Photochemical Reaction of Nalidixic Acid in Methanol
The photochemical reactions of methanolic nalidixic acid (NAL) solution in the absence and in the presence of air have been investigated using 300 nm UV light. From the reactions, 1-ethyl-7-methyl-4-oxo-4-hydro-1,8naphthyridine (EMDN), formic acid, and formaldehyde are produced. In the presence of air, hydrogen peroxide is also detected along with the products listed above. The presence of oxygen during the irradiation of methanolic NAL solution effects on the product yield. The initial quantum yields of the products and of the NAL decomposition are determined. Possible reaction pathways for the photochemical reaction are suggested on the basis of the products analysis.
Colorimetric determination of iron in vitamin supplement tablets. A general chemistry experiment.
The basic concepts of instrumental analysis are introduced through modification of a standard procedure for the colorimetric determination of iron.
Bullous photoreaction to nalidixic acid.
Curtaneous blisters developed after exposure to the sun in two women who were taking nalidixic acid. Blisters continued to appear even after therapy was discontinued and there was no further exposure to the sun. Phototesting showed abnormal sensitivity to both short and long wavelength ultraviolet spectra in one patient. The low incidence of this phenomenon suggests a photoallergic mechanism, but features of both photoallergy and phototoxicity are present.