Direct Extraction of Penicillin G and Derivatives from Aqueous Samples Using a Stoichiometrically Imprinted Polymer

Abstract

A molecularly imprinted polymer (MIP) prepared using penicillin G procaine salt as the template (PENGp) and a stoichiometric quantity of urea-based functional monomer to target the single oxyanionic species in the template molecule has been applied to the development of a molecularly imprinted solid-phase extraction (MISPE) procedure for the selective preconcentration of beta-lactam antibiotics (BLAs) from environmental water samples. Various parameters affecting the extraction efficiency of the polymer have been evaluated to achieve the selective preconcentration of the antibiotics from aqueous samples and to reduce nonspecific interactions. This resulted in an MISPE-HPLC method allowing the direct extraction of the analytes from the sample matrix with a selective wash using just 10% (v/v) organic solvent. On the basis of UV detection only, the method showed good recoveries and precision, ranging between 93% and 100% (RSD 3.8-8.9%, n = 3) for tap water and between 90% and 100% (RSD 4.2-9.1%, n = 3) for river water fortified with 30 or 60 microg L-1 (50 mL samples) penicillin G, penicillin V, nafcillin, oxacillin, cloxacillin, and dicloxacillin, suggesting that this MIP can be successfully applied to the direct preconcentration of BLAs in environmental water samples.

Protein-selective adsorbers by molecular imprinting via a novel two-step surface grafting method

“…For the conventional small molecular imprinting, scaffold monomers with multi scaffold elements were used to improved the imprinting property such as urea, [37] ethylenediaminetetraacetic acid (EDTA) / diethylenetriamine pentaacetic (DTPA), [38] and cyclodextrin.…”

Influence of salt ions on binding to molecularly imprinted polymers

“…Water may interfere with hydrogen bonds involved in the recognition and MIPs relying on non-covalent interactions to the template are therefore often prepared in aprotic organic media. Optimal rebinding is usually observed in similar aprotic organic solvents as the ones used during the imprinting, although several cases of successful rebinding in aqueous media have been reported [8,[16][17][18][19][20][21][22][23][24][25]. The pH and the ionic strength of the rebinding solvent mixture have been recognized as parameters affecting the binding capacity [16,19,26].…”

Current status and challenges of ion imprinting

“…266 Penicillin G, a kind of b-lactam antibiotic, was developed as an imprinted polymeric receptor, which was applied to a SPE procedure for the selective pre-concentration of BLAs from environmental samples. 267,268 Schmitzer and coworkers 269 used a self-synthetic monomer di(ureidoethylenemethacrylate)azobenzene and methotrexate analogue (bis(TBA)-N-Z-L-glutamate) as a template to obtain good selective photoresponsive polymers. Photoinduced cis / trans isomerization of theazobenzene-containing polymer backbone is able to regulate the receptor sites' geometry and can regulate the release and uptake of a substrate, as shown in Fig.…”