The present article describes preparation, optimization, and characterization of pectin grafted polyvinylpyrrolidone hydrogels followed by controllable theophylline drug release. The gels were prepared in the presence of N,N'-methylenebisacrylamide (MBAA) crosslinker and ceric ammonium nitrate (CAN) initiator under N-2 atmosphere. Optimum conditions, in terms of percent of grafting (%G), were determined as follows: Pectin = 1.0 g, [NVP] = 2.81 mM, [MBAA] = 0.65 mM, [CAN] = 0.073 mM, polymerization temperature = 30 degrees C and time = 4.0 hrs. Hydrogels were characterized by FTIR, TGA, DSC, XRD, and SEM. In vitro controllable release of theophylline model drug was studied using different N-vinyl-pyrrolidone monomer to MBAA crosslinker ratio (i.e., [NVP]/[MBAA] ratios) and different polymerization temperatures at two pH values, namely 5.5 and 7.4. The optimum conditions for colon-targeted vehicles that could provide the least theophylline release at pH 5.5, and the most theophylline release at pH 7.4, were as follows: [NVPI/IMBAA] = 4.33, polymerization temperature = 10 degrees C and %G = 62.2. Such promising hydrogel characteristics may play the key role in many future drug release implementations. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: 1945-1954, 2010