RT Journal Article
T1 Influence of excitation pulse duration on the efficiency of upconversion nanoparticle-based FRET
A1 Casillas Ruibio, Alejandro
A1 Hamraoui, Khouloud
A1 Méndez González, Diego
A1 Laurenti, Marco
A1 Rubio Retama, Benito Jorge
A1 Gómez Calderón, Óscar
A1 Melle Hernández, Sonia
AB Accurate and reliable quantification of Förster Resonance Energy Transfer (FRET) is essential for the development of sensitive upconverting nanoparticle (UCNP)-based biosensors. While lifetime-based FRET measurements are generally considered robust, excitation conditions can significantly bias observed efficiencies. Here, we investigate how excitation pulse width and power influence lifetime-derived FRET efficiency in core–shell β-NaYF4:Yb0.2@NaYF4:Yb0.2,Er0.02 UCNPs functionalized with Cy3 dyes. Time-resolved upconversion luminescence (UCL) measurements reveal that apparent FRET efficiencies decrease with increasing excitation pulse duration and power. These variations stem from excitation-induced changes in the UCL lifetime, arising from the complex dynamics that accompany the upconversion emission process. A dynamic rate equation model reproduces the experimental trends, confirming that excitation parameters alter emissive state kinetics and thus bias lifetime-based FRET measurements. Our findings identify excitation conditions as a hidden variable in UCNP-FRET experiments and underscore the need for standardized measurement protocols.
PB Royal Society of Chemistry
SN 2040-3364
YR 2025
FD 2025
LK https://hdl.handle.net/20.500.14352/131487
UL https://hdl.handle.net/20.500.14352/131487
LA eng
NO Casillas-Rubio, Alejandro, et al. «Influence of Excitation Pulse Duration on the Efficiency of Upconversion Nanoparticle-Based FRET». Nanoscale, vol. 17, n.o 31, 2025, pp. 18173-84. DOI.org (Crossref), https://doi.org/10.1039/D5NR01779C.
NO 2024 Acuerdos transformativos CRUE. This work was supported by Ministerio de Ciencia e Innovación (PID2023-150645OA-I00, PID2021-122806OB-I00, PID2021-123318OB-I00 and TED2021-132317B-I00), Fundación Alonso (2024/0041), and Comunidad de Madrid (P2022/ BMD-7403 RENIM-CM). A. C. R. thanks UCM-Santander for a predoctoral contract (CT15/23).Datos de investigación en: https://hdl.handle.net/20.500.14352/120840
NO Ministerio de Ciencia e Innovación (España)
NO Comunidad de Madrid
NO Universidad Complutense de Madrid
NO Banco Santander
NO Fundación Alonso
DS Docta Complutense
RD 22 mar 2026