Programmable microfluidic synthesis of spectrally encoded microspheres
Rachel E. Gerver, Rafael Gomez-Sjoberg, Brian C. Baxter, Kurt S. Thorn, Polly M. Fordyce, Camilo A. Diaz-Botia, Brett A. Helms and Joe L. DeRisiLab on a Chip 2012Abstract:
Spectrally encoded fluorescent beads are an attractive platform for assay miniaturization and multiplexing in the biological sciences. Here, we synthesize hydrophilic PEG–acrylate polymer beads encoded with lanthanide nanophosphors using a fully automated microfluidic synthesis device. These beads are encoded by including varying amounts of two lanthanide nanophosphors relative to a third reference nanophosphor to generate 24 distinct ratios. These codes differ by less than 3% from their target values and can be distinguished from each other with an error rate of <0.1%. The encoded bead synthesis strategy we have used is readily extensible to larger numbers of codes, potentially up to millions, providing a new platform technology for assay multiplexing.