Development of Molecularly Imprinted Polymers for Drug Delivery Applications Using Supercritical Fluid Technology

Molecular imprinting is an emerging field that produces precise chemical and physical architectures that can bind analytes. The technique uses the functionality of the target molecule (template) to assemble a molecular recognition site by forming specific interactions with the matrix. We have recently proposed supercritical fluid technology to replace hazardous organic solvents in the synthesis of these high affinity materials, also improving a lot the final product in terms of morphology avoiding multiple drying and sieving steps. In this work weakly cross-linked imprinted polymers with molecular affinity to ibuprofen were synthesized in scCO2 at 65 oC and 21 MPa, using DMAEMA as functional monomer and EGDMA as cross-linker agent. After impregnation at 40 oC and 20 MPa, the polymers were tested as controlled drug release devices in PBS pH 7.4 at 37 oC. Our results show that even with a flexible, less cross-linked structure, macromolecular memory is achieved and significant different performences in drug delivery are obtained between imprinted and nonimprinted polymers.