The development of synthetic materials, which can serve as biomimetic receptors with performance equal to or better than that observed with antibodies is an ongoing challenge for scientists. Due to their chemical and physical properties and their potential for industrial scale manufacture, polymeric materials with bio-recognition features afford new opportunities as ‘artificial receptors’ in separation systems, sensors or bio-electronic devices, and as pharmaceutical and biomedical diagnostic screening tools [1], [2]. A significant constraint to the application of biomimetic polymers however has been the difficulty of their fabrication in the thin-film format with the required binding specificity.

This investigation describes the design, synthesis and application of molecularly imprinted polymers (MIPs) as patterned thin films, based on molecular modelling of functional monomer-template interactions and validation by NMR-spectroscopy. MIP thin film layers were prepared from solutions containing the template N-boc-L-phenylalanine and functional acrylic monomers at varying ratios with a cross-linker and initiator in a porogenic solvent. Using methacrylic acid, a first layer was spin-coated onto 3-(trimethoxysilyl)propyl methacrylate-functionalised silicon wafers and subsequently photo-polymerised. A 4-vinylpyridine-MIP thin film layer was then made by depositing the pre-polymerisation solution on top of the existing MIP layer. Photo-lithographic etching through a mask and removal of non-polymerised solution yielded a grid-patterned surface, in which two different MIPs alternated with dimensionality at the micro-meter scale. Selectivity differences between the two MIP surfaces towards the fluorescent template analogue N-dansyl-L-phenylalanine were documented in a side-by-side comparison using fluorescence microscopy.

This development provides a new avenue to implement a generic technology for the de novo design and synthesis of various biomimetic polymer surfaces, which can be integrated with advanced, micro-fluidic or multiplexing detection devices to provide the access to an additional class of array-based highly selective separation tools based on imprinted thin films for use in conjunction with high sensitivity detection methods (e.g. mass spectrometry, fluorescence, etc) of chemical or biological analytes.