Controlled Crystallization of Nanocrystalline Apatite via Vapor Diffusion on Bacterial Cellulose Membranes Obtained from Mango Waste

Hybrid bacterial cellulose (BC)-calcium phosphate apatite (Ap) composite was successfully synthesized via the sitting drop vapor diffusion crystallization method. The BC matrix was produced using the bacterial strain <i>Komagataeibacter</i> sp. SU12 cultured in a medium derived from mango juice waste, underscoring a sustainable strategy for biopolymer production. The resulting BC-Ap composite exhibited plate-like apatite crystals, as confirmed by X-ray diffraction analyses, which were heterogeneously distributed on the BC matrix and coupled to the nanocellulose surface fibers. An increase in mineral content in the BC-Ap composites over the experimental reaction times (1-15 days) was observed by thermogravimetry analyses. Spectroscopic analyses confirmed the presence of characteristic BC functional groups (e.g., hydroxyl and carboxylate), and the vibrational modes associated with phosphate (ν₁-ν₄ of PO₄ ^3-), corroborating the formation of apatite within the BC-Ap material. These findings suggest that the vapor diffusion crystallization method is an effective approach for the controlled mineralization of BC nanofibers with nanocrystalline apatite, yielding a bioinspired material with promising potential application in bone tissue engineering. Additionally, the use of mango-processing waste as a carbon source for BC production offers a sustainable and cost-efficient alternative, supporting the advancement of green technology and biocompatible routes for material design.