Calcium Phosphate Loaded Biopolymer Composites—A Comprehensive Review on the Most Recent Progress and Promising Trends

Abstract

Biocompatible ceramics are extremely important in bioengineering, and very useful in many biomedical or orthopedic applications because of their positive interactions with human tissues. There have been enormous efforts to develop bioceramic particles that cost-effectively meet high standards of quality. Among the numerous bioceramics, calcium phosphates are the most suitable since the main inorganic compound in human bones is hydroxyapatite, a specific phase of the calcium phosphates (CaPs). The CaPs can be applied as bone substitutes, types of cement, drug carriers, implants, or coatings. In addition, bioresorbable bioceramics have great potential in tissue engineering in their use as a scaffold that can advance the healing process of bones during the normal tissue repair process. On the other hand, the main disadvantages of bioceramics are their brittleness and poor mechanical properties. The newest advancement in CaPs doping with active biomolecules such as Mg, Zn, Sr, and others. Another set of similarly important materials in bioengineering are biopolymers. These include natural polymers such as collagen, cellulose acetate, gelatin, chitosan, and synthetic polymers, for example, polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), and polycaprolactone (PCL). Various types of polymer have unique properties that make them useful in different fields. The combination of CaP particles with different biopolymers gives rise to new opportunities for application, since their properties can be changed and adjusted to the given requirements. This review offers an insight into the most up-to-date advancements in the preparation and evaluation of different calcium phosphate–biopolymer composites, highlighting their application possibilities, which largely depend on the chemical and physical characteristics of CaPs and the applied polymer materials. Overall, these composites can be considered advanced materials in many important biomedical fields, with potential to improve the quality of healthcare and to assist in providing better outcomes as scaffolds in bone healing or in the integration of implants in orthopedic surgeries.