毛细管电泳-激光诱导荧光法分离四种神经递质类氨基酸的条件优化

目的探讨毛细管电泳分离神经递质类氨基酸的影响因素。方法采用毛细管电泳法分离4种神经递质类氨基酸的荧光素异硫氰酸酯(FITC-AAs)衍生物,分析电泳缓冲液、表面活性剂以及衍生条件对分离的影响。结果电泳缓冲液的组成、浓度、pH值、表面活性剂以及衍生条件对4种FITC-AA衍生物分离有很大影响,在以75 mm ol/L,pH 9.42硼酸盐含100 mm ol/LSDS为电泳缓冲液,50 mmol/LpH 9.8硼酸盐为衍生缓冲液,4种FITC-AA衍生物20 min内得到很好分离。结论通过条件优化,毛细管电泳-激光诱导荧光技术分离神经递质类氨基酸的分离效果能得到很大提高。     

Bioadhesive vaginal drug delivery of nystatin using a derivatized polymer: Development and characterization

Increasing incidence of resistance to azole antifungals has highlighted the importance of the use of alternative therapeutic agents such as nystatin for the treatment of vulvovaginal candidiasis. The aim of the present study was to develop and characterize locally acting, film formulation for the treatment of candidiasis using a derivatized natural polymer. Derivatization of natural polymer was carried out in order to introduce anionic character to an otherwise neutral polymer, so as to enhance its interaction with vaginal mucous membrane along with inheriting the biocompatibility and nonirritant characteristics of its parent polymer. A carboxymethyl derivative of fenugreek gum (CMFG) was prepared, and characterized by DSC, FTIR and X-ray diffraction studies. The derivatized gum was found to possess bioadhesive and film forming properties. A 3² factorial design was employed to formulate vaginal films and a response surface methodological approach was used to study the effect of formulation variables on film properties. Films containing 5% w/v polymer and 2% v/v glycerol exhibited optimum properties in vitro. The optimized drug loaded formulation was able to release 100% drug over a period of 5 h and followed Korsmeyer–Peppas kinetics. It was found to be non-irritant and nontoxic to vaginal mucosa and showed appropriate antifungal properties in vivo.     

高效液相色谱法测定金糖宁胶囊中1-脱氧野尻霉素的含量

目的:建立反相高效液相色谱-柱前衍生化法测定金糖宁胶囊中1-脱氧野尻霉素(1-DNJ)的含量。方法:样品经处理过的D001-CC型阳离子交换树脂上用氨水洗脱收集后,用2 g·L-1的芴甲氧羰酰氯(FMOC-C1)柱前衍生化,再采用高效液相色谱-二极管阵列检测器测定。ODS-C18色谱柱(4.0 mm×250 mm,5μm),流动相乙睛-0.2%磷酸溶液梯度洗脱,流速1.0 m L·min-1,检测波长263 nm,柱温25℃。结果:1-脱氧野尻霉素在0.84~8.4μg线性关系良好(r=1.000 0),精密度RSD0.3%,重复性RSD 0.6%,衍生化后的样品溶液在24 h内稳定,平均回收率109.6%,RSD 0.4%。结论:该方法稳定可靠,重复性好,精密度高,可用于金糖宁胶囊中1-脱氧野尻霉素的含量测定。     

柱前衍生化HPLC测定石榴籽油中石榴酸的含量

目的:石榴酸(C18∶3)在结构上为顺9,反11,顺13-十八碳三烯酸,为长链烃类,在200~400 nm没有吸收,无法直接用紫外检测器进行检测,本实验采用柱前衍生化方法,使石榴酸带上一个强发色团,使其在200~400 nm有最大吸收,建立石榴籽油中指标性成分石榴酸的柱前衍生化HPLC分析方法。方法:以ω-溴代苯乙酮作为衍生化试剂,以三乙醇胺为相转移催化剂,对石榴籽油进行柱前衍生化,色谱条件采用Diamonsi C18色谱柱(4.6 mm×250 mm,5μm),检测波长272 nm,以甲醇-乙腈-水(68.5∶20∶11.5)为流动相,柱温30℃,流速1.0 m L·min-1。结果:石榴酸在0.026 6~0.133 0 g·L-1(r=0.999)线性关系良好,平均加样回收率为98.7%,RSD 1.8%。结论:该法稳定性、重复性好,定量准确,可作为石榴籽油中石榴酸的定量方法,用于评价和控制石榴籽油的质量。     

庆大霉素C组分和有关物质测定的HPLC-柱后衍生化法与脉冲安培电化学法的比较研究

摘 要 目的： 参考《欧洲药典》的HPLC 脉冲安培电化学法建立高效液相色谱 柱后衍生化法测定庆大霉素C组分含量及其有关物质, 同时与电化学法进行比较研究。方法: 采用亲水性HydrosphereC₁₈（250 mm×4.6 mm,5 μm）色谱柱,以含0.7%三氟乙酸及0.025%五氟丙酸的50 mmol·L^-1氢氧化钠溶液（pH2.6）-乙腈（98.5∶1.5）为流动相。衍生化法反应温度30℃,荧光激发波长340 nm,发射波长430 nm。电化学法采用脉冲安培检测器,金电极为工作电极,四电位波形工作模式。结果:两种方法测定的庆大霉素C组分（C_1a, C₂, C_2a和C₁）分别在5.82～233.00,6.92～277.00,4.00～160.00和6.23～249.00 μg·mL^-1的浓度范围内线性关系良好（r均≥0.999 3）,检测限和定量限范围分别为0.92～3.28 ng和1.37～5.19 ng。结论: 两种方法的检测结果无明显差异。     

Investigation of amino acids in wolfberry fruit (Lycium barbarum) by solid-phase extraction and liquid chromatography with precolumn derivatization

The aim of this work is to present a simple and sensitive reverse-phase liquid chromatography method for the determination and investigation of amino acids in wolfberry fruit (Lycium barbarum) after solid-phase extraction-derivatization. The method linearity, calculated for each amino acid, had a correlation coefficient higher than 0.9950, in concentrations ranged from 9.60 to 3.33 × 10³ μmol L⁻¹. The detection limits of amino acids were between 2.42 and 6.51 μmol L⁻¹. The calculated recoveries for amino acids in wolfberry fruit were from 87.3% to 97.1% and relative standard deviations were from 2.62% to 5.22%. The investigation illustrated that each tested wolfberry fruit contained at least 16 amino acids and the main amino acids were glutamic acid, aspartic acid, proline, alanine, serine, glycine, lysine, and tyrosine. The levels of amino acid in wolfberry fruit were varying from different areas.     

Quantification and validation of nine nonsteroidal anti‐inflammatory drugs in equine urine using gas chromatography–mass spectrometry for doping control

Nonsteroidal anti‐inflammatory drugs (NSAIDs) are commonly used in therapeutic doses in human and veterinary medicine for the treatment of inflammation, pain, and fever. A method for the simultaneous determination of nine NSAIDs, known as therapeutic prohibited substances, in equine urine was developed and fully validated according to the European Commission Decision 2002/657/EC and Association of Official Racing Chemists criteria. The validation was performed for naproxen, flunixin, ketoprofen, diclofenac, eltenac, meclofenamic acid, phenylbutazone, vedaprofen, and carprofen in equine urine in accordance with the International Screening Limits (ISL) regulated by International Federation of Horseracing Authorities. After basic hydrolysis, samples were extracted with a C18 cartridge using automated solid‐phase extraction. Several derivatization reagents were investigated, and trimethylphenylammonium hydroxide/methanol (20/80, v/v) was selected. Analyses were carried out using gas chromatography–mass spectrometry with selected ion monitoring mode, but the method can be applied to a large number of analytes. The within‐laboratory reproducibility was not more than 12.8% (≤15%), and mean relative recoveries ranged from 91.1% to 104.1% for inter‐day and intra‐day precision. The decision limits (CCα) and detection capabilities (CCβ) were evaluated at concentrations near the ISL for each therapeutic substance. The validation results demonstrated that the method is highly reproducible, easily applicable, and suitable for the analysis of some NSAIDs in equine urine that have not been previously published. Finally, the method was also applied to known positive samples.     

柱后衍生化 -HPLC 法测定硫酸卡那霉素注射液 及滴眼液的含量

目的 新建硫酸卡那霉素注射液及滴眼液含量的高效液相色谱 - 柱后衍生化 - 荧光检测方法。方法 色谱柱为 Zorbax Eclipse Plus C18 (4.6mm×100mm, 3.5μm);流动相为 pH3.4 的缓冲液 ( 取庚烷磺酸钠一水合物 4.35g 和无水硫酸钠 16g,加水 溶解并稀释至成 1000mL,用冰醋酸调节 pH 值至 3.4±0.1)- 甲醇 (74:26);柱温为 35℃;流速为 1mL/min。柱后衍生化试液为邻苯 二甲醛溶液;流速为 0.3mL/min;衍生化反应温度为 45℃;荧光激发波长为 340nm,发射波长为 455nm。结果 卡那霉素 A 在 0.0973~583.8μg/mL 浓度范围内线性关系良好 (r=0.9999),硫酸卡那霉素注射液和滴眼液的平均回收率分别为 99.6% 和 99.3%, RSD 为 0.63% 和 0.66%(n=9)。结论 本方法检测灵敏度高,重复性好,简便快速,结果准确可靠,可作为硫酸卡那霉素注射液 及滴眼液的含量测定方法。     

柱前衍生HPLC法测定干髓糊剂中多聚甲醛的含量

目的:建立测定干髓糊剂中多聚甲醛含量的方法。方法:采用2,4-二硝基苯肼柱前衍生高效液相色谱法。色谱柱为Diamonsil C18(2),流动相为甲醇-水(60∶40,V/V),流速为1.0 ml/min,检测波长为355 nm,柱温为25℃。结果:多聚甲醛(以甲醛计)检测质量浓度线性范围为5.05²52.50μg/ml(r=0.999 7);精密度、重复性、稳定性试验的RSD均小于2%;平均加样回收率为99.12%,RSD=1.86%(n=9)。结论:建立的方法专属性强,结果准确可靠,可用于干髓糊剂中多聚甲醛的含量测定。     

A high‐throughput LC‐MS/MS screen for GHRP in equine and human urine,featuring peptide derivatization for improved chromatography

The growth hormone releasing peptides (GHRPs) hexarelin, ipamorelin, alexamorelin, GHRP‐1, GHRP‐2, GHRP‐4, GHRP‐5, and GHRP‐6 are all synthetic met‐enkephalin analogues that include unnatural D‐amino acids. They were designed specifically for their ability to stimulate growth hormone release and may serve as performance enhancing drugs. To regulate the use of these peptides within the horse racing industry and by human athletes, a method is presented for the extraction, derivatization, and detection of GHRPs from equine and human urine. This method takes advantage of a highly specific solid‐phase extraction combined with a novel derivatization method to improve the chromatography of basic peptides. The method was validated with respect to linearity, repeatability, intermediate precision, specificity, limits of detection, limits of confirmation, ion suppression, and stability. As proof of principle, all eight GHRPs or their metabolites could be detected in urine collected from rats after intravenous administration. Copyright © 2014 John Wiley & Sons, Ltd.