Composites Based on Hydroxyapatite and Whey Protein Isolate for Applications in Bone Regeneration

Abstract

Hydroxyapatite (HAp) is a bioactive ceramic with great potential for the regeneration of the skeletal system. However, its mechanical properties, especially its brittleness, limit its application. Therefore, in order to increase its ability to transmit stresses, it can be combined with a polymer phase, which increases its strength without eliminating the important aspect of bioactivity. The presented work focuses on obtaining organic–inorganic hydrogel materials based on whey protein isolate (WPI) reinforced with nano-HAp powder. The proportion of the ceramic phase was in the range of 0–15%. Firstly, a physicochemical analysis of the materials was performed using XRD, FT-IR and SEM. The hydrogel composites were subjected to swelling capacity measurements, potentiometric and conductivity analysis, and in vitro tests in four liquids: distilled water, Ringer’s fluid, artificial saliva, and simulated body fluid (SBF). The incubation results demonstrated the successful formation of new layers of apatite as a result of the interaction with the fluids. Additionally, the influence of the materials on the metabolic activity according to ISO 10993-5:2009 was evaluated by identifying direct contact cytotoxicity towards L-929 mouse fibroblasts, which served as a reference. Moreover, the stimulation of monocytes by hydrogels via the induction of nuclear factor (NF)-κB was investigated. The WPI/HAp composite hydrogels presented in this study therefore show great potential for use as novel bone substitutes.

Various Simulated Body Fluids Lead to Significant Differences in Collagen Tissue Engineering Scaffolds

“…Although some studies have focused on the comparison of the impact of various simulated body fluids on protein-based scaffolds [ 42 ], to the best of our knowledge, no such study that focuses on collagen scaffolds has been conducted to date. Thus, such information must be determined from individual studies that typically concern scaffolds with various compositions under differing conditions (e.g., media, time exposure, temperature, enzymatic degradation).…”

Recent Advances in the Treatment of Bone Metastases and Primary Bone Tumors: An Up-to-Date Review

“…Such structures can be derived by cells or directly obtained from decellularized bone tissue. Nonetheless, synthetic polymers provide better control of porosity and physicochemical properties, being promising biomaterials for bone tissue engineering [9,16,178,179]. Intensive research has also been directed to scaffolds made of bioceramics and their composites, as they have the necessary properties for biological activity in regard to cell adhesion, migration, and proliferation.…”

“…Historically, their inherently low fracture toughness and strength limited their use in load-bearing applications, but the currently known variety of bioceramics composition has allowed the adjustment of these materials' mechanical features, bioactivity, and degradation rate [160,161,180,181]. Another possibility of producing scaffolds with tailored properties is developing composites containing different bioceramics and polymers in different ratios [161,178,179].…”

Preparation, Characterization, and Biocompatibility Assessment of Polymer-Ceramic Composites Loaded with Salvia officinalis Extract

“…Once the entire system was brought to a boil, (CH 3 COO) 2 Ca (0.128 mol/L) was dropped in at a rate of 1 drop/sec. After completion of the synthesis, the HA suspension was cooled down and set aside for 24 h. After this time, the precipitate was washed thoroughly with distilled water, brought to neutral pH and dried [22].…”

“…However, due to the ease of combining ceramics with other materials, especially polymers, these disadvantages can be overcome by suspending the ceramics in a polymer matrix, leading to a composite material. This results in a biomaterial with improved mechanical properties without losing the bioactive nature of HA [21,22].…”