Fluorescence Lifetime Spectroscopy of the Cornea using a Multichannel Scaler

Autor: D. R. Ramesh Babu, Sushma T, Sangly P. Srinivas, S. Amutha
Rok vydání: 2019
Předmět:
Zdroj: Materials Today: Proceedings. 10:32-37
ISSN: 2214-7853
DOI: 10.1016/j.matpr.2019.02.185
Popis: An interface based on Multichannel scaler (MCS; SR430; Stanford Research Systems, USA) has been tested for enabling fluorescence lifetime measurements of pO2-sensitive fluorophores with a custom-made confocal scanning microfluorometer (CSMF) for transcorneal pO2 measurements. SR430 served as a transient photon counter. A trigger pulse, coincident with the rising edge of an excitation pulse for fluorescence, was coupled to accumulate emission pulses detected by a photomultiplier tube (PMT; R928 HA, Hamamatsu, Inc). The pulse started the photon counting and segmented the photon count data into consecutive time bins (ranging from 1 up to 32k), the width of which could be varied from 5 ns to 10.486 ms. With no dead time between bins, photon counting with the fluorescence decay is seamless. Silica-bound Ruthenium phenanthroline, dispersed in silicone rubber, was employed as a fluorophore sensitive to pO2. The test interface for CSMF-MCS system showed sensitive pO2 measurements and hence is suitable to measure local pO2 at any depth across the cornea.
Databáze: OpenAIRE