A new approach to quantitative determination of γ-glutamyl-valyl-glycine in various aquatic products

A new method for determining the content of γ-glutamyl-valyl-glycine (γ-Glu-Val-Gly, γ-EVG) using high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) with precolumn derivatization by 2,4-Dinitrochlorobenzene (CDNB) was developed. The method exhibited satisfactory linear relationship (R² = 0.9995) at concentrations ranging from 1.0 to 40.0 ng/mL. The limits of detection (LOD) and quantitation (LOQ) were 0.3 and 0.9 ng/mL, respectively. Recoveries of the target peptide in spiked samples were between 83.05% and 116.49%, showing the values of relative standard deviation (RSD) less than 10%. The intra-day and the inter-day precisions were calculated to be 7.13% and 8.54% (n = 6), respectively. The validated approach was effectively applied to quantify the γ-EVG levels (0.13–0.38 μg/g) in different aquatic products. In conclusions, a sensitive, low-cost, convenient and reliable approach was developed for the detection of γ-EVG, which can serve as a potential tool for evaluating flavor peptide quality of aquatic products.     

柱前衍生HPLC法测定五谷虫中脂肪酸含量

目的 建立HPLC法测定五谷虫中脂肪酸含量的方法.方法 采用2-溴代苯乙酮作为衍生化试剂,三乙醇胺作为催化剂对脂肪酸进行衍生化使其产生紫外吸收,利用HPLC法进行含量测定.色谱条件为Agilent-C18柱(250 mm×4.6 mm,5 μm);检测波长254 nm;流动相为水∶甲醇=10∶90;柱温为20 ℃;体积流量为1 mL/min,进样量为20 μL,内标为十七烷酸.结果 在上述色谱条件下,各脂肪酸衍生物均达到基线分离.亚油酸的含量为131.0 mg/L,软脂酸的含量为194.8 mg/L,油酸的含量为100.6 mg/L,硬脂酸含量为36.6 mg/L.结论 该方法稳定,重现性好,可用于五谷虫脂肪酸含量测定.     

HPLC柱前衍生法测定舒血宁注射液中四种氨酸的含量

[目的]建立舒血宁注射液中4种氨基酸(天门冬氨酸、苏氨酸、丙氨酸、甲硫氨酸)的高效液相色谱(HPLC)柱前衍生化法,为舒血宁注射液的质量控制提供方法。[方法]以异硫氰酸苯酯(PITC)为柱前衍生化试剂,采用C18色谱柱,乙腈-水(5∶1)-乙酸铵缓冲溶液(p H 6.5)为流动相,梯度洗脱,检测波长为254 nm,测定舒血宁注射液中天门冬氨酸、苏氨酸、丙氨酸、甲硫氨酸的含量。[结果]4种氨基酸的分离及线性关系良好,精密度,重复性,稳定性RSD均都小于5%,平均回收率在95.6%~98.9%之间且RSD小于5%。舒血宁注射液中4种氨基酸总含量为1 738.47μg/mL。其中甲硫氨酸含量最高,丙氨酸的含量最低。[结论]本方法简便、准确、可靠,适用于舒血宁注射液中氨基酸含量的测定。     

柱前衍生化HPLC法测定复方氨基酸注射液(20AA)中氨基酸含量

目的: 建立柱前衍生高效液相色谱法测定复方氨基酸注射液（20AA）中包括门冬酰胺和盐酸鸟氨酸在内的18种氨基酸含量的方法。方法: 以6-氨基喹啉-N-羟基琥珀酰亚胺基氨基甲酸酯（AQC）为衍生化试剂,以γ-氨基丁酸为内标,采用Kromasil C18(250 mm × 4.6 mm, 5?m)色谱柱,以140 mmol?L-1醋酸铵缓冲液(pH5.10)和乙腈-水(57∶43)溶液为流动相进行梯度洗脱,检测波长为248 nm,进样量5?L。结果: 18种氨基酸在1.2～108.8 ?g?mL-1范围内浓度与峰面积线性相关,相关系数为0.994 7～0.999 7;在标示浓度的80％、100％、120％三个浓度水平的平均回收率为97.4％～103.1％,RSD为1.3％～3.7％(n=9)。结论: 本法操作简便,结果准确,优于现行标准的方法。     

Fluorescence detection of biotin using post-column derivatization with OPA in high performance liquid chromatography

A sensitive and selective high-performance liquid chromatographic method with post-column derivatization, using o-phthalaldehyde (OPA) and 3-mercaptopropionic acid (3-MPA), is described for the determination of biotin in pharmaceutical preparations. The use of 3-MPA gives intense fluorescent derivative and improves the stability of biotin fluorophore towards oxidation to the picomole level. The fluorophore was detected at 453 nm (excitation at 342 nm). The calibration graph was linear for 20–200 ng per injection. The detection limit of biotin under these conditions was about 10 ng per injection. The RSDs were 1.9–3.4%. This method could be applied to pharmaceutical preparations without interference of other compounds.     

盐酸芬氟拉明对映体的柱前衍生物GC法分析

以ω－莰烷酰氯为衍生试剂,采用柱前衍生化ＧＣ法,成功地分析了盐酸芬氟拉明、金刚乙胺和盐酸氯胺酮。光谱分析确证了芬氟拉明酰胺衍生物的结构,优化了盐酸芬氟拉明酰胺衍生物的结构,优化了盐酸芬氟拉明衍生条件,建立了盐酸花氟拉明的内标法定量分析方法。     

用均匀设计法优化β—环糊精手性固定相的衍生化反应工？…

采用均匀设计法对衍生化β－环糊精（β－ＣＤ）键合固定相的合成条件进行优化,考察的主要因素包括衍生化试剂异氰酸苯酯的用量、反应时间及反应温度。衍生化后β－ＣＤ键合相的碳含量优化结果预测值和实测值分别为１７．９５％和１８．１０％。采用红外光谱、热重分析曲线对衍生化前后β－ＣＤ键合固定相进行表征,探讨了衍生化前后β－ＣＤ键合相的手性拆分能力。     

Determination of a Hair Dye Using Different Derivatization Agents and HPLC in Combination with UV,Electrochemical, and Fluorescence Detection

Comparative studies using UV, fluorescence, and electrochemical detection after HPLC separation were performed to determine the hair dye N,N-bis(hydroxyethyl)-p-phenylenediamine PPDA . For the analysis of this substance in the extraction fluid with regard to skin permeation, sensitivity and selectivity were the most important parameters. Reaction with 2-(4-isocyanatophenyl)-6-methylbenzothiazole MBP and subsequent coulometric detection in the oxidative mode proved to be superior to fluorescence and UV detection. As future hair dyes may also possess amino and/or hydroxyl groups the method developed may be transferable.     

土鳖虫超微粉体中游离氨基酸的测定及指纹图谱研究

目的 建立土鳖虫超微粉体的游离氨基酸的HPLC指纹图谱,考察其主要氨基酸的量.方法 采用异硫氰酸苯酯(PITC)柱前衍生,梯度洗脱进行色谱分离,固定相为依利特Hypersil BDS C18柱(4.6 mm× 250 mm,5μm),流动相A乙腈-水(4∶1),流动相B醋酸钠缓冲溶液(pH=6.5)-乙腈(97∶3),检测波长为254 nm,体积流量为1 mL/min,柱温为30℃.结果 初步建立了土鳖虫超微粉体中游离氨基酸的HPLC指纹图谱,标定了24个共有峰,同时定量分析了6种氨基酸成分.结论 建立的方法分离效果好,灵敏、准确、简单,可作为土鳖虫超微粉体质量评价的方法.     

柱前衍生化UPLC测定板蓝根颗粒中主要游离氨基酸的含量

目的:采用柱前衍生化法测定板蓝根颗粒中6种游离氨基酸的含量.方法:采用6-氨基喹啉基-N-羟基琥珀酰亚氨基甲酸酯(AQC)进行柱前衍生化,超高效液相色谱法测定板蓝根颗粒中精氨酸、脯氨酸、苏氨酸、丙氨酸、γ-氨基丁酸、缬氨酸的含量.Waters AccQ Tag TM Ultra C18色谱柱(2.1 mm×100 mm,5μm),流动相AccQ Tag Ultra Eluent A与AccQ Tag Ultra Eluent B进行梯度洗脱,流速0.7 mL·min-1,柱温55℃,检测波长260 nm.结果:精氨酸的线性范围为4.155 ～49.86 μg,r=0.999 9;苏氨酸的线性范围为0.595 ～5.95 μg,r =0.999 8;丙氨酸的线性范围为0.445 ～4.45 μg,r =0.999 9;γ-氨基丁酸的线性范围为0.515 ～5.15μg,r=0.999 9;脯氨酸的线性范围为8.858 ～ 106.3 μg,r=O.999 9;缬氨酸的线性范围为0.585～5.85μg,r=0.999 8.平均回收率分别为100.6％,98.34％,98.35％,100.2％,98.44％,98.18％;平均RSD分别为1.8％,1.5％,1.9％,2.0％,2.4％,2.0％(n=6).5家企业的的板蓝根颗粒中氨基酸类成分的含量存在差异.结论:该方法操作简单,重复性好,灵敏度高,结果准确可靠.