Waste to health- seashells and pumpkin seeds into nanohydroxyapatite

Abstract

Tonnes of pumpkin and piles of sea shells were amassed as waste products every year in the environment. Poor handling of waste can cause environmental pollution and globally initiatives have been made to take of them. Moreover, the focus on turning the waste into useful products hinders the dumping of waste and aids their management. Nanohydroxyapatite, a bioactive bone mineral, has emerged as an ideal candidate for bone substitution applications. The current study focuses on two main goals: waste management and the biogenic preparation of a value-added product, natural nanohydroxyapatite (Nat-Apatite). The seashells and Cucurbita maxima (Pumpkin seeds), which are often discarded as garbage, were utilized as a calcium source and phosphorous source, respectively. The Nat-Apatite exhibited a unique nanoglobular morphology and contained trace elements, such as strontium, magnesium, and sulphur. To assess the degradation rate of Nat-Apatite, we employed electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The results demonstrated a slow degradation rate, indicating potential compatibility with natural bone remodeling processes. Ex-vivo bone mineralization studies revealed that Nat-Apatite could promote nanoplatelet-like structures on decalcified bone surfaces. Furthermore, our study found that Nat-Apatite effectively enhanced the cell viability. Additionally, MG63 cells treated with Nat-Apatite showed increased production of calcium nodules, collagen, and alkaline phosphatase levels, suggesting improved osteogenic differentiation and bone formation. Thereby, the prepared Nat-Apatite can be potentially employed for biomedical applications.