邻苯二甲醛-β-巯基乙醇组合试剂可视化荧光检测多巴胺

Visual Detection of Dopamine with o-Phthaldialdehyde-β-Mercaptoethanol Fluorogenic Reagent

研究发现，在碱性条件下，邻苯二甲醛和β-巯基乙醇组合试剂可与多巴胺发生化学反应生成异吲哚类化合物。当用340nm光激发时产生462nm的荧光，且荧光强度与多巴胺含量呈良好的线性关系，从而建立了一种可视化荧光检测多巴胺的新方法。在pH9．8的H3BO3-NaOH缓冲条件下，检测的线性范围为5．2×10^-8～1．7×10^-5mol／L，相关系数为0．9993，检出限（3σ）为4．1×10～mol／L。对7．0×10^-6mol／L的多巴胺进行11次平行测定，其相对标准偏差为1．4％。方法用于盐酸多巴胺注射液含量的分析，平均加标回收率为97．7％。以波长为365nm紫外灯激发多巴胺样品，可实现多巴胺可视化半定量检测。

A visual method for the determination of dopamine is described based on the fluorescence emission of a new isoindole compound formed by the reaction between dopamine and o-phthaldialdehyde-β-mercaptoethanol fluorogenic reagent in alkaline medium. A linear relationship has been obtained between the fluorescence intensity at 462 nm when excited by 340 nm and dopamine concentration in the range of 5.2 × 10^-8 - 1.7 ×10^-5 mol/L with the correlation coefficient of 0.9993 in borate buffer solution （pH = 9.8 ）. The detection limit is 4.1 × 10^-8s moL/L （3σ）, and the relative standard deviation is 1.4% （ c =7.0 × 10^-6 mol/L, n = 11 ）. The recommended method has been used for analysis of the injection containing dopamine hydrochloride with the recovery of 97.7%. A visual semi-quantificational method of dopamine could be proposed under the excitation of an ultraviolet light source.