Double-channel fluorimeter with pulsed excitation of advanced glycation end products in skin

A double-channel diagnostic fluorimeter operating in pulsed mode for in vivo assessment of the content of advanced glycation end products (AGEs) in skin by the autofluorescence integral intensity in the visible spectral region is developed. To excite the fluorescence we use a light-emitting diode with the peak wavelength 365 nm. A green light-emitting diode and an additional photodetection channel are intended to allow for the skin phototype of the patient. The fluorimeter analogue electronics comprises two photodetection channels based on silicon photodiodes. The accepted noise-suppressing circuitry solutions reduce the effect of sun and illumination lamp background light on the digital signal at the output of the 10-bit ADC to the one-bit level in both channels. The digital part of the fluorimeter is based on the Arduino platform. The software controls the operation modes of the fluorimeter, provides the quantitative processing of results, the diagnostic data storage and visualization. The experimental studies demonstrated the capabilities of revealing age-related changes in the skin.