Many conventional optical biosensing systems use a single responsive signal in the visible light region. This limits their practical applications, as the signal can be readily perturbed by various external environmental factors. Herein, a near-infrared (NIR)-based self-calibrating luminescence resonance energy transfer (LRET) system was developed for background-free detection of analytes in homogeneous sandwich-immunoassays. The inorganic LRET pair was comprised of NIR dual-emitting lanthanide-doped nanoparticles (LnNPs) as donors and NIR-absorbing LnNPs as acceptors, which showed a narrow absorption peak (800 nm) and long-term stability, enabling stable LRET with a built-in self-calibrating signal. Screened single-chain variable fragments (scFvs) were used as target avian influenza virus (AIV)-binding antibodies to increase the LRET efficiency in sandwich-immunoassays. The compact sensor platform successfully detected AIV nucleoproteins with a 0.38 pM limit of detection in buffer solution and 64 clinical samples. Hence, inorganic LnNP pairs may be effective for self-calibrating LRET systems in the background-free NIR region.
Bibliographical noteFunding Information:
This work was supported by the R&D Convergence Program of National Research Council of Science & Technology [grant number CAP-16-02-KIST/CRC-20-02-KIST ], Korea Institute of Science and Technology Institutional Program [grant number 2E3115A/2Z06270-20-137 ], KRIBB Research Initiative Program , and National Research Foundation of Korea (NRF) funded by the Korea government (MSIT) [grant number 2020R1A2C210111111 ].
© 2021 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Biomedical Engineering