An experimental study for chemical characterization of artificial anterior cruciate ligament with coated chitosan as biomaterial

Abstract

Abstract The importance and aim of this experimental study is that raw artificial anterior cruciate ligament samples were produced with various 3-D braiding constructions with various technical yarns using the 3-D braiding method. Later, it is aimed to determine the chemical bond changes between raw samples with ethylene oxide (EtO) sterilization and bio-chemical finishing samples by applying padding process and EtO sterilization processes for all samples with 3-D braiding structures, due to the cross-linking of biocompatible chitosan (CHI) with biological cross-linker glutaraldehyde (GA). The importance of this experimental study is that it is the first experimental chemical analysis in this field in the world scientific study. Padding and EtO sterilization processes were applied on all samples and compared to various technical yarns with 3-D braiding structures thanks to biocompatible CHI. Chemical analysis was interpreted for all samples. It was determined that the applied temperature, concentration, pH, yarn types, characteristic bonds in the chemical structure of the technical yarns, applied bio-chemical finishing process and EtO sterilization had effect on the formation, shifting and breaking of chemical bonds. It was determined that the yarn number, braiding geometry, braiding angle (°) and braid construction had no effect on the formation or shifting of chemical bonds. New bonds were formed thanks to CHI and GA due to their extremely reactive between 5 and 5.5 pH. They reacted quickly with Schiff base bond in all samples. CHI was ionized in all samples. It was determined that new bonds were formed in UHMWPE, PPD-T and HT PET structures. The most common bond formations were HT PET > PPD-T > UHMWPE. The reasons for these chemical structure changes in all samples depended on their chemical structures, bond types, molecular weights, reactivities, ease and speed of diffusions, crystallinities of technical yarns and all chemicals used. In order to increase the formation of new chemical bonds the pH should be between 5 and 5.5. GA concentration should be a minimum of 25% or higher. The dissolution time of CHI should be minimum 3 h or more. The dissolution process temperature of CHI should be minimum of 70°C or higher. The absorption, adsorption and chelation properties of CHI on all samples will also be evident successfully as in this experimental chemical study.