SmartPAN: In vitro and in vivo proof-of-safety assessments for an intra-operative predictive indicator of postoperative pancreatic fistula

Pancreatic surgery is complicated by untreated fluid leakage, but no tenable techniques exist to detect and close leakage sites during surgery. A novel hydrogel called SmartPAN has been developed to meet this need and is here assessed for safety before trials on human patients. First, resazurin assays were used to test the cytotoxic effects of SmartPAN's active bromothymol blue (BTB) indicator and its solution of phosphate-buffered saline (PBS) on normal (HPDE: human pancreatic duct epithelial) or carcinomic (FAMPAC) human pancreatic cells. Cells incubated with BTB showed no significant reduction in cell viability below threshold safety levels. However, PBS had a mild cytotoxic effect on FAMPAC cells. Second, SmartPAN's pathological effects were evaluated in vivo by applying 4-ml SmartPAN to a porcine (Sus scrofa domesticus) model of pancreatic resection. There were no significant differences in macroscopic and microscopic pathologies between pigs treated with SmartPAN or saline. Third, measurements using HPLC-MS/MS demonstrate that BTB does not cross into the bloodstream and was eliminated from the body within 2 days of surgery. Overall, SmartPAN appears safe in the short term and ready for first-in-human trials because its components are either biocompatible or quickly neutralized by dilution and drainage.