Patent ID: 8415173

Claim:
A method for making gel microdrops comprising, a) combining: i. monomers that can be polymerized to produce a polymer; ii. antibody-producing cells; iii. first reporter particles that emit a first optically detectable signal; and iv. second reporter particles that emit a second optically detectable signal that is distinguishable from the first optically detectable signal; b) making droplets of the product of step a), wherein the droplets contain an antibody producing cell, at least one of said first reporter particles, and at least one of said second reporter particles; and c) polymerizing the monomers of the droplets produced by step b) to produce gel microdrops that comprise: a polymer matrix, an antibody-producing cell that secretes antibody into said polymer matrix, at least one of said first reporter particles; and at least one of said second reporter particles; wherein, in said gel microdrops, said antibody-producing cell and said first and second reporter particles are encapsulated by said polymer matrix and wherein an alteration of said first or second optically detectable signal caused by selective binding interaction of said secreted antibody with one of said first or second reporter particles indicates that said secreted antibody is a selective binding agent.