Biocompatible and biodegradable hydrogels based on carboxymethylcellulose (CMC) and poly(ethylene glycol) (PEG) were prepared as physical barriers for preventing surgical adhesions. These interpolymeric hydrogels were synthesized by a gamma-irradiation crosslinking technique. Sections (1.5 cm X 1.5 cm) of the cecal serosa and an adjacent abdominal wall were abraded with a bone burr until the serosal surface was disrupted and hemorrhagic but not perforated, and the serosa of the cecum was sutured to the abdominal wall 5 mm away from the injured site. The denuded cecum was covered with either CMC/PEG hydrogels or a solution from a CMC/PEG hydrogel. A control rat serosa was not covered. Two weeks later, the rats were killed, and the adhesions were scored on a 0-5 scale. No treatment showed a significantly higher incidence of adhesions than the CMC/PEG hydrogels or solutions from the CMC/PEG hydrogels. This study demonstrated that CMC/ PEG hydrogels could prevent intra-abdominal adhesion in a rat model. (c) 2005 Wiley Periodicals, Inc.