药物中半胱氨酸的流动注射荧光测定方法研究

 在近中性介质及聚乙烯醇(PVA)存在下,半胱氨酸能熄灭一个新的荧光试剂5-(4-氯苯基)-8-苯磺酰氨基喹啉(CPBSQ)与Cu(Ⅱ)络合体系的荧光的反应.基于此现象,本文建立了一个测定半胱氨酸的流动注射荧光熄灭方法.结果表明,在λ_ex/λ_em=327/368nm处测定,方法的进样频率为64h-1,检测范围为0.05～5.5μg·mL^-1,检出下限为0.01μg·mL^-1,对4.0μg·mL^-1半胱氨酸平行测定11次的相对标准偏差为1.52%.大量存在的常见金属离子、蛋白质及很多不带巯基的氨基酸不干扰测定.应用此方法测定了某些注射液针剂中半胱氨酸的含量,结果满意.

Study on the flow injection method for the fluorescence determination of L-cysteine in the medicine injection

A flow injection method for the fluorescence determination of L cysteine in the medicine injection has been developed based on the fluorescence quenches of the complex system between a new fluorescence reagent:5-(4-chlorophenylazo)-8-benzenesulfonamidoquinoline (CPBSQ) and Cu(II) cysteine.The determination is carried out at λ_ex/λ_em=327/368nm.The sample frequency of the method is 64h^-1 with a linear range of 0.05-5.5μg·mL^-1 and a detection limit of 0.01μg·mL^-1.The relative standard deviation (RSD) for the determination of 11 samples of 4.0 mg·L^-1 cysteine is 1.52%.A lot of metal ions,protein and amino acid without-SH group do not interfere the determination.The proposed method has been applied to the determination of cysteine in the medicine injetion with satisfactory results.