Preclinical evaluation of medical devices (prototype products) offers the opportunity to investigate and study the intended use of device materials. Preclinical evaluation programs are designed to determine the efficacy, safety, and biocompatibility of biomaterials, prostheses, and medical devices. The purpose of safety testing is to determine if a material presents potential harm to the human; it evaluates the interaction of the material with the in vivo environment and determines the effect of the host on the implant. Preclinical evaluation is the determination of the ability of the prototype product to perform with appropriate host response in a specific application, considered from the perspective of human clinical use. Therefore, preclinical data should include materials science and engineering, biology, biochemistry, medicine, host reactions and their evaluation, the testing of biomaterials, and the degradation of materials in a biological environment.
Animal ; Carcinogenicity Tests ; Equipment and Supplies*/adverse effects ; Hemolysis ; Human ; Pyrogens/toxicity ; Sterilization

To detect the toxic reaction degree for sheep acellular dermal matrix (ADM) in vivo or vitro by using hemolytic, pyrogen and cell-cytotoxic reaction experiments, respectively.
 Methods: Leach liquor of cross-linked and non-cross-linked sheep ADMs were set for cross-linked group and non-cross-linked group, respectively, with a positive control group (10 mL sterile water for injection in test tube) and a negative control group (10 mL 0.9% sodium chloride solution in test tube). The supernatants were obtained from each group and were measured for the absorbance. The hemolysis degree was calculated; 16 New-Zealand rabbits were selected and then divided into 4 groups, A, B, C and D group. The leach liquor of cross-linked and non-cross-linked sheep ADMs were injected into bodies of the 6 New-Zealand rabbits in the A and B groups, and then the body temperatures were measured in every half hour after injection, 6 times in total. The value of highest temperature among 6 measurements minus the normal temperature was the fever degree for the body temperature. Based on these fever degree, the criterion of biological pyrogen reaction for sheep ADM pyrogen experiment was evaluated; the mice fibroblasts were collected during logarithmic phase and were cultured in the nutrient medium containing sheep ADM leach liquor with different density. The absorbance was measured to evaluate relative growth rate for fibroblast.
 Results: The hemolysis degree for the group A and B are less than 5%. The summary of fever degree for New-Zealand rabbits were lower than 1.8 ℃. MTT experiment showed that the toxicity of 10%-90% or 100% leach liquor nutrient medium with sheep ADM for the mice fibroblast is at level 1 or level 2. There was no significant difference between leach liquor of cross-linked and non-cross-linked sheep ADMs (P>0.05). The effects on relative growth rate for mice fibroblasts were minor. 
 Conclusion: The hemolytic and pyrogen reactions for the sheep ADMs embedded in New-Zealand rabbit were within the evaluation criterion, and the effects on vitality and growth rate for the fibroblast were not significant.
Acellular Dermis ; adverse effects ; Animals ; Cell Culture Techniques ; Culture Media ; adverse effects ; toxicity ; Fibroblasts ; drug effects ; Growth Inhibitors ; pharmacology ; Hemolysis ; drug effects ; In Vitro Techniques ; Mice ; Pyrogens ; pharmacology ; Rabbits ; Sheep