BACKGROUND: Staphylococci inhibitor, RNAⅢ inhibiting peptide, has been firstly synthesized in China, while RNAIII inhibiting peptide/bioinspired phosphorylcholine-based cytomembrane coating (RIP/PC) has been also prepared.OBJECTIVE: To evaluate the blood compatibility of RIP/PC.DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed at Institute of Clinical Pharmacologic Research and Medical Animal Experimental Center of General Hospital of Chinese PLA from October 2005 to October 2007.MATERIALS: A total of 30 healthy adult New Zealand rabbits were provided by Animal Experimental Center of General Hospital of Chinese PLA.METHODS: The 316L stainless steel was dip into a mixture of 5 g/L quaternionic copolymer tetrahydrpfuran and 10% RNAⅢ inhibiting peptide to obtain stable polymer coating, which was extracted at density of 1 cm~2/mL in saline at 37 ℃ for 72 hours to get 100% eluent. The same volume of saline was added to make 50% eluent. The effects of RIP/PC on leukocytes, eryfhrocytes,and blood platelet of rabbits were detected via measuring prothrombin time and activated thrombin time during hemolysis test,hemagglutinatin test, and blood platelet aggregation test.MAIN OUTCOME MEASURES: Hemolytic ratio of erythrocytes, clotting time, prothrombin time, activated thrombin time, amounts of leukocytes, erythrocytes, and blood platelet, as well as blood platelet aggregation.RESULTS: Hemolysis test showed that the hemolytic ratio was 3.08% and 1.88% of 100% and 50% eluent, respectively; both the hemolytic ratios were < 5%, suggesting being coincidence with hemolytic requests of biological materials. The hemagglutinatin test showed that both 100% and 50% eluent did not have any effect on clotting time, prothrombin time, activated thrombin time,amounts of leukocytes, erythrocytes, and blood platelet, as well as blood platelet aggregation.CONCLUSION: The firstly synthesized RIP/PC has a good biocompatibility.