Electronic Spectra of N-Methyl 8-Hydroxy Quinoline Methyl Sulphate Adsorbed on Sepiolite

Abstract

Adsorption of the drug N-methyl 8-hydroxy quinoline methyl sulphate, used to prevent sunburning and to avoid the dangerous effect of erythematogenic radiations, on untreated and HCl-treated sepiolite has been studied. The adsorption complex formed extends the absorption properties of the drug in the visible and ultraviolet range. The behaviour shown by these samples is fairly similar in all cases with respect to light absorption. However, adsorption complexes prepared via a dry method, by mechanically mixing the drug and sepiolite, lead to samples with different light absorbent properties, due to the modification of the surface acid/base properties of the sepiolite and hence of the way the drug is adsorbed.

Key Words:

• electronic spectra
• sepiolite
• drug-clays interaction