Synthesis of Hydroxyapatite Crystals From Egg Shells

The aim of the review is to raise awareness to synthesise hydroxyapatite (HAp) crystals from eggshells. The development of hydroxyapatite crystals shows a systematic approach towards the development in various biomedical applications.  The economic approach of the synthesis of crystalline hydroxyapatite crystals from the eggshells is done using ultrasound assisted technology. The study demonstrates the use of biowastes such as egg shells which is a promising technique to develop hydroxyapatite crystals due to its mechanical and osteogenic properties. The hydroxyapatite crystals are synthesised using biowastes such as egg shells which are rich in calcium and ammonium dihydrogen phosphate. This is a viable substitute for bone regeneration and orthodontic appliances due to its properties such as fracture toughness, mechanical strength, elastic modulus, osteoconductivity, bioactivity and differentiation. These minerals are similar to the inorganic content of the bone and are used widely for complete or partial bone augmentation, filling bone and teeth. They are used as coatings in orthopaedics and dental implants. The organic components of the matrix of the egg shells are mainly composed of mucopolysaccharides, proteins, mainly composed of chondroitin sulphate A and B, glucosamine, galactosamine, galactose, mannose, fructose and sialic acid. They are widely used as the matrix fibres have a strong influence on the mechanical strength of the entire egg shells. These crystals are characterised for bone tissue engineering due to the following properties such as biocompatibility, bioactivity and other mechanical properties without getting rejected by the immune system.