromatography-ultraviolet （HPLC-UV） methods were developed to determine two commonly used chelating agents, ethylenediaminetetraacetic acid （EDTA） in Abilify （a small molecule drug with aripiprazole as the active pharmaceutical ingredient） oral solution and die- thylenetriaminepentaacetic acid （DTPA） in Yervoy （a monoclonal antibody drug with ipilimumab as the active pharmaceutical ingredient） intravenous formulation. Since the analytes, EDTA and DTPA, do not contain chromophores, transition metal ions （Cu2＋, Fe3＋） which generate highly stable metallocom- plexes with the chelating agents were added into the sample preparation to enhance UV detection. The use of metallocomplexes with ion-pairing chromatography provides the ability to achieve the desired sensitivity and selectivity in the development of the method. Specifically, the sample preparation in- volving metallocomplex formation allowed sensitive UV detection. Copper was utilized for the de- termination of EDTA and iron was utilized for the determination of DTPA. In the case of EDTA, a gradient mobile phase separated the components of the formulation from the analyte. In the method for DTPA, the active drug substance, ipilimumab, was eluted in the void. In addition, the optimization of the concentration of the ion-pairing reagent was discussed as a means of enhancing the retention of the aminopolycarboxylic acids （APCAs） including EDTA and DTPA and the specificity of the method. The analytical method development was designed based on the chromatographic properties of the analytes, the nature of the sample matrix and the intended purpose of the method. Validation data were presented for the two methods. Finally, both methods were successfully utilized in determining the fate of the chelates.

Authentication of Cassia seeds on the basis of two-wavelength HPLC fingerprinting with the use of chemometrics

High performance liquid chromatographic(HPLC) fingerprints of Cassia seed,a traditional Chinese medicine(TCM),were developed by means of the chromatograms at two wavelengths of 238 and 282 nm.Then,the two data sets were combined into one matrix.The application of principal component analysis(PCA) for this data matrix showed that the samples were clustered into four groups in accordance with the plant sources and preparation procedures.Furthermore,partial least squares(PLS),back propagation artificial neural...