@misc{10481/64549,
year = {2020},
url = {http://hdl.handle.net/10481/64549},
abstract = {Phase-resolved luminescence chemical sensors provide the analyte determination based
on the estimation of the luminescence lifetime. The lifetime is estimated from an analysis of the
amplitudes and/or phases of the excitation and emission signals at one or several modulation frequencies.
This requires recording both the excitation signal (used to modulate the light source) and the emission
signal (obtained from an optical transducer illuminated by the luminescent sensing phase). The excitation
signal is conventionally used as reference, in order to obtain the modulation factor (the ratio between the
emission and the excitation amplitudes) and/or the phase shift (the difference between the emission and
the excitation phases) at each modulation frequency, which are used to estimate the luminescence lifetime.
In this manuscript, we propose a new method providing the luminescence lifetimes (based either on
amplitudes or phases) using only the emission signal (i.e., omitting the excitation signal in the procedure).
We demonstrate that the luminescence lifetime can be derived from the emission signal when it contains
at least two harmonics, because in this case the amplitude and phase of one of the harmonics can be
used as reference. We present the theoretical formulation as well as an example of application to an
oxygen measuring system. The proposed self-referenced lifetime estimation provides two practical
advantages for luminescence chemical sensors. On one hand, it simplifies the instrument architecture,
since only one analog-to-digital converter (for the emission signal) is necessary. On the other hand,
the self-referenced estimation of the lifetime improves the robustness against degradation of the sensing
phase or variations in the optical coupling, which reduces the recalibration requirements when the
lifetimes are based on amplitudes.},
organization = {Spanish Ministry of Economy, Industry and Competitiveness 	
CTQ2017-88079-P
CTQ2014-53442-P
BES-2009-026919},
organization = {Spanish Ministry of Economy, Industry and Competitiveness (Torres Quevedo Grants) 	
PTQ-15-07922
PTQ-15-07912},
organization = {CEI BioTic Granada Campus 	
CEIbioTIC14-2015},
publisher = {MDPI},
keywords = {Chemical sensor},
keywords = {Luminescence spectroscopy},
keywords = {Multifrequency},
keywords = {Oxygen sensing},
keywords = {Frequency response},
keywords = {Quadrature detection},
keywords = {Self-referenced analysis},
title = {Self-Referenced Multifrequency Phase-Resolved Luminescence Spectroscopy},
doi = {10.3390/s20195482},
author = {Torre Vega, Ángel De La and Segura Luna, José Carlos and Fernández Sánchez, Jorge Fernando and Medina Rodríguez, Santiago},
}