Solid-phase oligonucleotide synthesis and flow cytometric analysis with microspheres encoded with covalently attached fluorophores

A novel combinatorial approach to synthesize oligonucleotides on fluorescen tly encoded microspheres based on flow sorting and segmental solid-phase sy nthesis is described. BODIPY dyes were covalently attached to polystyrene ( 8.8 mu m, 55% DVB) microsphere particles to generate four fluorescently enc oded sets. 20-mer oligonucleotide sequences can be synthesized on these mic rospheres with yields comparable to conventional CPG supports (80% overall yield, average stepwise yield = 99%). The concept of segmental solid-phase synthesis by flow sorting was demonstrated by synthesizing unique 20-mer ol igonucleotide sequences on each of four fluorescently encoded microsphere s ets by including a flow sorting step (after first eight base additions) and flow cytometric detection of sequences synthesized on each microsphere set by hybridization with fluorescently labeled complementary sequence.