A new pH-responsive polymer (TKP-AA-PAA) was synthesized from the combination of tamarind kernel powder (TKP), acrylic acid (AA), and polyamidoamine (PAA) which was utilized for controlled release of 5-aminosalicylic acid (5-ASA) in buffer medium. The network structure of TKP-AA-PAA was obtained by irradiating the mixture of TKP, AA, and PAA in different proportion in presence of 2,2-dimethoxy-2-phenyl acetophenone as a photoinitiator. The dynamic and equilibrium swelling properties of the polymeric materials were studied as a function of pH and time in different buffer solutions similar to that of gastric and intestinal fluids. The controlled release kinetics of 5-ASA in simulated body fluid showed a Fickian diffusion behavior.