Biomimetic Polymers in Drug Delivery and Sensing Applications: Effect of Network Molecular Structure on Recognition Properties

Biomimetic polymer networks have been developed with tailored affinities and transport properties for a given target molecule, and these networks promise to significantly impact a wide variety of biomedical fields, including controlled drug delivery and biosensing. Biosensors typically employ biological compounds as recognition elements, and biomimetic artificial networks would be advantageous alternatives since they can be designed to mimic biological recognition pathways, while being more robust and cost effective. In the field of controlled drug delivery, the ability to precisely tailor the transport properties of a given therapeutic molecule is fundamental to the success of a delivery device. Methods were developed to integrate biomimetic networks with silicon substrates at the micro-/nanoscale, enabling the fabrication of microdevice platforms that are based on silicon technologies. Biomimetic polymer networks specific for a target biomolecule were micropatterned onto silicon substrates and characterized by single and competitive fluorescent and confocal microscopy studies, SEM, and profilometry. Specifically, polymer networks that selectively recognize D-glucose among similar molecules via non-covalent complexation were micropatterned in fine dimensions. Novel copolymer networks containing poly(ethylene glycol) n dimethacrylate (where the molecular weight of the PEG, n = 44, 200, and 600) at various crosslinking percentages (30%, 67%, and 80%) and acrylamide as a functional monomer were synthesized in polar, aprotic solvent (dimethyl sulfoxide). These biomimetic polymer networks were effectively micropatterned and demonstrated to be specific for the target molecule. In particular, the binding and release kinetics were examined, and the relative binding affinities were analyzed.