Photodestruction of active pharmaceutical substances in the presence of hydrogen peroxide and peroxydisulfate

Abstract

Studies into photochemical oxidation can enhance the current understanding of degradation processes within aqueous solutions of active pharmaceutical ingredients (APIs). APIs are complex decomposable compounds that, once in reservoirs, cause irreversible consequences in living organisms. The results obtained on the photodestruction of various drugs in water in the presence of hydrogen peroxide and peroxydisulfate contribute to gaining new practical and theoretical knowledge in the field of water treatment, post-treatment, and purification. The paper presents laboratory results on the oxidation of model aqueous solutions of nitrofural, tetracycline, and paracetamol under the combined effect of UV radiation with micro-additives of oxidants (hydrogen peroxide and peroxydisulfate). The reaction order of APIs destruction is determined by the least square method. The results show that the combined effect of UV radiation and microadditives of hydrogen peroxide and peroxydisulfate contributes to both a high degree of purification (up to 98%) and a high rate of oxidative degradation of APIs (nitrofural, tetracycline, and paracetamol) compared to the use of UV radiation separately. The studied drugs can be arranged in the following order in terms of their oxidative degradation transformation ability: nitrofural>tetracycline>paraceta mol. The paper theoretically proves that photochemical destruction in the presence of peroxydisulfate leads to the formation of more highly reactive oxygen-containing radicals, which are involved in the decomposition of nitrofural, tetracycline, and paracetamol.