BACKGROUND: Acellular dermal matrix has the disadvantages of natural materials such as rapid and unregulated degradation and poor mechanical properties. It is a commonly used improvement measure for glutaraldehyde cross-linking modification. However, glutaraldehyde itself has a high cytotoxicity, which affects the biocompatibility of acellular dermal matrix. OBJECTIVE: To improve the biocompatibility of the glutaraldehyde cross-linked acellular dermal matrix by using glycine to neutralize remaining aldehyde groups. METHODS: As an experimental group, the acellular porcine dermal matrix was cross-linked by glutaraldehyde and then neutralized by glycine. The control group was that acellular dermal matrix which was cross-linked by glutaraldehyde but not neutralized by glycine. The residual exogenous DNA of materials of the experimental group was detected by DNA kit. The uncrosslinked acellular porcine dermal matrix and the samples of the experimental group and control group were immersed in collagenase solution to observe degradation performance. Mouse fibroblasts were cultured in culture medium, high-density polyethylene extracts, sample extracts of the experimental group and control group, respectively. After 24 hours of culture, cell proliferation rate was determined by MTT assay. Mouse osteoblasts were seeded onto the membrane surface of the experimental group and the control group and cultured for 7 days. The cell status was observed under confocal microscope. The membrane materials of the experimental group and the control group were respectively implanted beneath the skin of New Zealand rabbits, and the samples with surrounding tissues were removed at 2 weeks later for hematoxylin-eosin staining observation. RESULTS AND CONCLUSION: (1) The amount of DNA residues in samples of the experimental group was (3.12±0.7) μg/g. (2) After enzymolysis for 8 hours, there was no significant difference in the weight loss rate of samples between the experimental group and the control group (18%-21%), while the weight loss rate of samples without glutaraldehyde cross-linking was 100%. (3) After culture for 24 hours, the proliferation rates of fibroblasts cultured in the leaching liquor of samples in the experimental and the control groups were 98.1% and 91.3%, respectively. The results showed the level of cytotoxicity was both grade 1. (4) Osteoblasts spread evenly and multiplied vigorously on the membrane surface in the experimental group, while curled up and were few in number in the control group. (5) After membranes implanted beneath the skin of the rabbit for 2 weeks, tissues around the implant site of the experimental group showed a slight inflammatory response, while those in the control group showed severe inflammatory response. (6) These results suggest that glycine neutralizing remaining aldehyde groups could improve the biocompatibility of glutaraldehyde cross-linked acellular dermal matrix material on the premise of guaranteeing the degradation performance. [ABSTRACT FROM AUTHOR]