High-performance Liquid Chromatography Conditions Research Articles

Cross-Linking Biotechnology and Pharmaceutical Biochemistry Insights: Investigating Medicinal Potential in Azadirachta Indica, Swietenia Mahagoni and Melia Azedarach

Background: The increasing resistance to synthetic drugs and their side effects has prompted renewed interest in the medicinal potential of natural products. Azadirachta indica, Swietenia mahagoni, and Melia azedarach, members of the Meliaceae family, have been traditionally used for their diverse therapeutic properties. Their efficacy stems from a range of bioactive compounds known for antifungal, antiviral, antibacterial, and anti-inflammatory activities. Objective: This study aims to explore and quantify the bioactive compounds in Azadirachta indica, Swietenia mahagoni, and Melia azedarach, assess their therapeutic potentials, and discuss their implications for drug development and human healthcare. Methods: Plant materials were collected, and extracts were prepared using ethanol, methanol, or water as solvents. Following maceration and filtration, the extracts were concentrated and analyzed using High-Performance Liquid Chromatography (HPLC). HPLC conditions were optimized for each plant, focusing on key compounds such as azadirachtin, nimbin, swietenine, meliacarpinin, and azedarachin. Method validation was performed to ensure precision, accuracy, and reproducibility. Results: The study identified high concentrations of bioactive compounds in each plant: Azadirachta indica contained azadirachtin (450 mg/g), nimbin (120 mg/g), and salannin (50 mg/g); Swietenia mahagoni had concentrations of swietenine (200 mg/g) and limonoids (180 mg/g total); Melia azedarach demonstrated high levels of meliacarpinin (300 mg/g) and azedarachin (220 mg/g). Conclusion: The confirmation of high levels of specific bioactive compounds in these plants supports their traditional uses and highlights their potential in developing new therapeutic agents that are environmentally sustainable and potentially more effective than current synthetic options. This research underscores the importance of integrating traditional knowledge with modern scientific approaches in drug discovery.

Optimization of hydrolysis conditions of alginate based on high performance liquid chromatography

Alginate is the most abundant polysaccharide compound in brown algae, which is widely used in various fields. At present, the determination of the content of alginate is mostly carried out using sulfuric acid and trifluoroacetic acid hydrolysis followed by the determination of the content, but the results are not satisfactory, and there are problems such as low hydrolysis degree and low recovery rate. Therefore, in this study, based on the optimization of high performance liquid chromatographic conditions for pre-column derivatization of 1-phenyl-3-methyl-5-pyrazolone (PMP), the hydrolysis effects of sulfuric acid, trifluoroacetic acid (TFA), oxalic acid, and formic acid were compared and the hydrolysis conditions were optimized. The results showed that formic acid was the best hydrolyzing acid. The optimal hydrolysis conditions were 95 % formic acid at 110 °C for 10 h. The hydrolysis effect was stable, with high recovery and low destruction of monosaccharides, which made it possible to introduce formic acid into the subsequent polysaccharide hydrolysis. The pre-column derivatization high performance liquid chromatography method established in this study was accurate and reliable, and the hydrolysis acid with better effect was screened, which provided a theoretical basis for the subsequent determination of alginate content.

The Effect of Bacterial AHL on the Cyclic Adenosine Monophosphate Content in Plants According to High-Performance Liquid Chromatography.

Cyclic adenosine monophosphate (cAMP) is an important second messenger in cells, mediating various stimulation signals such as the growth and development of organisms and stress and participating in regulating various biological processes of cells. This article explores the quantitative determination of cAMP in plants using High-Performance Liquid Chromatography (HPLC) and applies this method to analyzing the changes in cAMP content during the process of plant response to the bacterial quorum sensing signal N-acyl homoserine lactone (AHL). Research has shown that the optimal detection conditions for HPLC are as follows: the chromatographic column is Venusil MP C18 (2), the mobile phase is methanol-water (0.1% trifluoroacetic acid) (v:v, 10:90), the detection wavelength is 259 nm, the column temperature is 35 °C, and the flow rate is 0.8 mL/min. The precision of the standard sample of this method is 98.21%, the precision of the sample is 98.87%, and the recovery rate is 101.067%. The optimal extraction conditions for cAMP in Arabidopsis are to use 15% methanol ultrasonic extraction for 10 min, followed by a 40 °C water bath for 4 h. Bacterial AHL signal processing can significantly stimulate an increase in cAMP levels in Arabidopsis leaves and roots. The establishment of HPLC detection methods for the cAMP content in plants is of great significance for in-depth research on the signal transduction mechanisms of plant-bacterial interactions.

Advances in High-Performance Liquid Chromatography (HPLC) Method Development and Validation: A Comprehensive Review

High-Performance Liquid Chromatography (HPLC) stands as the cornerstone technique for the detection, separation, and quantification of drugs in various matrices. Method optimization necessitates a thorough investigation of multiple chromatographic parameters, encompassing sample pretreatment, mobile phase composition, column selection, and detector configuration. This article aims to comprehensively address the processes of method development, optimization, and validation within the realm of HPLC. The inherent advantages of HPLC, including its rapidity, specificity, accuracy, precision, and automation feasibility, render it an indispensable tool for analyzing a wide spectrum of drugs in complex multi-component dosage forms. Furthermore, HPLC method development and validation hold paramount importance across the spectrum of drug discovery, development, and manufacturing, as well as in diverse human and animal studies. The validation of analytical methods during drug development and manufacturing is imperative to ensure their fitness for the intended purpose. Adhering to Good Manufacturing Practice (GMP) requirements, pharmaceutical industries must establish comprehensive validation policies outlining the validation procedures. This article primarily delves into the optimization of HPLC conditions, emphasizing the critical role of method refinement in ensuring robust and reliable analytical methods.

Beyond Use Date (BUD) Determination of Ambroxol Hydrochloride Syrup by High-Performance Liquid Chromatography – UV/VIS Detector

Ambroxol HCl is a mucolytic agent often used to treat respiratory disorders associated with excess mucus secretion. This study aims to determine the beyond-use date (BUD) of ambroxol HCl syrup on the market based on analysis of the decrease in drug content using High-Performance Liquid Chromatography (HPLC) – UV/Vis detector. The HPLC conditions were reversed-phase with a C18 column, mobile phase containing acetonitrile - phosphate buffer 0.05 M pH 4.5 (60:40) at a flow rate of 1.0 ml/min using UV detection at 248 nm. To determine BUD, five syrup preparations (brands) obtained from the Jakarta area were analyzed in triplicate. The retention time for ambroxol HCl was 4.62 minutes. In the validation, ambroxol HCl showed good linearity with r = 0.99985 in the 6 to 36 µg/ml. LOD and LOQ for ambroxol HCl were 0.74 µg/ml and 2.25 µg/ml, respectively. It is also fulfilled the accuracy and precision parameters with a % recovery from 99.04% to 100.94% and CV<2%. This method meets the requirements according to the ICH Q2(R1) guidelines and can be used for the assay of ambroxol HCl syrup. The ambroxol HCl level on all samples was still higher than 90% (until the 36th day). Normality test data result indicated that data must be divided into two groups that are sample A and B, and sample C, D, and E. In conclusion, the extrapolation result showed that the BUD ambroxol HCl syrup was 83 days for sample A and B, and 49 days for sample C, D, and E.

Assay of amino acids in leaves of Eucommia ulmoides under arbor forest mode and leaf-oriented cultivation mode by pre-column derivatization HPLC

This study aims to develop the pre-column derivatization high performance liquid chromatography(HPLC) method for the determination of 16 kinds of amino acids in Eucommia ulmoides leaves, and compare the content of amino acids in the leaves harvested at different time and under leaf-oriented cultivation mode(LCM) and arbor forest mode(AFM). The HPLC conditions are as below: phenyl isothiocyanate(PITC) as pre-column derivatization agent, Agilent ZORBAX C_(18 )column(4.6 mm×250 mm, 5 μm), mobile phase A of acetonitrile-water(80∶20), mobile phase B of 0.1 mol·L~(-1) sodium acetate solution-acetonitrile(94∶6), gradient elution, flow rate of 1.0 mL·min~(-1), injection volume of 5 μL, column temperature of 40 ℃, and detection wavelength of 254 nm. The HPLC profile indicated well separation of 16 kinds of amino acids and the amino acid content in E. ulmoides leaves was up to 16.26%. In addition, the amino acid content in leaves of E. ulmoides under LCM was higher than under AFM. The amino acid content varied with the harvesting time. Through orthogonal partial least squares discriminant analysis, the amino acids of E. ulmoides under LCM and AFM were compared, which can distinguish the leaves under LCM from those under AFM. Principal component analysis was applied to comprehensively score the amino acids of E. ulmoides leaves. The results showed that the score of leaves under LCM was higher than that under AFM. Nutritional evaluation results indicated that the proteins in E. ulmoides leaves belonged to high-quality vegetable proteins. The established method for the determination of amino acid content is reliable. With the amino acid content as index, the leaf quality of E. ulmoides under LCM is better than that under AFM. This study lays a theoretical basis for the promotion of LCM for E. ulmoides and the development of medicinal and edible products from E. ulmoides leaves.

Selective determination of formaldehyde by high-performance liquid chromatography with porous graphitic carbon column using N,N′-bis(9-anthrylmethyl)propane-1,3-diamine as derivatizing reagent

Aromatic compounds containing two secondary amino groups were designed and prepared as new derivatizing reagents for aldehydes. One of them, N,N'-bis(9-anthrylmethyl)propane-1,3-diamine (APD), could achieve selective determination of formaldehyde (FA) on a porous graphitic carbon (PGC) column using xylenes, chlorobenzene, and 1-chloronaphthalene as mobile phases by high-performance liquid chromatography (HPLC). The APD-FA derivative was eluted from the PGC column, while the other APD-aldehyde derivatives remained on the column during the HPLC measurements. This specific elution was not observed using mobile phases such as acetonitrile, 1,4-dioxane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, chloroform, benzene, toluene, benzyl alcohol, 2-ethyl-1-hexanol, and pyridine. The APD-FA derivative had a six-membered ring of two tertiary amines identified using 1H NMR spectroscopy. When the π-π interaction of the solvent molecule of the mobile phase with PGC overcame that between the APD-FA derivative and PGC, the APD-FA derivative could be eluted from the column. The best resolution between the peak of the APD-FA derivative and that of free APD was observed when using o-xylene. The optimum derivatization and the HPLC conditions for selective HPLC determination of FA were to conduct the derivatization of FA by heating in an aqueous phase with APD in o-xylene at 100°C. In this method, FA could be derivatized with APD at a mildly neutral pH of 6.7, unlike the low pH required for the derivatization of aldehydes with 2,4-dinitrophenylhydrazine (DNPH), which is commonly used for the derivatization of aldehydes. The detection and quantification limits of FA were 0.8 and 3.5ngmL-1 in this HPLC method with fluorescent detection, respectively. This selective HPLC method could be applied to the determination of FA in various water samples. It was found that only APD among the derivatizing reagents containing two secondary diamines was useful for the selective determination of FA.

Detection of four biogenic amines by liquid chromatography based on aptamer signal replacement combined with cyclic amplification

Biogenic amines (BAs) represent a class of potentially harmful substances in foods and medicines. Their content is thus an important indicator of proper hygiene in food preparation, and purity of medicines. It is of great practical significance to establish accurate and sensitive detection of BAs in food and drugs. In this study, a high performance liquid chromatography (HPLC) method was developed for the simultaneous detection of multiple BAs in fish, pork and antibiotics based on aptamer signal replacement and cyclic amplification strategy. First, non-fluorescent targets were converted into fluorescent nucleic acid probes using a two-step replacement process. Subsequently, a large number of nucleic acid probes with different lengths and base sequences were generated using a double-stranded specific nuclease-assisted signal amplification strategy. Finally, various BAs in real samples were accurately identified using an HPLC platform. The influence of base sequence and nucleic acid probe length on separation via HPLC was studied to improve discrimination among fluorescent signals. Four different sequences were selected as tails to the DNA probe, and their retention times increased in turn. Experimental conditions, including column temperature, flow rate, gradient elution process, reaction temperature, and incubation time, were optimized by orthogonal experiments to further improve signal separation efficiency. Specifically, the methanol gradient was changed from 10% to 20% during 0-20 min, 35 ℃ of column temperature and 1.0 mL/min of flow rate were chosen as the HPLC conditions. The final resolution of chromatographic peaks was 3.44, 3.59 and 2.37, indicating complete separation between peaks. Optimal incubation time for BA capture by aptamer was 120 min, and optimal dosage of duplex specific nuclease (DSN) and Mg2+were 0.9 U and 30 mmol/L. The optimal pH, incubation temperature, and DSN incubation time were 7.0, 40 ℃ and 210 min, respectively. The proposed method exhibited high sensitivity towards BAs, with a linear range of 1 pmol/L-1 μmol/L, and the limits of detection of tyramine, histamine, spermine, and tryptamine were 0.25, 0.21, 0.27 and 0.19 pmol/L, respectively. The feasibility of this method was verified, and contrast experiments indicated that it could achieve highly selective detection of four BAs in one run. The applicability of this integrated method was also investigated for the detection of real samples (gentamycin sulfate, fish and pork). To assess the matrix effect, each BA with different concentrations were spiked into real fish and pork samples. Relative recoveries and relative standard deviations (RSDs) ranged from 101.2% to 104.5% and from 1.5% to 4.3%, respectively. The above detection results for real samples showed that this method could accurately capture, separate, and identify BAs in complex matrix samples. This strategy can effectively improve analyte selectivity and reduce the matrix effect. This assay is thus expected to provide a new approach for food and drug analyses.

Development of an HPLC method for asperulosidic acid quantification in the powder prepared from the spinal degeneration remedy of physician Nguyen Thien Chung

Nguyen Thien Chung’s remedy which consists of 13 medicinal herbs had been demonstrated its analgesic and anti-inflammatory effects on animal experiments. This remedy has further been developed into powder form. This study was conducted to develop a method to quantify asperulosidic acid, the important marker in BT powder, by high-performance liquid chromatography (HPLC). Sample processing conditions and quantitative HPLC conditions were screened. The HPLC method was validated according to the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines for system suitability, specificity, linearity, precision and accuracy. Methanol was chosen as the solvent for sample preparation and the ratio between BT powder and methanol was 300:25 (mg/ml). The selected HPLC conditions included a C18 Shimpack GIST column (250×4.6 mm, 5 μm), a detection wavelength of 236 nm, a column temperature of 30oC, a flow rate of 1 ml/min, and an injection volume of 10 μl. The mobile phase was a mixture of acetonitrile and 0.1% H3PO4 with a ratio of 9.5:90.5 (v/v). The quantitative method showed a good linear correlation between the peak area and the concentration of asperulosidic acid (r2=0.9987). The Relative standard deviation (RSD) value of the intermediate precision was 1.24%. The recovery was found in a range of 91.22-99.76%. The HPLC method for asperulosidic acid quantification in BT powder met the validation requirements and could be applied to standardise and evaluate the quality of BT powder.

Rapid determination of the total content of oleanolic acid and ursolic acid in Chaenomelis Fructus using near-infrared spectroscopy.

Chaenomelis Fructus is a widely used traditional Chinese medicine with a long history in China. The total content of oleanolic acid (OA) and ursolic acid (UA) is taken as an important quality marker of Chaenomelis Fructus. In this study, quantitative models for the prediction total content of OA and UA in Chaenomelis Fructus were explored based on near-infrared spectroscopy (NIRS). The content of OA and UA in each sample was determined using high-performance liquid chromatography (HPLC), and the data was used as a reference. In the partial least squares (PLS) model, both leave one out cross validation (LOOCV) of the calibration set and external validation of the validation set were used to screen spectrum preprocessing methods, and finally the multiplicative scatter correction (MSC) was chosen as the optimal pretreatment method. The modeling spectrum bands and ranks were optimized using PLS regression, and the characteristic spectrum range was determined as 7,500–4,250 cm−1, with 14 optimal ranks. In the back propagation artificial neural network (BP-ANN) model, the scoring data of 14 ranks obtained from PLS regression analysis were taken as input variables, and the total content of OA and UA reference values were taken as output values. The number of hidden layer nodes of BP-ANN was screened by full-cross validation (Full-CV) of the calibration set and external validation of the validation set. The result shows that both PLS model and PLS-BP-ANN model have strong prediction ability. In order to evaluate and compare the performance and prediction ability of models, the total content of OA and UA in each sample of the test set were detected under the same HPLC conditions, the NIRS data of the test set were input, respectively, to the optimized PLS model and PLS-BP-ANN model. By comparing the root-mean-square error (RMSEP) and determination coefficient (R2) of the test set and ratio of performance to deviation (RPD), the PLS-BP-ANN model was found to have better performance with RMSEP of 0.59 mg·g−1, R2 of 95.10%, RPD of 4.53 and bias of 0.0387 mg·g−1. The results indicated that NIRS can be used for the rapid quality control of Chaenomelis Fructus.

Determination of 32 oxidative dyes by high performance liquid chromatography and confirmation by high performance liquid chromatography-tandem mass spectrometry

染发类产品中氧化型染料种类多,实际样品测定时干扰多,建立染发类产品中多种常用染料的测定方法,为该类产品的有效监管提供技术手段十分必要。该研究根据染料使用频率分组,采用能够屏蔽硅羟基和金属离子影响的C18柱,优化了《化妆品安全技术规范》(2015年版)中32种染料的高效液相色谱法(HPLC)并建立了高效液相色谱-串联质谱(HPLC-MS/MS)确证方法。样品以10 g/L亚硫酸氢钠水溶液为抗氧化剂,用无水乙醇-水(1∶1, v/v)混合溶液冰浴超声提取10 min。HPLC方法采用甲醇、乙腈和磷酸盐缓冲液为流动相分两个液相色谱条件进行梯度洗脱分离,于280 nm波长下检测,其中一个HPLC条件中的相互干扰组分均在另一个HPLC条件下完全分离,避免了实际样品检测时组分间的干扰,并排除了32种以外的其他15种常用染料的干扰。HPLC-MS/MS方法分别采用5 mmol/L乙酸铵水溶液-乙腈和5 mmol/L乙酸水溶液-乙腈为正离子和负离子模式下的流动相,电喷雾离子模式下用多反应监测(MRM)模式进行定性和定量分析。HPLC和HPLC-MS/MS两个方法中,日内精密度和48 h内稳定性的相对标准偏差(RSD)<10%,回收率为82.6%~114.9%(RSD<10%)。HPLC方法中32种染料在大约10~500 mg/L范围内线性关系良好(r2>0.99),检出限为9.7~40.1 μg/g; HPLC-MS/MS方法中氢醌线性范围为2.0~79.7 mg/L,检出限为8.0 μg/g,其他组分线性范围约为0.1~4 mg/L,检出限为0.01~0.4 μg/g。采用HPLC、HPLC-MS/MS两个方法和《化妆品安全技术规范》方法同时测定实际样品,共检出16种染料,检出含量范围为58~25160 μg/g。3个方法检测结果的RSD为1.9%~10.1%。该研究增加了HPLC-MS/MS确证方法,适应化妆品法定检验中的未知物确认程序;方法简便快速,结果准确,专属性强,具有较好的通用性和可操作性。

Effect of origin, tree age, and harvesting time on content of flavonoids and terpene lactones in Ginkgo Folium

The content of total flavonol glycosides in Ginkgo Folium in the planting bases was determined by high performance liquid chromatography(HPLC).The samples were extracted by reflux with methanol-25% hydrochloric acid.The HPLC conditions were as follows: Agilent ZORBAX SB-C_(18) column(4.6 mm×250 mm, 5 μm), isocratic elution with mobile phase of 0.4% phosphoric acid solution-methanol(45∶55), flow rate of 1 mL·min~(-1), column temperature of 30 ℃, detection wavelength of 360 nm, and injection vo-lume of 10 μL.A method for the determination of terpene lactones in Ginkgo Folium was established based on ultra-high performance liquid chromatograph-triple-quadrupole/linear ion-trap tandem mass spectrometry(UPLC-QTRAP-MS/MS).The UPLC conditions were as below: gradient elution with acetonitrile-0.1% formic acid, flow rate of 0.2 mL·min~(-1), column temperature of 30 ℃, sample chamber temperature of 10 ℃, and injection volume of 10 μL.The ESI~+and multiple reaction monitoring(MRM) were adopted for the MS.The above methods were used to determine the content of total flavonol glycosides and terpene lactones in 99 batches of Ginkgo Folium from 6 planting bases, and the results were statistically analyzed.The content of flavonoids and terpene lactones in Ginkgo Folium from different origins, from trees of different ages, harvested at different time, from trees of different genders, and processed with different methods was compared.The results showed that the content of total flavonol glucosides in 99 Ginkgo Folium samples ranged from 0.38% to 2.08%, and the total content of the four terpene lactones was in the range of 0.03%-0.87%.The method established in this study is simple and reliable, which can be used for the quantitative analysis of Ginkgo Folium.The research results lay a basis for the quality control of Ginkgo Folium.

Separation of budesonide enantiomers with amylose-tris-[(S)-1-phenylethyl carbamate] chiral stationary phase and determination of its contents in pharmaceutical preparations

22R-布地奈德的药物活性比22S-布地奈德的强2~3倍,开发布地奈德对映体拆分和定量分析方法,可为其药物研发及质量控制提供重要依据。目前,主要以反相C18固定相对布地奈德对映体进行拆分,而采用手性固定相对其进行拆分少有报道。通过考察固定相、流动相和柱温对布地奈德对映体拆分的影响,建立了基于直链淀粉-三[(S)-1-苯乙基氨基甲酸酯]手性固定相快速拆分和检测布地奈德对映体的高效液相色谱方法,其色谱条件如下:色谱柱为Chiralpak AS-RH色谱柱(150 mm×4.6 mm, 5.0 μm),流动相为乙腈-水(45:55, v/v),柱温40 ℃,流速1.0 mL/min,二极管阵列检测器(DAD),检测波长246 nm,进样量10 μL。在该色谱条件下,布地奈德的两个对映体得到较好拆分,22R-布地奈德和22S-布地奈德的保留时间分别6.40 min和7.77 min,分离度为4.64; 22R-布地奈德和22S-布地奈德分别在各自范围内线性关系良好,相关系数(R2)均为0.9999,检出限分别为0.05 μg/mL和0.07 μg/mL,定量限分别为0.16 μg/mL和0.20 μg/mL; 4个添加水平的样品加标回收率为102.63%~104.17%,相对标准偏差(RSD)为0.08%~0.57%(n=6)。将该方法应用于1批次4个吸入用布地奈德混悬液实际样品进行检测,22R-布地奈德和22S-布地奈德的含量分别为283.15~284.63 μg/mL和259.86~261.51 μg/mL。该方法操作简便,分析时间短,重复性好,准确度高,可用于布地奈德对映体的拆分及其制剂的质量控制。

The potency of HPLC-DAD and LC-MS/MS combined with ion chromatography for detection/purification of levulinic acid and bio-compounds from acid hydrolysis of OPEFB.

This work reports a new strategy for the detection and purification of levulinic acid (LA) and bio-compounds from the acid hydrolysis and enzymatic treatment of oil palm empty fruit bunch (OPEFB) through high-performance liquid chromatography (HPLC) techniques combined with ion/ligand chromatography. The detections of LA, biomass-saccharides, hydroxymethylfurfural (HMF), and furfural were successfully elucidated by optimizing the multiple reaction monitoring mode (MRM) and liquid chromatography conditions using a Pb2+ ligand exchange column in the liquid chromatography with tandem mass spectrometry (LC-MS/MS) approach. High-performance liquid chromatography with diode-array detection (HPLC-DAD) combined with an H+ ion exchange column also showed potency for detecting chromophoric compounds such as LA, HMF, furfural, and acid (by-products) but not biomass-saccharides. Both techniques showed acceptable validation in terms of linearity, limit of detection (LOD), limit of quantitation (LOQ), accuracy, precision, and stability in both quantitative and qualitative analysis. However, the LC-MS/MS approach showed higher sensitivity for detecting LA and HMF compared with HPLC-DAD. Samples comprised of cellobiose, glucose, HMF, and LA from the acid hydrolysis of cellulose to LA with a mineral acid, and the biocatalysis of cellulase and β-glucosidase catalyzed cellulose (from OPEFB) to glucose were successfully monitored through the LC-MS/MS approach. In addition, using the optimal HPLC conditions obtained from LC-MS/MS, the purification of LA from other substances obtained from the hydrolysis reaction of cellulose (5 g) was successfully demonstrated by HPLC-DAD equipped with a fraction collector combined with an H+ ion exchange column at gram-scale of 1 g LA with a purification rate of 0.63 g ml-1 min-1.

Development of a Validated Stability-Indicating HPLC Method for Vinpocetine in the Presence of Potential Impurities in Tablet Dosage Form by Multiresponse Optimization.

Vinpocetine has been prescribed for the treatment of ischemic brain diseases for many years. The drug, which has side effects such as headache, flushing, and decreased blood pressure, is not found in nature, but it can be synthesized by several approaches. A simple, rapid, selective, stability-indicating high-performance liquid chromatographic (HPLC) method was developed for the simultaneous estimation of vinpocetine and their potential impurities in a tablet formulation. Optimum HPLC conditions were tried to be determined by a statistical experimental design method. The proposed method was validated as per the ICH guidelines. Stress study was used to demonstrate the stability-indicating ability of the developed method in the quantification of vinpocetine and potential impurities within the same run. According to multiresponse optimization using the Derringer's desirability function, the mobile phase consisted of an acetonitrile-phosphate buffer (pH 6.0) in the ratio of 65:35 (v/v) at a flow rate of 1.7 mL/min. Significant degradations were observed for the drug product under acid hydrolysis and alkali hydrolysis. The new method showed reasonable detection and quantification limits with good selectivity, precision, linearity, and recovery. These validation results have shown that this method is suitable for quantitative determination of vinpocetine and its impurities in quality control laboratories. A reliable and rapid HPLC method optimized with response surface methodology and multiresponse optimization based on Derringer's desirability function was developed for the simultaneous analysis of vinpocetine and its impurities in a tablet formulation.

Development of a quantitative method for analyzing three imidazole dipeptides using high-performance liquid chromatography and its application for meat and fish

Imidazole dipeptides (IDPs) such as anserine, balenine, and carnosine are functional peptides that are expected to improve cognitive functions and have antioxidant properties. However, there are few methods to extract these three representative IDPs from foods with high-efficiency and analyze them simultaneously using simple, rapid, and accurate high-performance liquid chromatography (HPLC). In this study, an analysis method was developed based on the combination of an internal standard, an extraction reagent, and HPLC conditions for the quantification of IDPs. IDPs in foods were extracted using 8 % perchloric acid solution with 4-imidazoleacrylic acid added as an internal standard; the IDPs were then analyzed by isocratic elution using an amino column. IDPs in nine types of meat and fish were quantified. The recovery and the quantification ranges of IDPs on the established method were 97.4 %–103.3 % and 0.78 μM–200 μM, respectively. The results showed that the amounts of balenine, anserine, and carnosine were extremely high in whale, salmon, and pork, respectively. Interestingly, venison contained the three IDPs, and the ratio of anserine to carnosine (balenine:anserine:carnosine = 1:4:5) was similar, which differed in other animal meats. This method can be used effectively, particularly for the quantification of foods containing these three IDPs.

Determination of Vancomycin B and Vancomycin Impurities by Liquid Chromatography

The preferred test methods for control of product-related impurities in medicinal products are high-performance liquid chromatography (HPLC) with a fine sorbent, and ultra-performance liquid chromatography (UPLC), which allow for better chromatographic separation of active substances and related impurities, reduction of time costs, and saving of material resources. The aim of the study was to develop HPLC and UPLC test procedures and assess the chromatographic separation capacity and efficiency in order to improve determination of the main vancomycin component and related impurities. Materials and methods: vancomycin hydrochloride lyophilisate for oral solution and solution for injection, and vancomycin hydrochloride reference standard (USP RS) were used as test objects. Agilent 1290 Infinity liquid chromatography system, and Chromolith® Performance RP-18e, Kinetex C18, Nucleodur C18 Isis, Zorbax RRHD Eclipse Plus C18, and LiChrospher® RP-18 columns were used for the testing. Results: HPLC analysis using a Chromolith® column (100×4.6 mm) reduces the testing time by 10 minutes compared to the USP test procedure, and by 15 minutes compared to the British Pharmacopoeia procedure. The proposed test procedure requires less eluent and increases chromatographic separation efficiency. UPLC analysis using a Kinetex C18 column (50×4.6 mm, 2.6 μm) made it possible to reduce the testing time by two thirds compared to the British Pharmacopoeia procedure. The use of isocratic elution greatly simplified the testing. The testing time under the proposed chromatographic conditions was 10 minutes. Conclusions: the selected HPLC and UPLC test conditions made it possible to significantly reduce the time of testing, minimise the use of expensive reagents, and increase efficiency of chromatographic separation in the determination of vancomycin impurities and the main component Vancomycin B.

Comprehensive analysis of components in Chinese medicines derived from Apocynum venetum and Poacynum pictum in Xinjiang based on HPLC fingerprint and chemometrics

This study established high-performance liquid chromatography(HPLC) fingerprints of Chinese medicines derived from Apocynum venetum and Poacynum pictum in Xinjiang and explored their composition differences with the combination of content determination, similarity analysis, cluster analysis and principal component analysis. The HPLC conditions included Phenomenex Kinetex C_(18) column(4.6 mm ×100 mm, 2.6 μm), acetonitrile-0.01% trifluoroacetic acid aqueous solution as mobile phase, gradient elution, flow rate of 0.6 mL·min~(-1), detection wavelength of 281 nm and column temperature of 25 ℃. The content of chlorogenic acid, quercetin-3-O-sophoroside, rutin, hyperin, isoquercitrin, trifolin and astragalin was determined in 31 batches of medicinal materials, and fingerprint research and chemometric analysis were performed with Similarity Evaluation System for Chromatographic Fingerprint of Traditional Chinese Medicine(Version 2004 A) and SPSS 21.0. In the Chinese Pharmacopoeia 2020, the quality of Apocyni Veneti Folium is controlled by character identification, microscopic identification, thin layer chromatography identification and quantitative determination of hyperin. There were 21 common peaks of A. venetum and P. pictum in the HPLC fingerprints, 5 of which were identified as chlorogenic acid, hyperin, isoquercitrin, trifolin and astragalin, with their content also determined. Except for 3 batches of medicinal materials, the similarity of other 28 batches was higher than 0.83, indicating good similarity. Two categories were formed in the cluster analysis based on content determination, which showed that some differences existed in similarities between different regions of Xinjiang. The medicinal materials were ranked by quality with principal component analysis, and the results indicated that the top 15 all came from northern Xinjiang. The quality difference of A. venetum and P. pictum had a correlation with the place of origin. This study provides a reference for the analysis and evaluation of A. venetum and P. pictum from different habitats and the selection of introduction and cultivation areas.

High performance liquid chromatographic method for determination of active components in lithospermum oil and its application to process optimization of lithospermum oil prepared by supercritical fluid extraction

紫草提取制备成的紫草油能够预防及治疗婴儿尿布疹、皮肤溃烂、湿疹等多种皮肤疾患,临床应用非常广泛,超临界流体萃取是紫草有效成分提取的优选方法。该文建立了紫草油有效成分的高效液相色谱(HPLC)测定方法,并以紫草油所含的有效成分含量为评价指标,采用三因素三水平正交试验法对紫草超临界流体萃取制备过程中的几个重要因素(萃取压力、萃取温度和CO2流量)进行考察,确定了紫草超临界流体萃取的最佳工艺流程。所建立的HPLC方法如下:Diamonsil C18色谱柱(250 mm×4.6 mm, 5 μm),流动相为含0. 1%甲酸的乙腈-含5 mmol/L甲酸铵的0.1%甲酸水溶液(75:25, v/v),等度洗脱,流速为1 mL/min;进样量为15 μL;柱温为室温;二极管阵列检测器(PAD)检测波长为275 nm。该法可在30 min内同时测定紫草油中的有效成分紫草素、乙酰紫草素、β-乙酰氧基异戊酰阿卡宁、异丁酰紫草素、β,β-二甲基丙烯酰紫草素和2-甲基丁酰基紫草素的含量,方法精密度、准确度、重复性好。在萃取压力23 MPa、萃取温度40 ℃、CO2流量27 L/h这一优化工艺流程下得到的紫草油有效成分含量最高。所建立的HPLC-PAD法简便可行、准确可靠,可用于超临界流体萃取制备紫草油的工艺过程优化和质量控制,也可为紫草及其制剂的质量评价提供参考。优化后的工艺条件能够满足紫草油制备需求,也符合生产实际需求。

HPLC Method for Simultaneous Determination of Dextromethorphan Hydrobromide, Chlorpheniramine Maleate and Potassium Sorbate in Cough Syrup

The development and validation of an analytical method for the simultaneous determination of Dextromethorphan Hydrobromide, Chlorpheniramine Maleate, and Potassium Sorbate in cough syrup using the High-Performance Liquid Chromatography (HPLC) method have been conducted. The determination was carried out on the simulation sample consisting of three substances and prepared five different concentrations, with three replications for each concentration. The optimum HPLC conditions were obtained using the C18 column, with UV detection at 230 nm The mobile phase of acetonitrile & phosphate buffer pH 2.5 (containing sodium-heptane sulfonate as ion-pair), with a gradient elution system, at a 1 mL/minute, while the flow rate column temperature is set at 35oC. The results showed that the method has met the parameters set in the validation test with the recovery ranged from 98% - 102%, the precision test results (RSD) < 2%, and the linearity (r) ≥ 0.98. The method obtained is quite selective by confirmed identity with the maximum wavelength scanning of each analyte peak by PDA detector. The limit of detection (LoD) for Dextromethorphan-HBr, Chlorpheniramine maleate and Potassium sorbate were 3.13 µg/mL, 0.94 µg/mL and 0.12 µg/mL respectively and the limit of quantitation (LoQ) were 9.49 µg/mL, 2.85 µg/mL and 0.38 µg/mL respectively.