High-performance liquid chromatography of preparations of ribonucleic acid inactivator(s) from cupric ion and hydroquinone before and after treatment with histidine.

Preparations of viral RNA inactivator(s) produced during the cupric ion-catalyzed oxidation of hydroquinone were analyzed by high-performance liquid chromatography (HPLC) using UV and electrochemical (EC) detectors. In addition to hydroquinone and the main oxidation product (p-benzoquinone), which is known not to be the inactivator(s), the analysis showed three unidentified components (I-III). Partial UV absorption spectra of I-III were determined by HPLC with the UV detector set at various wavelengths. Components II and III, but not I, were highly unstable in the presence of L-histidine, which is an excellent chelator of cupric ion and can promptly stop ongoing viral RNA inactivation by the inactivator(s). The product p-benzoquinone was also highly unstable in the presence of L-histidine; the reaction between these two compounds (with or without copper) resulted in a cascade of products. The possibility that the inactivator(s) is II or III, or both, is discussed.