A silica gel-bound molecularly imprinted polymer to oxazolone(s) exclusively derived from certain cephalosporins (cefaclor) and penicillins (amoxycillins and ampicillins) was prepared using ethylacetate as a porogen. This was used as a packing material for solid phase extraction in column chromatography. The high selectivity and the quantitative sorption of oxazolone at pH 7.5 and a flow rate of 5.0 ml min(-1) in a long (13.0 cm) and wide bore ( 1.4 cm internal diameter) column have led to efficient clean-up, selective enrichment, and indirect differential pulse adsorptive stripping voltammetric measurement of the beta-lactams in the form of corresponding oxazolones either in a larger volume of dilute aqueous systems or in the pharmaceutical formulations, without complications of complex matrices, excipients or column deterioration. (C) 2003 Elsevier Science B.V. All rights reserved.