间氯偶氮安替比林双波长分光光度法同时测定钙和镁的研究

Study on the Dual-wavelength Spectrophotometric Determination of Calcium and Magnesium with m-chloroantipyrlazo

本文着重研究了用间氯偶氧安替比林作为显色剂,在 pH=10的硼砂缓冲溶液中,以三乙醇胺作为掩蔽剂,用双波长分光光度法同时测定钙和镁的新方法。测定钙选用655nm—587nm 作为波长对,测定镁选用600nm—674nm 作为波长对,有效地消除了钙镁之间的相互干扰。钙和镁的量均在5—30μg/25cm^3范围内符合比耳定律。提出的方法具有简便快速的特点,用于水样中钙和镁的同时测定,结果与原子吸收法测定值基本一致,回收率也令人满意。

In this paper,the method of dual-wavelength spectrophotometric determination of Ca andMg in water with the chromogenic reagent m-chloroantipyrlazo is described.In 2% borax buffersolution(pH=10),Ca and Mg can form stable complex with the reagent,the maxium absorption is 631nm and 615 nm respectively.The measuring wavelength and referential wavelength are 655 nm and587 nm for Ca,600 nm and 674 nm for Mg.The calibration curves for Ca and Mg are linear in therange of 5 to 30 μg/25cm^3.Most of the foreign ions do not interfere with the determination.Thepresent method is sample and rapid.The results obtained agree well with those by atomic abstorption spectrometry.