一种快速测定蒽醌含量的可见光谱方法

Rapid Determination of Anthraquinone by Visible Spectroscopy

关键词:  可见光谱法  蒽醌  蒽氢醌  连二亚硫酸钠

Key Words:visible spectroscopy  anthraquinone  anthrahydroquinone  sodium dithionite

摘要:介绍了一种快速测定蒽醌含量的可见光谱方法。本方法是基于用连二亚硫酸钠（Na₂S₂O₄）在碱性条件下将蒽醌（AQ）还原成蒽氢醌（AHQ），然后在505 nm处检测AHQ的吸光度而建立的。结果表明，将AQ转化成AHQ的最佳还原条件为：温度80℃，时间10 min，AQ、Na₂S₂O₄和NaOH的摩尔比为1∶3∶50。本方法的相对标准偏差为2.01%；定量检测极限为2.26 mg/L；回收率在95.5%～100%。本方法完全满足商品蒸煮助剂中AQ含量检测的要求。

Abstract:A spectroscopic method for determination of dispersible anthraquinone (AQ) in aqueous solution was reported in this study. The method is based on the reaction between AQ and sodium dithionite in an alkaline medium, and AQ is converted to anthrahydroquinone (AHQ) that is measured with spectrophotometer at a wavelength of 505 nm. Results showed that a complete conversion of AQ to AHQ could be achieved within 10 min at a temperature of 80℃, in which the molar ratio of sodium hydroxide: sodium dithionite: AQ was 50∶3∶1. The results showed that the present method had a good repeatability (RSD<2.01%); the limit of quantification (LOQ) was 2.26 mg/L and the recovery ranged from 95.5%~100%. The present method is simple, rapid, and accurate.