Analysis of the Influence of Hydroxyapatite on the Morphology and Absorption Capacity of PHB Membranes

Biomaterials are substances, either natural or synthetic, capable of interacting with the biological system. The effectiveness of these biomaterials relies on their physicochemical, morphological, and mechanical properties, as well as their ability to adhere to tissue cells, promoting healing. These biomaterials can be incorporated into bioceramics such as HAp, promoting bone neoformation. The objective was to obtain and characterize PHB and hydroxyapatite membranes with the prospect of their use as biomaterials for bone repair. This study outlines the process of preparing PHB/HAp composite membranes, including the chemical precipitation method used to obtain HAp powder and the membrane processing through solvent evaporation. The membrane morphology is analyzed using both optical and scanning electron microscopy (SEM), while the crystalline structure is evaluated through X-ray diffractometry. Water absorption tests are conducted following specific standards. Statistical analysis is carried out to interpret the results. In this study, PHB and PHB/HAp membranes were prepared using chloroform via solvent evaporation. The addition of HAp resulted in a rough and heterogeneous membrane surface. Membrane morphology was evaluated using optical microscopy, and PHB/HAp showed regular clusters, indicating the presence of HAp. X-ray diffraction analysis confirmed the crystallinity of HAp. The crystallinity of PHB membranes did not significantly change with the addition of HAp. The membranes exhibited absorption capacity in different mediums, being more absorbent in water, followed by artificial saliva and physiological solution. The PHB/HAp membrane lost more mass in physiological solution over time, while gaining more mass in water within 2 hours.