PHENOLIC ANTIOXIDANTS DETERMINATION IN FOOD ITEMS USING REVERSED-PHASE HPLC

The determination of synthetic phenolic antioxidants （SPAs） including propyl gallate （PG）, tertiary butyl hydroquinone （TI3HQ）, butylated hydroxyanisole （BHA） and butylated hydroxytoluene （BHT） in food items is reported using high performance liquid chromatography （HPLC）. A Cls column is used as the stationary phase, acetonltrile and water：Acetic acid （1%） is used as the mobile phase of gradient elution and the UV detec- tor is set at 280 nm. Under the above conditions, four antioxidents is completely separated within 8 rain. The limit of detection, linear range, and reproducibility of HPLC are evaluated. Isolation parameters of SPAs from different types of food items （cooking oil, margarine and butter, and cheese） are optimized. SPAs are extracted from food items through extraction with methanol/acetonitrile （1 ： 1, in volume）, vortex, ultrasonic treatment and precipitation in a freezer （2 h）. For cooking oil margarine, butter and cheese at 50 and 200 rag/L, recoveries of SPAs are 93.3%0--108.3% （PG）, 85.3~^--108.3~~ （TBHQ）, 96.7~^--101.2~/6 （BHA）, and 73.9^-- 94.6% （BHT）. The method is applied to the determination of SPAs in 38 food items （16 cooking oils, 8 mar- garine, 6 butter and 6 cheese samples）. The levels of SPAs in positive samples are all below the legal limits of China.

Reversed-Phase HPLC Analysis of Steviol Glycosides Isolated from Stevia rebaudiana Bertoni

High Performance Liquid Chromatography (HPLC) experiments have been performed on nine steviol glycosides namely rebaudioside A, steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside F, and dulcoside A isolated from the leaves of Stevia rebaudiana using Reversed-Phase (RP) column. Using RP-HPLC method, the individual retention times for nine naturally occurring ent-kaurane diterpene glycosides of S. rebaudiana reported in JECFA have been determined at four different temperatures: 20℃, 40℃, 60℃, and 79℃. Also, calculated the relative retention times of the eight steviol glycosides steviolbioside, stevioside, rubusoside, rebaudioside B, rebaudioside C, rebaudioside D, rebaudioside F, and dulcoside A against the major steviol glycoside rebaudioside A. HPLC results suggested that temperatures 40℃ and 60℃ would be ideal conditions for better separation of steviol glycosides.

Single-run reversed-phase HPLC method for determining sertraline content,enantiomeric purity,and related substances in drug substance and finished product

A direct enantio-,diastereo-,and chemo-selective high-performance liquid chromatographic method was developed for determining the content,enantiomeric purity,and related substances of the chiral antidepressant drug sertraline HCl in a single chromatographic run.The separation was achieved on a chiral stationary phase based on amylose tris(3-chloro-5-methylphenylcarbamate)under reversed-phase conditions.The method was optimized by evaluating the influence of the temperature and mobile phase composition on the retention and selectivity.The application of the single-run approach allowed to baseline resolve all investigated species in less than 15 min,without using buffers or tandem-coupled columns.The chromatographic method was validated according to the guidelines of the Official Medicines Control Laboratory and applied to control the content of sertraline HCl and related chiral substances in a generic antidepressant formulation.

A reversed-phase HPLC-UV assay for simultaneous analysis of EGCG and ECG of tea polyphenols in rat plasma

Objective To develop a simple and specific reversed-phase HPLC-UV method for simultaneous determination of(-)Epigallocatechin-3-gallate(EGCG)and(-)Epicatechin-3-gallate(ECG),the main active ingredients of tea polyphenols(TP),in rat plasma.Methods EGCG and ECG were eluted on a Kromasil C18 analytical column(150 mm×4.6 mm,5 μm)protected by a C18 pre-column(4.6 mm×20 mm,10 μm)with a linear gradient mobile phase composed of CH3CN(A)-0.1% citric acid(B),which was run from initial 14% A and 86% B to 20% A and 80% B at a flow rate of 1.0 mL·min-1 in 14 min,then changed to 14% A and 86% B at a gradient flow rate of 1.0-1.5 mL·min-1 during 14-18 min,and then maintained until 22 min at a gradient flow rate of 1.5-1.0 mL·min-1.The UV detector was set at 280 nm.Plasma samples(200 μL each)were prepared by liquid-liquid extraction procedure with double volumes of EtoAc and then evaporation of organic phase under N2 stream to dry,followed by reconstitution with 100 μL of 20% CH3CN aqueous solution.The peak area ratios of analytes to vanillin as internal standard vs concentration of analytes to construct calibration curves.Results The HPLC resulted in base-line separation of vanillin,EGCG,ECG and other components;there was no interference from blank plasma.The linear range was 0.5-300 μg·mL-1 for EGCG(r=0.9999)and 0.1-60 μg·mL-1 for ECG(r=0.9999).The intra-and inter-day precision(RSD)was better than 6.1% and 12.6%,respectively,and the average accuracy was between 86.25%-103.14%.The extraction recovery of EGCG and ECG was 79.80%-84.64% and 75.22%-91.39%,respectively.The plasma samples were stable for at least 30 days at-20 ℃ and 8 h at room temperature;EGCG,ECG and IS stock solutions 2 months at-20 ℃,and the EtoAc-extracted plasma samples 24 h at 4 ℃.Application of the method to the determination of EGCG and ECG in plasma of rats receiving iv 100 mg·kg-1 of TP showed that these 2 compounds pharmacokinetically behaved as the two-compartment model and first-order kinetics,with t1/2β 122.9 min and 59.2 min,Vd 7.96 L·kg-1 and 1.22 L·kg-1,CL 0.044 L·kg-1·min-1 and 0.015 L·kg-1·min-1 for EGCG and ECG,respectively.Conclusions The method developed in the present study is highly specific,precise,accurate,and suitable for the non-clinical pharmacokinetic study of the TP in rats.

Reversed-Phase-HPLC Assay Method for Simultaneous Estimation of Sorbitol, Sodium Lactate, and Sodium Chlorides in Pharmaceutical Formulations and Drug Solution for Infusion

A rapid, straightforward, sensitive, efficient, and cost-effective reverse-phase high-performance liquid chromatographic method was employed for the simultaneous determination of Sorbitol, Sodium Lactate, and Chlorides in a drug solution for infusion. Sorbitol, Sodium lactate, and Chloride are all officially recognized in the USP monograph. Assay methods are provided through various techniques, with titrations being ineffective for trace-level quantification. Alternatively, IC, AAS, and ICP-MS, though highly accurate, are costly and often unavailable to most testing facilities. When considering methods, it’s important to prioritize both quality control requirements and user-friendly techniques. A simple HPLC simultaneous method was developed for the quantification of Chlorides, Sorbitol, and Sodium Lactate with a shorter run time. The separation utilized a Shimpack SCR-102(H) ion exclusion analytical column (7.9 mm × 300 mm, 7 μm), with a flow rate of 0.6 mL per min. The column compartment temperature was maintained at 40°C, and the injection volume was set at 10 μL, with detection at 200 nm. All measurements were conducted in a 0.1% solution of phosphoric acid. The analytical curves demonstrated linearity (r > 0.9999) in the concentration range of 0.79 to 3.8 mg per mL for Sodium Lactate (SL), 0.16 to 0.79 mg per mL for Sodium Chloride (SC), and 1.5 to 7.2 mg per mL for Sorbitol. Validation of the developed method followed the guidelines of the International Conference on Harmonization (ICH Q2B) and USP. The method exhibited precision, robustness, accuracy, and selectivity. In accelerated stability testing over 6 months, no significant variations were observed in organoleptic analysis and pH. Consequently, the developed method is deemed suitable for routine quality control analyses, enabling the simultaneous determination of Sodium Lactate, Sodium Chloride, and Sorbitol in pharmaceutical formulations and infusions.

Comparison of reversed-phase enantioselective HPLC methods for determining the enantiomeric purity of (S)-omeprazole in the presence of its related substances

A simple analytical high-performance liquid chromatography （HPLC） method was applied for the en- antiomeric excess determination of esomeprazole （（S）-OME）, the enantiopure active ingredient con- tained in drug products, in the presence of its potential organic impurities A-E. The enantioselective separation was accomplished on the immobilized-type Chiralpak ID-3 chiral stationary phase （CSP） under reversed-phase conditions. The results were evaluated and compared with those obtained by the official enantioselective method of European Pharmacopoeia used as the reference for checking the enantiomeric excess of （S）-OME. It has been established that the use of the Chiralpak ID-3 CSP allows the determination of the enantiomeric purity of （S）-OME without any interference coming from its chiral and achiral related substances. The analytical procedure of the drug regulatory agencies based on the AGP CSP suffered instead from poor specificity due to overlap of the peaks pertinent to the achiral impurity A and the chiral impurity （R）-OME （impurity F）.

Computer-assisted retention prediction system in reversed-phase HPLC for O-ethyl O-aryl N-isopropyl phosphoramidothioates

A computer-assisted retention prediction system (RPS) of fifteen O-ethyl O-aryl N-iso- propyl phosphoramidothioates (1) in reversed-phase HPLC was investigated. The system is based on the use of four physicochemical parameters (hydrophobicity , electric effect σ, field effect F and steric effect ) which is closely related to the retention mechanism in reversed-phase HPLC. The system was evaluated by comparing the measured retention data with the predicted ones. The predicted values were consistent with the measured values within a relative error of 11.5%.

Optimization of the separation of a mixture of unknown composition by reversed-phase HPLC

A method is presented for the computer-assisted optimization of mobile phase selection for the separation of a synthetic intermediate of unknown composition by reversed- phase HPLC.The method is based on recognition of the order of the peaks by comparison of peak area ratio and followed by the BSOS-L(Binary Solvent Optimization System for HPLC)method.Excellent agreement was obtained between predicted data and experimental results.

Reversed-phase fused-core HPLC modeling of peptides

Different fused-core stationary phase chemistries（C18,Amide,Phenyl-hexyl and Peptide ES-C18） were used for the analysis of 21 structurally representative model peptides.In addition,the effects of the mobile phase composition（ACN or MeOH as organic modifier;formic acid or acetic acid,as acidifying component） on the column selectivity,peak shape and overall chromatographic performance were evaluated.The RP-amide column,combined with a formic acid-acetonitrile based gradient system,performed as best.A peptide reversed-phase retention model is proposed,consisting of 5 variables：log SumAA,log Sv,clog P,log nHDon and log nHAcc.Quantitative structure-retention relationship（QSRR） models were constructed for 16 different chromatographic systems.The accuracy of this peptide retention model was demonstrated by the comparison between predicted and experimentally obtained retention times,explaining on average 86% of the variability.Moreover,using an external set of 5 validation peptides,the predictive power of the model was also demonstrated.This peptide retention model includes the novel in-silico calculated amino acid descriptor,AA,which was calculated from log P,3D-MoRSE,RDF and WHIM descriptors.

HPLC同时测定甜高粱中10种黄酮类化合物含量及抗氧化活性对比研究

试验旨在建立同时测定甜高粱不同部位中10种黄酮类化合物含量的高效液相色谱(HPLC)检测方法,并对总黄酮提取物抗氧化能力进行评价。试验以甜高粱陇甜粱2号成熟期籽粒、茎秆及全株为研究对象制备总黄酮提取物,利用HPLC同时测定不同部位总黄酮提取物中的儿茶素、氯化芹菜定、花旗松素、芦丁、槲皮素、木犀草素、柚皮素、高北美圣草素、芹菜素及麦黄酮含量。结果显示,10种黄酮类化合物分别在各自线性范围内与色谱峰峰面积线性关系良好,R^(2)为0.9984~0.9999,平均加样回收率为95.0%~105.8%,RSD为1.03%~2.86%。抗氧化性测定结果表明,甜高粱不同部位总黄酮提取物对羟基自由基、超氧阴离子自由基、1,1-二苯基-2-三硝基苯肼(DPPH)自由基和2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS^(+))自由基均具有一定的清除能力,不同浓度下清除率均表现为籽粒>全株>茎秆;籽粒总黄酮提取物浓度为1.00 g/L时,籽粒总黄酮提取物对DPPH自由基的清除率高于VC和2,6-二叔丁基-4-甲基苯酚(BHT)。相关性分析结果表明,不同部位总黄酮提取物含量与不同自由基清除率及总还原能力(FRAP)均呈正相关。研究表明,该试验方法简便,结果准确性较高,可用于甜高粱中黄酮类化合物含量的测定;甜高粱不同部位总黄酮提取物具有抗氧化活性。

HPLC及LC-MS测定榛子中氯吡苯脲和多菌灵残留

本文采用高效液相色谱法(HPLC)和液相色谱-质谱法(LC-MS)对干果榛子中氯吡苯脲和多菌灵残留量进行含量测定.HPLC和LC-MS均使用C18色谱柱,含量测定采取等度洗脱,流动相:甲醇-水(55∶45,体积比);体积流量:1.0 mL·min-1;测定波长:260 nm;柱温:30℃.LC-MS采取电喷雾离子源,梯度洗脱,体积流量:0.6 mL·min-1,柱温:30℃.结果表明,榛子中氯吡苯脲与多菌灵存在残留,氯吡苯脲质量浓度在1.00~10.00μg·mL-1范围内线性关系良好,加样回收率在95.58%~100.58%;多菌灵质量浓度在1.005~15.075μg·mL-1范围内具有良好的线性关系,加样回收率在95.61%~104.39%.实验证明,HPLC与LC-MS相结合的方法具有操作简便、灵敏度高、检出限低等优点,能有效地检测到榛子样品中膨大剂氯吡苯脲及杀菌剂多菌灵的残留,并确定其残留量,线性关系和回收率结果均令人满意.根据被检测的8批样品中氯吡苯脲和多菌灵两项农药残留量推断,作为一般干果食用榛子是安全的.

引火汤冻干粉HPLC指纹图谱建立及8种成分含量测定

目的建立引火汤冻干粉HPLC指纹图谱,并测定地黄苷D、麦冬甲基黄烷酮A、毛蕊花糖苷、原儿茶酸、梓醇、五味子醇甲、五味子乙素、五味子甲素的含量。方法指纹图谱建立采用Supersil AQ18色谱柱(4.6 mm×250 mm,5μm);流动相乙腈-0.1%磷酸,梯度洗脱;体积流量1.0 mL/min;柱温30℃;检测波长230 nm。UPLC-MS/MS含量测定采用Alphasil VC-C_(18)色谱柱(2.1 mm×100 mm,2.5μm);流动相乙腈-0.1%甲酸,梯度洗脱;体积流量0.3 mL/min;柱温30℃;电喷雾离子源;正负离子扫描;多反应监测模式。结果10批冻干粉指纹图谱中有17个共有峰,相似度大于0.90,指认出毛蕊花糖苷、水晶兰苷、去乙酰车叶草苷酸、五味子醇甲。8种成分在各自范围内线性关系良好(R^(2)>0.9906),平均加样回收率98.7%~101.1%,RSD 2.0%~5.2%。结论指纹图谱结合含量测定能完整表征引火汤基准样品质量,从而为其关键化学属性质量评价提供参考。

HPLC法同时测定脑脉泰胶囊中12种成分的含量

目的建立HPLC法同时测定脑脉泰胶囊中3′-羟基葛根素、2-羟基红花黄色素A、葛根素、葛根素芹菜糖苷、3′-甲氧基葛根素、大豆苷、二苯乙烯苷、木犀草苷、染料木苷、木犀草素、丹酚酸B、迷迭香酸的含量。方法分析采用KromasilC_(18)色谱柱(250mm×4.6mm,5μm);流动相乙腈-水(含1.0g/L磷酸),梯度洗脱;体积流量0.8mL/min;柱温30℃;检测波长280nm。再进行聚类分析、主成分分析。结果12种成分在各自范围内线性关系良好(r>0.9990),平均加样回收率97.07%~98.30%,RSD0.86%~1.82%。10批样品聚为4类,4种主成分累积方差贡献率达86.262%。结论该方法简便稳定,可靠准确,可为脑脉泰胶囊的质量控制提供科学依据。

HPLC测定吗替麦考酚酯口服混悬剂(骁悉)中尼泊金甲酯含量

建立了一种测定吗替麦考酚酯口服混悬剂中尼泊金甲酯含量的方法。采用高效液相色谱法,色谱柱:YMC-Pack Pro C18(150 mm×4.6 nm,5μm);流动相:甲醇-1%乙酸水(60∶40);检测波长:254 nm;流速:0.7 mL·min^(-1);柱温:30℃;进样量:10μL。采用该法测定,专属性强,精密度好(RSD=1.16%,n=12),准确度高(平均加样回收率为99.35%,回收率RSD<2%),操作简单,适用吗替麦考酚酯混悬剂生产中尼泊金甲酯含量检测。该法测得的吗替麦考酚酯混悬液中尼泊金甲酯含量为3.18 mg·mL^(-1),占混悬剂质量的0.50%。

HPLC法同时测定驻春胶囊中4个成分的含量

目的:建立以高效液相色谱法(HPLC)同时测定驻春胶囊中异补骨脂素、补骨脂素、淫羊藿苷、蛇床子素含量的方法。方法:采用HPLC法,以异补骨脂素、补骨脂素、淫羊藿苷和蛇床子素作为指标成分,采用Agilent ZORBAX SB-C_(18)色谱柱(4.6 mm×250 mm,5μm);流动相为甲醇-水,梯度洗脱,体积流量为1.0 m·min^(-1);柱温为30℃,检测波长为254 nm,进样量为5μL。结果:异补骨脂素、补骨脂素、淫羊藿苷和蛇床子素质量浓度分别在0.0059~0.1770 mg/mL、0.0049~0.1470 mg/mL、0.0031~0.093 mg/mL和0.0048~0.1440 mg/mL范围内与峰面积呈良好的线性关系,其相关系数分别为0.9996、0.9995、0.9997和0.9995,平均加样回收率分别为101.45%、100.95%、100.46%和101.17%;RSD分别为2.19%、1.83%、1.71%和2.01%。结论:该分析方法适用于驻春胶囊中异补骨脂素、补骨脂素、淫羊藿苷和蛇床子素的含量测定。

HPLC法同时测定益肾泄浊合剂中5种成分的含量

目的建立HPLC法同时测定益肾泄浊合剂中没食子酸、莫诺苷、马钱苷、毛蕊异黄酮苷、大黄酸的含量。方法分析采用Agilent Eclipse XDB-C_(18)色谱柱(250 mm×4.6 mm,5μm);流动相0.1%磷酸-乙腈,梯度洗脱;体积流量1.0 mL/min;柱温30℃;检测波长254 nm。结果5种成分在各自范围内线性关系良好(r≥0.9996),平均加样回收率97.28%~101.93%,RSD 2.56%~2.84%。结论该方法准确可靠,可用于益肾泄浊合剂的质量控制。

HPLC法同时测定舒肝利胆丸中5种成分的含量

目的建立HPLC法同时测定舒肝利胆丸中甘草苷、橙皮苷、迷迭香酸、槲皮素、柴胡皂苷a的含量。方法分析采用Waters Symmetry Shield C_(18)色谱柱(4.6 mm×250 mm,5μm);流动相乙腈-0.1%磷酸,梯度洗脱;体积流量1.0 mL/min;柱温20℃;检测波长210、237、283、330、368 nm。结果甘草苷、橙皮苷、迷迭香酸、槲皮素、柴胡皂苷a在各自范围内线性关系良好(r>0.9995),平均加样回收率98.41%~102.42%,RSD 1.78~2.81%。结论该方法准确、稳定、快速,可用于舒肝利胆丸的质量控制。

HPLC与紫外-可见分光光度法对翻白草中黄酮类成分含量测定

目的 建立测定翻白草中黄酮类成分含量的最佳方法。方法 先建立高效液相色谱法(HPLC)测定翻白草中的4种黄酮类物质含量的方法,其中流动相为乙腈与0.1%甲酸溶液,并采用梯度洗脱,柱温设为30℃,色谱柱为InertSustain C18(150 mm×4.6 mm, 5μm),检测波长设为360 nm,并对不同批次的翻白草中的4种黄酮类物质含量进行检测;选取芦丁作为对照品,以UV-VIS法测定翻白草中总黄酮含量。结果 不同产地的翻白草含有的黄酮类成分含量差异较大,总黄酮含量的差异也较大,建立的HPLC法与紫外-可见分光光变法(UV-VIS)法具有很好地重复性,样品稳定性好,且仪器精密度高,两种检测方法相结合能很好的把控翻白草品质。结论 以UV-VIS法对翻白草中的总黄酮进行测定,并采用HPLC法测定翻白草中含有的槲皮苷、芦丁、山柰酚和槲皮素,方法较为简便,且有很好的重复性、稳定性,精密度高,能很好地控制翻白草的品质,并为临床研究及其药理活性研究提供依据。

不同产地巴戟天HPLC指纹图谱及化学模式识别研究

目的:利用HPLC指纹图谱及化学模式识别对巴戟天药材进行评价。方法:采用Shodex Asahipak NH2P-504E色谱柱(4.6 mm×250 mm,5μm),以乙腈-水为流动相梯度洗脱,使用蒸发光散射检测器(ELSD)。利用相似度评价、聚类分析和主成分分析等化学模式识别方法,对不同产地的巴戟天药材进行分析。结果:所建立的HPLC指纹图谱共识别了18个共有峰,经与对照品图谱比较,鉴定其中的4个共有峰分别为果糖、蔗糖、蔗果三糖和耐斯糖。6个产地巴戟天的相似度在0.861~0.995;经聚类分析和主成分分析,6个产地巴戟天共聚为3类。结论:本研究采用的巴戟天HPLC指纹图谱及化学模式识别技术可反映出不同产地的巴戟天样品的差异,可为巴戟天的质量控制提供参考。

HPLC法测定五种产地地龙中次黄嘌呤和肌苷的含量

目的:建立地龙中次黄嘌呤与肌苷含量的测定方法,测定五种产地地龙成分,为地龙成分的提取工艺研究、质量分析探索新型高效的研究方法。方法:建立HPLC高效液相色谱法测定分析方法。色谱柱Agilent extend C18色谱柱,4.6 mm×250 mm,粒径:5μm。流动相为甲醇-0.2%磷酸,波长选择254 nm,进样量选择20μL,柱温为30℃,使用梯度洗脱法,建立次黄嘌呤和肌苷的标准曲线,进行精密度试验,稳定性试验,重复性试验,加样回收试验等方法学考察。结果:次黄嘌呤标准曲线:y=78.819x+245.92,R2=0.9999,在10.08~161.28μg·mL^(-1)范围内呈良好线性关系;肌苷标准曲线:y=56.566x+68.333,R2=0.9995,在20.08~321.28μg·mL^(-1)范围内呈良好线性关系。实验精密度、稳定性、重复性良好,计算得到次黄嘌呤的平均回收率为95.43%,RSD值为1.52%(n=6);肌苷的平均回收率为99.86%,RSD值为2.36%(n=6),广东、河南、海南、上海、广西五种产地地龙的次黄嘌呤含量分别为:0.5335、0.3468、0.6874、0.5694、0.7945 mg·g^(-1);肌苷含量为:1.5625、0.5674、1.1267、0.8436、1.2849 mg·g^(-1)。结论:建立的HPLC高效液相色谱法,梯度洗脱效果较好,实验准确度良好,精密度良好,稳定性良好,重复性高,是一种高效的分析测定方法。