Esters of cephalosporins. Part II. Differences in the properties of various forms of the 1-acetoxyethyl ester of cefuroxime.

Physico-chemical and microbiological properties of three different forms (crystalline and two amorphous ones) of the 1-acetoxyethyl ester of cefuroxime and bioavailability after oral administration to rats have been investigated. Relation between physico-chemical properties of these forms and their bioavailability is observed. It is shown, that for oral administration the most appropriate is an amorphous form obtained by rapid evaporation of a solvent from solution of the ester.