On the thermal and chemical stability of molecularly imprinted polymers

The thermal and chemical stability of a theophylline imprinted methacrylic acid-ethylene glycol dimethacrylate co-polymer has been investigated. Radio ligand binding studies have been used to study the changes in theophylline recognition characteristics of this and a non-imprinted, reference polymer arising from exposure to elevated temperatures and a range of chemical envi ronments. Polymers were shown to withstand exposure to temperatures of up t o 150 degreesC (for 24 h) without loss of affinity for the template. Temper atures above this point induced a rapid loss in binding capacity and a conc omitant mass loss. FT-IR indicated that this arises from decarboxylation of the polymer. The polymers exhibited remarkable resistance to extremes of p H, organic base and to autoclave treatment. This study provides an indicati on as to the limits of polymer stability, which is of significance for the practical use of this type of polymer, e.g. in sensor-based applications. ( C) 2001 Elsevier Science B.V. All rights reserved.