Evaluation on cross-linked nano microbial cellulose properties as bone scaffold

Bacterial cellulose is produced by strains of Acetobacter and Acetobacter xylinum is the most important species producing it. Due to its nanostructure and morphological similarity to collagen, bacterial cellulose can be used for cell absorption and support. Consequently, this research presented a general description of bacterial cellulose, its applications in medicine, and utilization of hydroxyapatite/cross-linked bacterial cellulose composite scaffolds for bone tissue. Citric acid (20%) was used for cross-link, samples of bacterial cellulose were prepared and oven-dried, and hydroxyapatite (HAP) particles were then added at three concentrations (1, 2 and 4%). Using ATR-FTIR, XRD, FE-SEM, EDS and BET, the structure of the composites were compared. The results of ATR-FTIR confirmed that the HAP crystals contained a special carbonate that was similar to the apatite present in natural bone. XRD also indicated the characteristic peaks of HAP, and calculation of the size of the crystals using Scherrer equation demonstrated that the largest crystal size (81.42 nm) was that of the sample containing 20% citric acid with 4% HAP. Comparison of the FE-SEM images showed that the distribution and formation of apatite on the surface and cross-section were the best in the sample cross-linked with 20% citric acid and 4% apatite. The results of EDS analysis also indicated that all the precipitates contained calcium and phosphorus confirming the presence od HAP crystals, and the nanoparticles were also distributed uniformly in the scaffold structure. BET also showed that the sample cross-linked with 20% citric acid and 4% HAP had the lowest specific surface area and the highest porosity confirming the high uniformity of the 4% HAP distribution.