Cyclodextrin-accelerated degradation of β-lactam antibiotics in aqueous solutions

Abstract

The catalytic effect of heptakis(2,6-di- O-methyl)- β-cyclodextrin, 2-hydroxypyl-β-cyclodextrin, 2-hydroxypropyl-γ-cyclodextrin and glucose on the degradation of aztreonam and phenoxymethylpenicillin in aqueous buffer solutions has been studied. All three cyclodextrin derivatives and glucose increased the rate of degradation of aztreonam. The two hydroxyprophyl cyclodextrin derivatives also accelerated the degradation of phenoxymethylpenicillin. This effect of cyclodextrins on β-lactam antibiotics will limit their usage in pharmaceutical preparations containing these drugs.