Artificial Intelligence-Aided Massively Parallel Spectroscopy of Freely Diffusing Nanoscale Entities

0574423 - ÚIACH 2024 RIV US eng J - Journal Article
Hlaváček, Antonín - Uhrová, Kateřina - Weisová, Julie - Křivánková, Jana
Artificial Intelligence-Aided Massively Parallel Spectroscopy of Freely Diffusing Nanoscale Entities.
Analytical Chemistry. Roč. 95, č. 33 (2023), s. 12256-12263. ISSN 0003-2700. E-ISSN 1520-6882
Institutional support: RVO:68081715
Keywords : photon-upconversion * fluorescence cross-correlation spectroscopy * slitless spectroscopy * massively parallel spectroscopy
OECD category: Analytical chemistry
Impact factor: 7.4, year: 2022
Method of publishing: Open access
https://pubs.acs.org/doi/epdf/10.1021/acs.analchem.3c01043

Massively parallel spectroscopy (MPS) of many single nanoparticles in an aqueous dispersion is reported. As a model system, bioconjugated photon-upconversion nanoparticles (UCNPs) with a near-infrared excitation are prepared. The UCNPs are doped either with Tm3+ (emission 450 and 802 nm) or Er3+ (emission 554 and 660 nm). Particles emitting two emission wavelengths appear as double spots in the MPS images. The counting of double spots per MPS image is principally comparable to the cross-correlation amplitude in cross-correlation spectroscopy─both quantities can be used for quantification. However, MPS possesses much larger detection volumes and operates digitally, MPS can scan approximately 103× larger volume of dispersion in the same unit of time. These UCNPs are conjugated to biotinylated bovine serum albumin (Tm3+-doped) or streptavidin (Er3+-doped). MPS is correlated with an ensemble spectra measurement, and the limit of detection (1.6 fmol L–1) and the linearity range (4.8 fmol L–1 to 40 pmol L–1) for bioconjugated UCNPs are estimated. MPS is used for observing the bioaffinity clustering of bioconjugated UCNPs. This observation is correlated with a native electrophoresis and bioaffinity assay on a microtiter plate. A competitive MPS bioaffinity assay for biotin is developed and characterized with a limit of detection of 6.6 nmol L–1. MPS from complex biological matrices (cell cultivation medium) is performed without increasing background. The compatibility with polydimethylsiloxane microfluidics is proven by recording MPS from a 30 μm deep microfluidic channel. Because MPS is a new technique, the applications are only limited by the imagination and the persistence of the experimenter. Besides characterizing freely diffusing molecules and nanoparticles of diverse types, we speculate on homogeneous immunochemical assays and ratiometric nanosensors for high-throughput microfluidics. Additional imaging modalities like fluorescence, dark-field, and bright-field are of high interest.
Permanent Link: https://hdl.handle.net/11104/0344750