Upconversion encoded microcarriers from electrospray microfluidics for multiplex bioassays

Encoded microcarriers are powerful tools in bioanalysis since they facilitate the detection of multiple targets during a single test. A current trend of developing encoded microcarriers is endowing them with features of easy coding/decoding, large coding capacity, and less restriction from usage conditions. Here, we presented novel upconversion nanoparticles (UCNPs)-encapsulated microcapsules derived from electrospray microfluidics as encoded microcarriers. The UCNPs offered a convenient optical coding/decoding mechanism; by encapsulating UCNPs into separate compartments of microcapsules via microfluidics, a large coding capacity was achieved. Most prominently, the unique anti-Stokes luminescent feature of the UCNPs made them less restricted from penetration depth of the excitation light. Benefiting from these merits, the microcarriers have demonstrated their value as barcodes for multiplex immunoassays. We believe this novel microcarrier could find potential applications in bioanalysis and biodiagnostic fields.