Metal halide perovskite quantum dots for amphiprotic bio-imaging

Metal halide perovskite quantum dots (PQDs) have the prospective future in environment-dependent optic and optoelectronic applications because of its ability to survive and to hold their consistent light-emitting behavior in aqueous solution. However, due to the highly dynamic surface of PQDs which generates an unavoidable fragile bonding interaction, the existing materials exhibit the natural closeness in nonpolar solvent. But they have abnormal or unnatural phobic in aqueous solution. As a result, such nonpolarity-dependance becomes a barrier to be overcome for developing amphiprotic PQDs-based operation in aqueous solution. The objective of this review is to analyze the superiority of amphiprotic PQDs for one of the typical aqueous solution applications in in-vivo bio-imaging. The review focuses on polarity-induced deterioration, deterioration mitigation strategies, challenges involved in it and their future potentials. The development of amphiprotic PQDs will perfectly resolve the obstacles in using the PQDs in aqueous solution for the applications in the field of life science including cell imaging, tumor targeting imaging, single particle imaging, and in-vivo X-ray imaging.