Advances in Quantum Sensing With Fluorescent Nanoparticles

Abstract

Rapid advancements in quantum sensing, nanophotonics, and quantum optics have resulted in the development of innovative techniques and materials addressing biomedical and environmental challenges. This study focuses on fluorescent nanoparticles, notably upconversion nanoparticles (UCNPs), nitrogen-vacancy nanodiamonds (NVNDs), and gold nanoparticles (AuNPs), which exhibit unique optical properties beneficial to quantum sensing and nanophotonics. The study also explores the role of Förster resonance energy transfer (FRET) in quantum sens-ing. The 2,2’-[ethylenebis(oxy)] bisacetic acid (EBAA) approach, a method of synthesizing hydrophilic UCNPs that surpasses traditional techniques due to its enhanced stability, biocompatibility, and optical properties, is examined in detail. The characteristics and potential applications of hydrophilic UCNPs produced via EBAA in quantum sensing, nanophotonics, and quantum optics are evaluated, with a focus on drug delivery, bioimaging, and solar cells. The study also compares EBAA with other surface modification methods and discusses future prospects and challenges for hydrophilic UCNPs. This dissertation innovates a quantum optics-based strategy for SARS-CoV-2 cDNA detection using upconversion and gold nanoparticles. Utilizing FRET coupling between UCNPs and AuNPs, a sensitive and specific detection method with a 632 pM detection threshold is designed. The results emphasize the potential of FRET-coupled UCNPs and AuNPs to enhance diagnostics and research in quantum sensing and nanophotonics. The research underscores the necessity of novel methodologies and materials to expand the applications of fluorescent nanoparticles in various physics domains. The ultimate objective is to demonstrate how integrating advancements in hydrophilic UCNPs synthesis with quantum optics-based detection techniques can amplify the versatility of these nanoparticles for future research in nanophotonics and quantum sensing.