Through-bond energy transfer cassettes for multicolor encoding.

Through-bond energy transfer (TBET) has been proposed as a versatile strategy to develop encoded microspheres. Together with the donor molecule, two TBET cassettes with high intramolecular TBET efficiencies (98% and 99%) and pseudo-Stokes shifts about 70 and 160 nm have been codoped into PS microspheres. Upon exclusive excitation at 480 nm, these microspheres emit simultaneously triple peaks at 512, 570, and 656 nm. Further confocal imaging and flow cytometric analysis demonstrates satisfactory performances of the new encoded microspheres.