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Measuring the Human Ultra-Weak Photon Emission Distribution Using an Electron-Multiplying, Charge-Coupled Device as a
Fernando Ortega-Ojeda1,2, Matías Calcerrada3, Alejandro Ferrero4
1Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Multipurpose Building of Chemistry, University of Alcalá, Alcalá de Henares, 28871 Madrid, Spain. fernando.ortega@uah.es.
Sensors (Basel, Switzerland)
|April 13, 2018
Summary
Researchers developed a simple spectrometer to measure ultra-weak photon emission (UPE) from the human hand. This advancement in UPE measurement may offer insights into personal health states and reactive oxygen species (ROS) levels.
Area of Science:
- Biophysics
- Spectroscopy
- Biophotonics
Background:
- Ultra-weak photon emission (UPE) originates from living systems, primarily linked to oxidation reactions involving reactive oxygen species (ROS).
- Next-generation electron-multiplying CCD (EMCCD) sensors and liquid crystal tunable filters (LCTF) offer advanced capabilities for UPE detection.
Purpose of the Study:
- To explore the potential of a simple UPE spectrometer for measuring UPE from the human hand.
- To characterize the spectral distribution of UPE from human skin.
Main Methods:
- A straightforward UPE spectrometer setup was configured using a dark box, LCTF as a monochromator, and an EMCCD sensor.
- Human hand UPE was measured at selected wavelengths (400-700 nm) under controlled conditions.
- Data processing involved filtering spurious signals and subtracting dark signals to obtain UPE spectra.
Main Results:
- The human hand UPE spectrum exhibited a peak emission of approximately 880 photons at 500 nm.
- The observed spectral shape and range (420-570 nm, extending to 260-800 nm) align with previous UPE research.
- UPE intensity ranged from 1 to 1000 photons s-1 cm-2.
Conclusions:
- Measuring the spectral distribution of UPE, rather than just total intensity, represents a significant advancement.
- This technique may provide novel insights into an individual's physiological state and their relationship with ROS.
- Future developments in sensor technology could enable portable UPE measurement systems.
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