A Versatile Photoinduced Electron Transfer‐Based Upconversion Fluorescent Biosensing Platform for the Detection of Disease Biomarkers and Nerve Agent

Abstract

Upconversion nanoparticles (UCNPs) have emerged to be a new family of fluorescent probes for bioanalytical applications. In a typical design, the UCNPs act as the energy donors in a fluorescence resonance energy transfer (FRET) system, in which the target molecules mediate the energy transfer from the UCNPs to the acceptors, and their quantity information is consequently converted into the “on‐off” upconverting signals for readout. However, each UCNP contains thousands of emitting center ions and most of them are beyond the FRET critical distance, which hinders the fluorescence energy transfer efficiency, resulting in a low signal‐to‐background ratio (SBR). Herein, a new design is presented in which the energy of UCNPs is transferred to the o‐quinones on their surface via the photoinduced electron transfer (PET) mechanism. In this system, the quenching efficiency of UCNPs' fluorescence can be up to 94.73%, providing a high SBR. The performance of the PET‐based design is systematically testified, and the high‐sensitivity detection of disease biomarkers (tyrosinase and alkaline phosphatase) is demonstrated. Moreover, this UCNP‐PET platform is also capable of sensing the simulant of nerve agent sarin. This work will pave new ways to the design of UCNP‐based platforms toward bioanalytical applications.

A March to Shape Optical Artificial Olfactory System toward Ultrasensitive Detection of Improvised Explosives

“…Reproduced with permission. [ 173 ] Copyright 2019, Wiley‐VCH. d) Modification strategy of quantum dots.…”

“…It is hoped to achieve highly sensitive and anti-interference IEs detection by modifying its surface ligand to act as an energy donor or electron donor and combining with specific recognition groups (Figure 11c). [173] Quantum dots have the properties of stable luminescence and easy surface modification, which can be easily connected with recognition groups to realize optical chemical detection. [174,175] The recognition molecules of IEs were modified on quantum dots and the energy levels were regulated by functional ligands.…”

Lanthanide-Doped Upconversion Nanoparticles Meet the Needs for Cutting-Edge Bioapplications: Recent Progress and Perspectives

“…As a proof-of-concept, this platform was used for the sensitive intracellular tracking and visualization of microRNA-21. Li and co-workers established a versatile UCNPs-PET platform with the luminescence quenching efficiency as high as 94.73%, which thus possess a high signal-to-background ratio (SBR) for sensitive detection of tyrosinase and alkaline phosphatase, as well as nerve agent simulant . Aside from the disease biomarker recognition, UCNPs-based platforms for disease pathogen analysis have also been recently reported.…”

“…Li and co-workers established a versatile UCNPs-PET platform with the luminescence quenching efficiency as high as 94.73%, which thus possess a high signal-to-background ratio (SBR) for sensitive detection of tyrosinase and alkaline phosphatase, as well as nerve agent simulant. 77 Aside from the disease biomarker recognition, UCNPs-based platforms for disease pathogen analysis have also been recently reported. Zhou and co-workers designed a series of special upconversion nanoparticles (τ λ -UCNPs) with different luminescence emissions and decay lifetimes, which can construct more than 10 5 codes through color/lifetime binary strategy.…”

Nanoparticle Tracking Analysis-Based In Vitro Detection of Critical Biomarkers

“…In recent years, the unique properties of nanoparticles have led to prosperity in nanoparticle-based in vitro assays of critical biomarkers. , These assays can be realized by monitoring the target-induced responses of the nanoparticles, including fluorescence intensity, − colorimetric response, − Raman scattering, − magnetic resonance, − and computed tomography signal . Although the nanoparticle-based biosensing methods have their own advantages, their versatility and prevalence remain hampered.…”