Biocompatibility Evaluation of EDTA and Chitosan Nanoparticles Gel Forms: In Vivo Histopathological Study

Objectives: The purpose of this study was to evaluate and compare biocompatibility of gel form chelating agents [EDTA and chitosan nanoparticles (NPS)] after implantation of polyethylene tubes in rats. Materials and methods: Twenty albino rats were included in this study. Three horizontal incisions were performed on dorsal surface of each rat to receive three polyethylene tubes as subcutaneous implants; two of them filled with tested materials and one empty tube served as control. After 2 and 4 weeks of subcutaneous implantation, 10 rats were sacrificed and implanted polyethylene tubes with surrounding tissues were dissected with 1 cm safety margin. The specimens were submitted to histological preparation and stained with hematoxylin and eosin then investigated using light microscope. The number of inflammatory cells were assessed and statistically compared by One-way analysis of variance (ANOVA), followed by the post hoc Tukey's test (P<0.05). Results: After 2 and 4 weeks, the inflammatory reaction mean values of EDTA gel were higher than chitosan NPS gel with a significant difference (P<0.05). EDTA gel induced a severe inflammatory response higher than the control group with a significant difference (P<0.05). However, chitosan NPS gel induced mild inflammatory reaction insignificantly different with control group (P > 0.05). After 4 weeks of implantation, the severity of inflammatory cell infiltration was decreased in all groups. Conclusions: All tested materials produced inflammatory reactions. The tissue inflammatory reaction induced by tested materials showed a gradual reduction with time. 0.2% chitosan NPS gel demonstrated superior biocompatibility compared with EDTA gel.