1. A kit comprising: a) a first population of hydrogel beads, each hydrogel bead comprising: i) a polymerized monomer; ii) annexin V; and iii) an encapsulated nucleic acid; b) a second population of hydrogel beads, each hydrogel bead comprising: i) a polymerized monomer; ii) annexin V; but iii) lacking the encapsulated nucleic acid of the first population of hydrogel beads; and c) a third population of hydrogel beads, each hydrogel bead comprising: i) a polymerized monomer; but ii) lacking the annexin V of the first population of hydrogel beads and the second population of hydrogel beads; and iii) lacking the encapsulated nucleic acid of the first population of hydrogel beads; wherein the annexin V of the first and/or second population of hydrogel beads comprises SEQ ID NO: 102, and wherein the encapsulated nucleic acid of the first population of hydrogel beads binds to an intercalating dye selected from the group consisting of 7-aminoactinomycin D (7AAD) and propidium iodide.