Fabrication of molecularly imprinted polymer microarray on a chip by mid-infrared laser pulse initiated polymerisation

The possibility to assess several functional polymeric materials in parallel in a microchip format could find a wide range of applications in sensing, combinatorial and high-throughput screening. However several factors, inherent to the nature of material polymerisation have limited such development.We here report an innovative fabrication approach for the elaboration of polymer microarrays bearing polymer dots typically 300 μm in diameter fabricated in situ on a glass cover slip via CO2 laser pulse initiated polymerisation, as well as initial results on the identification of a suitable monomer composition for the molecular imprinting of dansyl-l-phenylalanine as a proof-of-concept example. A combination of methacrylic acid and 2-vinylpyridine showed the largest affinity to dansyl-l-phenylalanine which agreed with the existing literature and the results were further confirmed by HPLC.Finally, a sensor chip bearing both non-imprinted as well as imprinted polymers was also prepared in order to prove the suitability of this fabrication approach for the elaboration of MIP based sensors. The assay consisted in a simple dip-and-read step and the sensing system was able to discriminate between the l and d enantiomers of dansylphenylalanine with an imprinting factor of 1.6.