Multicolor upconverted luminescence-encoded superparticles via controlling self-assembly based on hydrophobic lanthanide-doped NaYF4 nanocrystals

We demonstrated the conceptual advantage of encoded superparticles (SPs) based on the upconverted luminescence (UCL) spectral signature. In this research, mass fabrication of UCL-encoded SPs has been achieved by employing a facile, robust, and low-cost self-assembly in microemulsion droplets, which offered a convenient, straightforward, and reproducible technique. The barcode information can be predicted and designed by controlling lanthanide (Ln) composition, dopant concentration, and mass content inside SPs. Furthermore, the SPs were encapsulated with an amphiphilic polymer poly(maleic anhydride-alt-1-octadecene) (PMAO), which not only enhances the stability of the UCL-encoded SPs but also provides the biocompatibility for immobilization of biomolecules. In addition, their surface bioactivity was investigated by using protein immunoassay, which indicates the potential application of the UCL-encoded SPs in biodetection and biomedicine.