New application of acridine orange to study biophysics of exocytotic processes in cell

Abstract

Mucus secretion is the first-line of defence against the barrage of irritants inhaled into human lungs, but abnormally thick and viscous mucus results in many respiratory diseases. Investigation of processes underlying mucus pathology is hampered, in part, by lack of appropriate experimental tools for labeling and studying mucin granule secretion from live cells with high sensitivity and temporal resolution. Fluorescence spectra and fluorescence lifetime of AO measurements reveal significant changes due to aggregation, and this properties can be useful for determination of mucus expansion. In this report I present original spectroscopic properties of acridine orange (AO) which could be utilized to study granule release and mucin swelling with novel fluorescence imaging approaches. To explore fluorescent properties we measured the quantum yield and extinction coefficient and lifetimes