title: The in vitro biological properties of Mg-Zn-Sr alloy and superiority for preparation of biodegradable intestinal anastomosis rings.
abstract: BACKGROUND
  Magnesium (Mg) alloy is a metal-based biodegradable material that has received increasing attention in the field of clinical surgery, but it is currently seldom used in intestinal anastomosis. This study was conducted to comprehensively assess a ternary magnesium (Mg)-zinc (Zn)-strontium (Sr) alloy's biological superiorities as a preparation material for intestinal anastomosis ring.
  
  
  METHODS
  Mouse L-929 fibroblasts were cultured with Mg-Zn-Sr alloy extract and compared with both positive (0.64% phenol) and negative (original broth culture) controls. The cell morphology of different groups was examined using microscopy, and a cytotoxicity assessment was performed. Fresh anticoagulated human blood was mixed with Mg-Zn-Sr alloy extract and compared with both positive (distilled water) and negative (normal saline) controls. The absorbance of each sample at 570 nm was used to calculate the Mg-Zn-Sr alloy hemolysis ratio in order to test the Mg alloy's blood compatibility. Bacterial cultures of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus were added to Mg-Zn-Sr alloy block samples and compared with positive (Ceftazidime), negative (316LSS stainless steel), and blank controls. The broth cultures were sampled to compare their bacterial colony counts so as to evaluate the antibacterial properties of the Mg-Zn-Sr alloy. The Mg-Zn-Sr alloy was surface-coated with a layer of poly(lactic-co-glycolic acid) carrying everolimus. The surface morphology and degradability of the coating were examined so as to demonstrate feasibility of coating, which can release the drug evenly.
  
  
  RESULTS
  The experiments proved that Mg-Zn-Sr alloy has good biocompatible, antibacterial, and drug-loaded coating performances, which are lacking in existing intestinal anastomosis devices/materials.
  
  
  CONCLUSIONS
  The Mg-Zn-Sr alloy increases biocompatibility, and yields a safer and better therapeutic effect; therefore, it is a novel biomaterial that is feasible for use when preparing biodegradable intestinal anastomosis rings.
authors: National Hepatobiliary and Enteric Surgery Research Center, Xiangya Hospital, Central South University, Changsha, China (mainland).
authors: Ling
authors: L
authors: Liu
authors: National Hepatobiliary and Enteric Surgery Research Center, Xiangya Hospital, Central South University, Changsha, China (mainland).
authors: Nianfeng
authors: N
authors: Li
authors: State Key Laboratory for Powder Metallurgy, Central South University, Changsha, China (mainland).
authors: Ting
authors: T
authors: Lei
authors: Department of Mechanical Engineering, Hunan Industry Polytechnic, Changsha, China (mainland).
authors: Kaimo
authors: K
authors: Li
authors: Department of Mechanical Engineering, Hunan Industry Polytechnic, Changsha, China (mainland).
authors: Yangde
authors: Y
authors: Zhang
mesh_terms: D000328:Adult; D000497:Alloys / Q000494:pharmacology* / Q000633:toxicity; D000714:Anastomosis, Surgical; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001672:Biocompatible Materials / Q000494:pharmacology* / Q000633:toxicity; D016923:Cell Death / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000494:pharmacology; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000187:drug effects; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D007422:Intestines / Q000601:surgery*; D019344:Lactic Acid / Q000494:pharmacology; D008422:Materials Testing / Q000379:methods*; D051379:Mice; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D011100:Polyglycolic Acid / Q000494:pharmacology; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000497:Alloys; D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D020099:Coated Materials, Biocompatible; C573914:Mg-Zn-Sr alloy; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid