Luminescence phenomena of biodegradable photoluminescent poly(diol citrates)

The possible origin of luminescent properties of biodegradable photoluminescent polyesters (BPLPs) has been revealed by isolation and identification of luminescent agent from the hydrolyzate of BPLP. Elemental analysis, ESI-MS, 1H, 13C, 2D HSQC and COSY NMR spectra confirmed the chemical structure as 5-oxo-2,3-dihydro-5H-[1,3]thiazolo[3,2-a]pyridine-3,7-dicarboxylic acid (TPA).