Ingenious nanoprobes in bioassays

This article has a special focus on the broad range of innovative nanoprobes for signal amplification and new generations of bioassays. Advances in functionalizing gold nanoparticles with oligonucleotides speed up the development of a series of new nucleic acid assays. A biobarcode assay allows signal amplification by utilizing antibody-coated magnetic beads to concentrate the analytes and antibody-coated gold nanoparticle probes to carry a large number of oligonucleotides. Novel signal-amplification technologies, based on either new classes of nanoprobes consisting of releasable fluorophores or with aggregation-induced emission features, can also improve the sensitivity of bioassays. Advances in synthesis and biofunctionalization of quantum dots with unique properties have generated increasingly widespread applications in DNA sorting, multiplexing bioassays and fluorescence resonance energy transfer-based sensing. Ingenious nanoprobes in bioassays can offer PCR-like sensitivity, high selectivity, capacity for massive multiplexing, time efficiency and, most importantly, the ability to be performed at the point- of-care.