Spectrophotometric determination of p-quinones with N,N-diethy-1,4-phenylenediamine

Abstract

A spectrophotometric method for the determination of p-quinones was established with N,N-diethy-1,4-phenylenediamine. In the determination of 2,3-dimethoxy-5-methyl-1,4-benzoquinone (DMBQ), Beer’s law was obeyed in a concentration range of 0.1∼1.5 μg/ml of DMBQ. The apparent molar absorptivity was 1.1 × 10⁵ l mol^{− 1} cm^{− 1} at 552 nm. The relative standard deviation for six replicate determinations for 0.18 μg/ml was 0.48%.