Synthesis and characterization of new biodegradable fluorescing poly(amide-anhydrides)

Biodegradable/alternate/poly(amide-anhydrides, [-C(O)PhNHC(O) (CH2)(n)C(O)O -](x), were synthesized by melt polycondensation, where n was 2, 3 or 4. Th e polymers have been characterized by NMR, DSC, wide-angle X-ray diffractom etry and fluorometry. All the polymers are amorphous and their Tg ranges fr om 60 to 80 degreesC. Poly(p- (carboxyethylformamido)benzoic anhydride) (PC EFB) as a film or in solution in chloroform can emit strong fluorescence, w hich was not observed for the other two polyanhydrides (n =3, 4). The maxim um emission wavelength varies with the excitation wavelength, 480 and 520 n m at the excitation wavelength of 470 nm, and 430 nm at 356 nm. In addition , the fluorescence intensities increase linearly with the molecular weight of PCEFB. Such inherent fluorescing properties of PCEFB, together with its biodegradability, make the polymer a potential visible matrix for drug deli very. (C) 2001 Society of Chemical Industry.