Time-resolved luminescent biosensing based on inorganic lanthanide-doped nanoprobes

Abstract

Time-resolved (TR) photoluminescence (PL) biosensing has been widely adopted in many research and medical institutions. However, commercial molecular TRPL bioprobes like lanthanide (Ln³⁺)-chelates suffer from poor photochemical stability and long-term toxicity. Inorganic Ln³⁺-doped nanocrystals (NCs), owing to their superior physicochemical properties over Ln³⁺-chelates, are regarded as a new generation of luminescent nanoprobes for TRPL biosensing. The long-lived PL of Ln³⁺-doped NCs combined with the TRPL technique is able to completely suppress the interference of the short-lived background, resulting in a background-free signal and therefore a remarkable sensitivity for biosensing. In this feature article, we summarize the latest advancements in inorganic Ln³⁺-doped NCs as TRPL nano-bioprobes from their fundamental optical properties to their potential applications for ultrasensitive biodetection and high-resolution bioimaging. Future efforts towards the commercialization of these nanoprobes are also proposed.