'Bite-and-Switch' approach using computationally designed molecularly imprinted polymers for sensing of creatinine

A method for the selective detection of creatinine is reported, which is ba sed on the reaction between polymerised hemithioacetal formed by allyl merc aptan, o-phthalic aldehyde, and primary amine leading to the formation Of f luorescent isoindole complex. This method has been demonstrated previously for the detection of creatine using creatine-imprinted molecularly imprinte d polymers (MlPs) Since MlPs created using traditional methods were unable to differentiate between creatine and creatinine, a new approach to the rat ional design of a molecularly imprinted polymer (MIP) selective for creatin ine was developed using computer simulation. A virtual library of functiona l monomers was assigned and screened against the target molecule, creatinin e, using molecular modelling software. The monomers giving the highest bind ing score were further tested using simulated annealing in order to mimic t he complexation of the functional monomers with template in the monomer mix ture. The result of this simulation gave an optimised MIP composition. The computationally designed polymer demonstrated superior selectivity in compa rison to the polymer prepared using traditional approach, a detection limit of 25 muM and good stability. The 'Bite-and-Switch' approach combined with molecular imprinting can be used for the design of assays and sensors, sel ective for amino containing substances. (C) 2001 Elsevier Science B.V. All rights reserved.