Antibody discovery can benefit from techniques to screen antibody-secreting cells (ASCs) at scale for the binding and functionality of a diverse set of secreted antibodies. Previously, we demonstrated the use of cavity-containing hydrogel microparticles (nanovials) coated with a single affinity agent, biotin, to capture and identify ASCs secreting antibodies against a recombinant antigen bound to the nanovial through biotin-streptavidin linkages. However, rapidly secreted antibodies from unbound cells or cells in adjacent nanovials can cause crosstalk leading to background signal. Earlier efforts address this by localizing capture sites to the nanovial cavity, emulsifying nanovials, or short secretion times to limit secreted antibodies from binding to neighboring nanovials. Here, we demonstrate a method to functionalize nanovials with moieties that impart orthogonal reactivity, enabling conjugation of cell capture antibodies and antigens at different times. We show that by using a strained alkyne moiety to attach cell-capture antibodies