Abstract:

Gastrointestinal tumors are common malignant tumors in the digestive tract, of which gastric cancer is the third leading cause of cancer death and colorectal cancer is the fourth most deadly cancer. Nowadays, surgical resection remains to be one of the main measures for treating digestive tract tumors, and gastrointestinal anastomosis remains to be a key step in gastrointestinal surgery. Mg and its alloys have great potentials to be used for gastrointestinal anastomosis as anastomotic nail materials due to their biodegradability, good mechanical properties and biocompatibility. In this study, Mg-2Zn-0.5Nd (ZN20) alloy fine wires showed great potential as surgical staples. When we performed in vitro corrosion experiments, drainage fluid was collected from different parts of the patient's abdominal cavity after surgery for the first time to replace the traditional simulation fluid and to more realistically simulate the microenvironment required by the anastomotic nail. ZN20 alloy has an ultimate tensile strength of 256 MPa, an elongation rate of 12.56%, a tensile force in anastomosis of 16.8 N, and a rupture pressure after anastomosis at 17 kPa, which means that a sufficient mechanical support was provided after anastomosis. The statistical analysis and histopathological analysis of biochemical tests indicate that ZN20 alloy has no adverse effect on the normal metabolism of liver, kidney and body, but has superior biocompatibility and biosafety. This work confirms that ZN20 possesses a great application potential in the clinical field as a new type of gastrointestinal anastomotic nail material.

Key words: Magnesium alloy, Gastrointestinal tumor, Absorbable, Degradation rate