A facile method for coding and labeling assays on polystyrene beads with differently colored luminescent nanocrystals

The present paper describes a new, facile and fast technique that can be used to incorporate CdSe/ZnS core/shell nanocrystals into polystyrene beads. The nanocrystals were immobilized within the polymer beads by demixing two nonmiscible solvents. The resulting beads were bright, homogeneously coded, and did not show any surface texture or photobleaching under application-relevant conditions. The beads were subsequently used on a model streptavidin-biotin binding system in order to demonstrate the applicability of the technique to enzyme-linked assays and multiplexing applications.