胶束增敏同步荧光-双波长法同时测定血浆中儿茶酚胺类神经递质

采用胶束增敏结合同步荧光-双波长法,建立一种同时测定肾上腺素(E)、去甲肾上腺素(NE)和多巴胺(DA)3种儿茶酚胺类神经递质的方法.实验体系添加增敏性剂,对E,NE和DA 3种神经递质的衍生物分别进行同步扫描,考察胶束增敏效果以及影响荧光强度的pH值、有序介质(表面活性剂和环糊精)的种类和用量、反应时间、产物稳定性等因素.最佳实验条件为:0.3 mol/L乙酸-乙酸钠缓冲液(pH=4.6),E,NE和DA的加热时间分别为1,2和40 min,eλx=300.0 nm,Δλ=70.0 nm.结果表明:上述条件获得的同步荧光光谱图中,DA在385.0 nm处的荧光信号不受干扰,而且E和NE的相互干扰可通过双波长法消除.E,NE和DA线性范围分别为0.40~32.00μg/L,2.45~54.00μg/L和0.40~45.00μg/L,相关系数分别为0.999 4,0.999 5和0.999 4;检测限分别为0.09,0.27和0.08μg/L.该法可以用于血浆中儿茶酚胺类神经递质的同时测定,使检测限降低.

Simultaneous Determination of Catecholamines Neurotransmitters in Blood Plasma by Micellar Enhanced Synchronous Scanning-dual Wavelength Fluorimetry

A micellar enhanced synchronous scanning-dual wavelength fluorimetric method for simultaneous determination of epinephrine,norepinephrine and dopamine has been described.After adding the sensitizing reagent,the ramifications of E,NE and DA have been respectively scanned simultaneously to examine the effect of the micellar enhanced and the factors as pH,the type and dosage of ordered medium(surfactants and cyclodextrin),reaction time,product stability,and so on which affect the intensity of systematic fluorescence.The results showed that when λ_ex was 300.0 nm,Δλ was 70.0 nm,the largest fluorescence signal of DA,which was 385.0 nm,was not disturbed in the simultaneous fluorescence spectrum gained and the mutual interference of E and NE could be eliminated by the dual-wavelength method.The largest fluorescence intensity could be got in 0.3 mol/L acetic acid-sodium acetate buffer at pH 4.6 and the heating time of E,NE and DA were 1 min,2 min and 40 min respectively.The linear ranges were 0.40～32.00 μg/L(r = 0.999 4) for epinephrine,2.45～54.00 μg/L(r = 0.999 5) for norepinephrine and 0.40～45.00 μg/L(r = 0.999 4) for dopamine.The detection limits of E,NE and DA were 0.09,0.27 and 0.08 μg/L respectively.Satisfactory results were obtained by the proposed method for determination of trace amounts of neurotransmitters in several synthetic samples.