Development of raman mapping technique for multiplex bar-encoded polymer resins

Bar coded resins (BCR) are widely used in bioassays as a solid immune support, and spectroscopically classified for bio-recognition. A significant step forward is classification of several BCR in a single measurement, for multiplex readout in a bead-based array. In this study, characteristically unique Raman polymer microbeads were synthesized, and identified based on Raman spectroscopic analysis as well as Raman mapping with a nanoscale resolution. Spectroscopically active monomers were utilized for the synthesis of four different surface functionalized monodisperse polymer microbeads by dispersion polymerization (size tilde 1.5 to 2mum), namely, poly(styrene-co-acrylic acid), poly(4tetrabutylstyrene-co-acrylic acid), poly(4methylstyrene-co-acrylic acid) and poly(glycidyl methacrylate-co-acrylic acid). Raman false colored mapping with nanoscale resolution was used for multiplex microbeads readout with the help of narrow spectral bands by selected spectral region and multivariate analysis technique. This signifies the ability to use BCR as a support with the traditional encoders to enhance combinatorial chemistry and multiplex library in suspension bioassay.