固相萃取-高效液相色谱法测定水中残留嘧菌酯

目的建立固相萃取-高效液相色谱法分析测定水中残留甲氧丙烯酸酯类抗菌剂嘧菌酯的含量。方法样品经过固相萃取小柱净化富集后,采用Inertsil ODS-3色谱柱,乙腈-水（60∶40）为流动相,在250 nm紫外检测波长下进行高效液相色谱分析。结果嘧菌酯在0.01~1.0 mg.L-1范围内呈现良好线性（r=0.9992）。在低、中、高三个添加水平,嘧菌酯的回收率为91.5%~105.2%,相对标准偏差3.7%~8.2%。结论本法操作简便快速,可作为水中嘧菌酯含量监测的控制方法。     

Development and validation of reversed phase high performance liquid chromatography method for determination of dexpanthenol in pharmaceutical formulations

This paper describes the validation of an isocratic HPLC method for the assay of dexpanthenol in aerosol and gel. The method employs the Vydac Proteins C4 column with a mobile phase of aqueous solution of trifluoroacetic acid and UV detection at 206 nm. A linear response (r>0.9999) was observed in the range of 13.0-130 microg mL(-1). The method shows good recoveries and intra and inter-day relative standard deviations were less than 1.0%. Validation parameters as specificity, accuracy and robustness were also determined. The method can be used for dexpanthenol assay of panthenol aerosol and gel with dexpanthenol as the method separates dexpanthenol from aerosol or gel excipients.     

Determination of bopindolol using the flow injection technique coupled with solid phase extraction

In the proposed procedure, the determination of bopindolol using a flow injection analysis (FIA) technique, with spectrophotometric detection at 635 nm, is described. The method is based on the production of a green, water-soluble complex with ferric ions in acid medium. The automated lab-made FIA system was used for the direct determination of bopindolol in tablets. Bopindolol was adsorbed onto the solid phase in a mini-column, which was integrated directly into the flow system. The positive feature of the use of solid phase extraction (SPE) was the pre-concentration of bopindolol (seven times). The sample throughput was 50 samples per hour. Using the SPE method, bopindolol was determined with a linear range from 125 to 1000 μg ml⁻¹ (Relative standard deviation (R.S.D.)=1.87%), with a detection limit (3σ) of 70 μg ml⁻¹. The method was applied to the determination of bopindolol in Sandonorm® tablets. The results obtained were compared with a conventional HPLC method, both analytical techniques were in good agreement.     

Development and validation of a new HPLC analytical method for the determination of alprazolam in tablets

A new analytical method is developed together with its latter validation study, by means of a high resolution liquid chromatography (HPLC) of reverse phase to quantify alprazolam (8-chloro-1-methyl-6-phenyl-4H-[1,2,4] triazole [4,3,-]-[1,4] benzodiazepine) in tablets. Determination is carried out by means of an ODS C18 column (200 mm×4.6 mm i.d., 5 μm particle size); the mobile phase consisted of a mixture of 0.02 M buffer solution of phosphates (pH 6.0) and acetonitrile (45:55, v/v). It is pumped through the chromatographic system at a flow rate of 0.50 ml min⁻¹. The UV detector is operated at 254 nm. The validation study is carried out fulfilling the ICH guidelines in order to prove that the new analytical method, meets the reliability characteristics, and these characteristics show the capacity of an analytical method to keep, throughout the time, the fundamental criteria for validation: selectivity, linearity, precision, accuracy and sensitivity. The method is applied during the working day for the quality control of commercial alprazolam tablets in order to quantify the drug and its degradation products and to check the content uniformity test.     

Identification of in vitro phase I metabolites of benzotriazole UV stabilizer UV-327 using HPLC coupled with mass spectrometry

The benzotriazole UV stabilizer (BUVS) 2-(5-chloro-benzotriazol-2-yl)-4,6-di-(tert-butyl)phenol (UV-327) is used in various plastic products to protect them against harmful UV radiation. Meanwhile, there are concerns about potential adverse health effects on humans, as residues of UV-327 and other BUVSs have already been detected in various environmental matrices. However, information on the metabolism of UV-327 is not yet available. Therefore, in vitro experiments with human liver microsomes (HLMs) were performed in order to identify phase I metabolites to be used as specific biomarkers of exposure in biomonitoring studies. The samples were analyzed by HPLC coupled with mass spectrometry (HPLC/MS). Potential metabolites, which were formed by hydroxylation and further oxidation to carboxylic acid, were tentatively identified. Special metabolite structures were suspected and custom-synthesized as reference substances for verification. In total, seven phase I metabolites, which may be suitable biomarkers for the assessment of exposure to UV-327, have been identified and quantified. The results of the present study provide initial insights into the metabolic pathway of UV-327, which is essential for further research on its human metabolism.     

Determination of ephedrine alkaloids in Ephedra natural products using HPLC on a pentafluorophenylpropyl stationary phase

In this study a pentafluorophenylpropyl (PFPP) stationary phase was applied to the fast and reliable qualitative and quantitative analysis of ephedrine alkaloids in Ephedra plant material and derivatives. A Discovery HS F5 column (150mmx4.6mm i.d., 5microm) was used, with an isocratic mobile phase composed of ammonium acetate (7mM) in acetonitrile-water (90:10, v/v), at a flow rate of 1.0ml/min. The column temperature was set at 45 degrees C. UV detection was set at 215 and 225nm. The total analysis time was 16min. The validation parameters, such as linearity, sensitivity, accuracy, precision and specificity, were found to be highly satisfactory. Sonication and microwave extractions were compared in order to optimize the yield of the target analytes. Under the optimized extraction conditions (based on two cycles of sonication with methanol at 40 degrees C for 15min), different matrices containing Ephedra were successfully analyzed for their alkaloid content. The method was applied to the analysis of standard reference materials (SRMs) containing Ephedra. Furthermore, the developed technique allowed the simultaneous determination of ephedrine alkaloids and synephrine, the main phenethylamine alkaloid of Citrus aurantium, that has replaced Ephedra in dietary supplements used in the treatment of obesity. The results indicated that this procedure is suitable for the phytochemical analysis of Ephedra plant material and extracts, and can be applied to demonstrate the label claims for product content, including the absence of ephedrine alkaloids in Ephedra-free products.     

固相萃取-高效液相色谱法测定氯雷他定的血药浓度

目的:建立固相萃取-高效液相色谱法测定氯雷他定血药浓度的方法.方法:采用ODS-C18小柱处理样品,Zorbax SB-C18柱(4.6 mm× 250 mm,5μm),流动相:50mmol·L-1磷酸二氢铵缓冲液(磷酸调至pH 4.0)-乙腈(62:38),流速:1.2 mL·min-1,检测波长:275 nm.结果:线性范围1～100 μg·L-1(r=0.999 6),回收率在82.63%～92.41%,日内、日间RSD＜10%,最低定量浓度为1μg·L-1.结论:该法简便、快速、准确,适用于氯雷他定药动学和生物等效性研究.     

用固相萃取-高效液相色谱法测定氟康唑在健康人体的血药浓度

目的 建立氟康唑在健康人体血药浓度测定方法。方法 20名健康男性志愿者随机分成2组,交叉单剂量口服氟康唑150 mg后,采集血样,用高效液相色谱/紫外法检测氟康唑血药浓度。结果 氟康唑浓度在0.1～9.6 mg.mL-1线性关系良好(γ=0.9999),最低可定量浓度为0.1mg.mL-1,相对回收率大于95%,日内和日间RSD小于7%。结论 用固相萃取高效液相/紫外检测方法能快速可靠地测定氟康唑血药浓度,适于氟康唑的血药浓度监测和人体药代动力学研究。     

HPLC法测定人血浆中奥沙普秦浓度

目的:建立固相萃取高效液相色法测定人血浆中奥沙普秦浓度的方法,并应用于人体血浆药物浓度测定。方法:固相萃取净化和富集血浆样品。色谱柱为Kromasil C18柱,流动相为0.02 mol/L磷酸二氢钾缓冲液(pH 5.0)-甲醇(85∶15),流速为1.0 ml/min,紫外检测波长285 nm。血浆中内源性物质对样品测定无干扰。结果:本方法奥沙普秦线性范围为0.1～100μg/ml(r=0.999 2),最低定量浓度为0.1μg/ml,回收率为99.39%,日内、日间RSD均小于2%。结论:本法简便、准确,适用于奥沙普秦临床药物浓度测定。     

固相萃取—高效液相色谱法测定氯雷他定的血药浓度(英文)

目的建立固相萃取-高效液相色谱法测定氯雷他定血药浓度的方法。方法采用ODS-C18小柱处理样品,Zorbax SB-C18硅烷键合硅胶柱(4.6mm×250mm,5um),流动相:50mmol.L-1磷酸二氢铵缓冲液(磷酸调PH4.0)-乙腈(62∶38),流速:1.2mL.m in-1,检测波长:275nm。结果线性范围1~100 ng.mL-1(r=0.999 6),回收率在82.63%~92.41%,日内、日间RSD<10%,最低定量浓度为1ng.mL-1。结论该法简便、快速、准确,适用于氯雷他定药代动力血和生物等效性研究。     

Determination of fexofenadine in human plasma using 96-well solid phase extraction and HPLC with tandem mass spectrometric detection

A fast and sensitive HPLC-MS/MS method, utilizing atmospheric pressure chemical ionization, for the determination of fexofenadine in human plasma is described. A deuterated analog, d6-fexofenadine is used as the internal standard (IS). Plasma samples are prepared using 96-well solid phase extraction with plates containing Waters Oasis HLB sorbent. The analytes are chromatographed on a Restek Ultra IBD column (3.2 mm x 50 mm, 3 microm) using a mobile phase consisting of a mixture of 90% acetonitrile and 10% 10 mM ammonium acetate buffer and 0.1% formic acid. Quantitation of the analyte is based on the response from the multiple reaction monitoring of the precursor to product ion pairs for fexofenadine (m/z 502 --> 466) and d6-fexofenadine (m/z 508 --> 472). The assay has been validated over the concentration range of 1-200 ng/ml based on the analysis of 0.5 ml aliquots of plasma. Within-day assay accuracy was between 97 and 102% of nominal, while within-day precision was better than 3.5% CV at all points on the standard curve. Analyte extraction recovery was better than 70% over the range of the standard curve. The method was found to be suitable for the analysis of human plasma samples obtained 24 h following the administration of a single 60 mg dose of fexofenadine.     

A new validated method for the simultaneous determination of benzocaine, propylparaben and benzyl alcohol in a bioadhesive gel by HPLC

A new HPLC-RP method has been developed and validated for the simultaneous determination of benzocaine, two preservatives (propylparaben (nipasol) and benzyl alcohol) and degradation products of benzocaine in a semisolid pharmaceutical dosage form (benzocaine gel). The method uses a Nucleosil 120 C18 column and gradient elution. The mobile phase consisted of a mixture of methanol and glacial acetic acid (10%, v/v) at different proportion according to a time-schedule programme, pumped at a flow rate of 2.0 ml min⁻¹. The DAD detector was set at 258 nm. The validation study was carried out fulfilling the ICH guidelines in order to prove that the new analytical method, meets the reliability characteristics, and these characteristics showed the capacity of analytical method to keep, throughout the time, the fundamental criteria for validation: selectivity, linearity, precision, accuracy and sensitivity. The method was applied during the quality control of benzocaine gel in order to quantify the drug (benzocaine), preservatives and degraded products and proved to be suitable for rapid and reliable quality control method.     

Development and validation of amisulpride in human plasma by HPLC coupled with tandem mass spectrometry and its application to a pharmacokinetic study

In this study, authors developed a simple, sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantification of Amisulpride in human plasma using Amisulpride-d(5) as an internal standard (IS). Chromatographic separation was performed on Zorbax Bonus-RP C18, 4.6 × 75 mm, 3.5 μm column with an isocratic mobile phase composed of 0.2% formic acid:methanol (35:65 v/v), at a flow-rate of 0.5 mL/min. Amisulpride, Amisulpride-d(5) was detected at m/z 370.1→242.1 and 375.1→242.1. The drug and the IS were extracted by a liquid-liquid extraction method. The method was validated over a linear concentration range of 2.0-2500.0 ng/mL for Amisulpride with a correlation coefficient of (r(2)) ≥ 0.9982. This method demonstrated intra- and inter-day precision within 0.9 to 1.7 and 1.5 to 2.8 % and intra- and inter-day accuracy within 98.3 to 101.5 and 96.0 to 101.0 % for Amisulpride. Amisulpride was found to be stable at 3 freeze-thaw cycles, bench top and auto sampler stability studies. The developed method was successfully applied to a pharmacokinetic study.     

Simultaneous determination of nine major active compounds in Dracocephalum rupestre by HPLC

A new method was developed for the simultaneous determination of nine major constituents in Dracocephalum rupestre, including 5,7-dihydroxychromone (1), eriodictyol-7-O-β-d-glucoside (2), luteolin-7-O-β-d-glucoside (3), naringenin-7-O-β-d-glucoside (4), apigenin-7-O-β-d-glucoside (5), eriodictyol (6), luteolin (7), naringenin (8) and apigenin (9). The quantitative determination was conducted by reversed phase high-performance liquid chromatography with photodiode array detector (LC–PDA). Separation was performed on an Agilent Eclipse XDB-C₁₈ column (150 mm × 4.6 mm i.d., 5 μm) with gradient elution of acetonitrile and 0.5% aqueous acetic acid. The components were identified by retention time, ultraviolet (UV) spectra and quantified by LC–PDA at 260 nm. All calibration curves showed good linearity (r² > 0.999) within test ranges. The reproducibility was evaluated by intra- and inter-day assays and R.S.D. values were less than 3.0%. The recoveries were between 95.15 and 104.45%. The limits of detection (LOD) ranged from 0.002 to 0.422 μg/ml and limits of quantification (LOQ) ranged from 0.005 to 1.208 μg/ml, respectively. The identity of the peaks was further confirmed by high-performance liquid chromatography with triple-quadrupole mass spectrometry system coupled with electrospray ionization (ESI) interface. The developed method was applied to the determination of nine constituents in 14 samples of D. rupestre collected at various harvesting times. Most compounds accumulated at much higher amounts in about June–July. The satisfactory results indicated that the developed method was readily utilized as a quality control method for D. rupestre.     

Identification and quantification of 32 bioactive compounds in Lonicera species by high performance liquid chromatography coupled with time-of-flight mass spectrometry

Flos Lonicerae, referred to the flower buds of several medicinal Lonicera species, is a commonly used traditional Chinese herbal medicine. A multi-component-assay quality control method, using high performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry (HPLC-ESI/TOF MS), has been developed for the simultaneous identification and quantification of 32 bioactive compounds in Flos Lonicerae. The limits of detection (LOD) and quantification (LOQ) were in the range of 0.002–0.089 and 0.006–0.355 μg/ml, respectively. All calibration curves showed good linear regression (r² ≥ 0.99) within the test ranges. The overall intra- and inter-day precisions of analytes were less than 3.47% for peak area and 0.38% for retention time. The recoveries were from 85.4% to 101.6%. The validated method was applied to assay of 32 compounds in 8 medicinal Lonicera species. Furthermore, six unknown chromatographic peaks were tentatively characterized. It was demonstrated that the HPLC-ESI/TOF MS method was suitable for quality control of Lonicera species, owing to the advantages of accurate mass analysis, resolving power, enhanced selectivity and high sensitivity.     

Determination of Ciprofloxacin in Pharmaceutical Formulations Using HPLC Method with UV Detection

A simple, specific, accurate and rapid reversed phase high performance liquid chromatographic method was validated for the determination of the content of ciprofloxacin in three pharmaceuticals forms: generic, similar and compounded. The results of the validation showed that the method was highly efficient for quantification of ciprofloxacin in the matrices evaluated. The recovery rates were between 97.4 to 104.3 %, and the relative standard deviations were lower than 5 % for repeatability, and lower than 5.15 % for intermediate precision. The limits of detection, quantification and practical, were 0.11, 0.35 and 1.56 μg/ml, respectively. All compounded samples were approved with in the quality control; however, one generic and one similar sample presented above allowed level.     

固相萃取-离子交换色谱法检测枸杞子中多菌灵残留量

目的:建立固相萃取-离子交换色谱法检测枸杞子中多菌灵残留量。方法:样品用0.1%稀盐酸和乙腈提取,经 C_(18)固相萃取柱(SPE)和二氯甲烷液-液分配萃取(LLE)净化,采用 LC—SCX 离子交换色谱柱(25 cm×4.6 mm,5μm)分离,以0.1mol·L~(-1)磷酸二氢钾溶液(pH 3.2)-乙腈(70:30)为流动相,流速为1.0 mL·min~(-1),检测波长282nm。结果:样品中多菌灵能得到良好的分离,浓度在0.02～5 mg·L~(-1)范围内,与峰面积呈良好的线性关系(r=0.9999),回收率及重复性良好。结论:本法可用于枸杞子中多菌灵残留的检测。     

固相萃取-高效液相色谱法测定人血浆中的替硝唑浓度

目的建立固相萃取结合高效液相色谱法测定人血浆中替硝唑浓度的方法。方法血浆样品经C18固相萃取小柱净化后进样。色谱柱:HyperS il C18柱(250 mm×4.6 mm,5μm),流动相:磷酸二氢钾(含0.1%三乙胺,磷酸调pH=3.2)-乙腈(89∶11),柱温:25℃,流速:1 m L/min,检测波长:236 nm,进样量:30μL。结果替硝唑血药浓度在0.5~50 mg/L之间呈良好线性关系(r=0.999 5),线形方程Y=1.012 C-0.053 1,相对标准偏差<5%,回收率>90%。结论该方法操作简便、准确可靠,灵敏度高,适用于替硝唑的血药浓度检测。     

Simultaneous determination of eight active components in Chinese medicine 'JiangYaBiFeng' tablet by HPLC coupled with diode array detection

An effective, accurate and reliable method was developed for the simultaneous separation and determination of eight active components (baicalin, baicalein, sophoricoside, rutin, quercetin, genistein, pargyline and hydrochlorothiazide) in Chinese medicine 'JiangYaBiFeng' tablet (JYBF tablet) by high-performance liquid chromatography (HPLC) coupled with diode array detection (DAD). Due to the different UV characteristic of these components, different wavelengths were selected for analysis of different analytes, such as 210nm for pargyline, 256nm for sophoricoside, rutin, quercetin and genistein, and 280nm for baicalin, baicalein and hydrochlorothiazide. Excellent linear behaviors over the investigated concentration ranges were observed with the values of R(2) higher than 0.9990 for all analytes. The recovery rates and relative standard deviation (RSD) for all analytes at three different concentrations were 94.9-104.7% and 1.23-3.00%, respectively. The validated method was successfully applied to the simultaneously determination of these active components in 'JiangYaBiFeng' tablet from different production batches, indicating that the proposed method in this paper was particularly suitable for the routine analysis of JYBF tablet and its quality control.