P.3.035 Generalized anxiety and major depression in a Belgian primary care setting, influence by socio-economic factors. The GADIS II study

Abstract

The effect of ultraviolet radiation on the photolability of nitrofurazone in aqueous solutions was followed by a stability-indicating paper chromatographic method. Various factors including the pH of the medium, the presence of surfactants, polyethylene glycols, metal ions or ultraviolet light absorbers influenced the rate of photodecomposition of the drug. The photodecomposition of nitrofurazone in aqueous solution followed apparent zero-order kinetics. In the polyethylene glycol or aqueous solution the rate was much lower than that in the surfactants. The process of photodecomposition was accelerated by ferric ions while slightly inhibited by cupric ions. It was found that the rate constant increased initially with the incorporation of a small amount of the ultraviolet light absorbers. Subsequently, the rate constant decreased with increasing concentration of ultraviolet light absorber. Uvinul D-50 shows a higher stabilizing effect than Uvinul N-35. There was little thermal degradation of the drug in comparison to the decomposition by irradiation with ultraviolet light at the temperature of the study. Thermal degradation followed a first order rate process.