The Effect of Alginate Concentration on Crystallinity, Morphology, and Thermal Stability Properties of Hydroxyapatite/Alginate Composite

Abstract

Hydroxyapatite (HAp) has been used for various applications such as orthopedics, drug delivery material, and bone tissue engineering. It is well known that HAp has a good biocompatibility and osteoconductivity, so HAp can be used in biomedical applications. Hydroxyapatite can be combined with other materials, in particular polymer, to expand its range of applications. In this study, the polymer that will be used as a support for the HAp composite is alginate (Alg). The HAp/Alg composite has been synthesized by the precipitation method. The XRD results show that the crystal system of HAp was hexagonal. The spheric-like shaped particles can be observed from SEM images, and particle size distribution spread from 400 to 1100 nm. The EDS spectrum exhibited the peak of Ca, C, P, and O elements, indicating that alginate had interacted with hydroxyapatite in the synthesized composite. The as-fabricated composite showed not only good crystallinity but also high thermal resistance. Thermogravimetric-differential thermal analysis (TGA-DTA) revealed that the HAp/Alg composites have a constant weight at 750 °C, so it might be applied in advanced applications such as bioimaging, drug carrier, and other cancer treatments.

Synthesis and Characterization of Hydroxyapatite Composite from Cuttlebone (Sepia sp.) with Chitosan via In Situ as Antibacterial

“…[12,25] The natural sources of calcium used in HAp synthesis can come from mammals, minerals, shells, egg shells, and aquatic. [11,20,26] Chitosan comes from waste shrimp shells containing 20-30 % chitin compounds and is usually only used as animal feed. The HAp/CTS composite was tested for its antibacterial activity against S. Aureus and E. coli bacteria.…”

“…One such material is a polymer. HAp/polymer composite combinations, such as HAp/alginate, HAp/gelatin, and HAp/chitosan, are widely used in the medical field [2,11,12] . Chitosan (CTS) is a natural polymer derivative of chitin, which is the second most abundant polysaccharide after cellulose.…”

“…HAp from cuttlebone has been developed in the medical field, combining it with gelatin‐based hydrogel and L‐rhamnose monohydrate biosurfactant, which produces an environmentally friendly [12,25] . The natural sources of calcium used in HAp synthesis can come from mammals, minerals, shells, egg shells, and aquatic [11,20,26] . Chitosan comes from waste shrimp shells containing 20–30 % chitin compounds and is usually only used as animal feed.…”

“…HAp/polymer composite combinations, such as HAp/alginate, HAp/gelatin, and HAp/chitosan, are widely used in the medical field. [2,11,12] Chitosan (CTS) is a natural polymer derivative of chitin, which is the second most abundant polysaccharide after cellulose. CTS is a copolymer of D-glucosamine and N-acetyl-D-glucosamine, and has non-toxic, antibacterial, biocompatible, and biodegradable properties.…”

“…[19] Composites can be synthesized by several methods, such as hydrothermal, precipitation, mechanochemical, and sol-gel. [11,[20][21][22][23] However, the solgel method has more advantages because it produces material with high purity and homogeneity and relatively low temperature. [20] pH is one of the parameters that influences a material's final morphology, crystallinity, and yield.…”