Photodegradation of drug substances can produce both known and unknown products that interfere with analytical results due to absorption at certain wavelengths.
The study focuses on improving the accuracy of measurements for methylcobalamin (MC) and hydroxocobalamin by applying linear and non-linear methods to correct for irrelevant absorbances during photolytic degradation involving ascorbic acid (AH).
Methylcobalamin shows first-order degradation kinetics, with the degradation rate being pH-dependent; it peaks at pH 5.0 when in the presence of ascorbic acid, whereas degradation slows down in more alkaline conditions.