The ambient temperature synthesis and characterization of bile acid polymers

Room temperature polymerization of three naturally occurring bile acids, cholic, lithocholic and deoxycholic, was carried out using a mixture of diisopropyl carbodiimide (DIPC), and a 1:1 salt of dimethyl amino pyridine and p-toluenesulfonic acid (DMAP/PTSA). The corresponding polymers were characterized by IR, NMR, Thermal Analysis and X-ray diffraction. Molecular weights were calculated by gel permeation chromatography in the range 50,000-60,000, using polystyrene standards. The polymers were also characterized by mass spectrometry, using matrix assisted laser desorption ionization-time of flight, MALDI-TOF.