Utilization Of Kijing (Pilsbryoconcha exilis) Shell Waste As A Source Of Hydroxyapatite By Double Stirring And Precipitation Methods As Biomaterials

Abstract Research has been conducted on the synthesis and characterization of hydroxyapatite of kijing shells. Kijing shells (Pilsbryoconcha exilis) are a potential natural resource in the Belawan mangrove forest area, North Sumatra. Kijing shells have a high calcium content which has the potential to be utilized as a calcium precursor in the synthesis of hydroxyapatite (HAp) using the double stirring and precipitation method at variations in sintering temperatures of 800°C, 900°C, and 1.000°C. The synthesis of HA by the precipitation method involves mixing calcium (Ca) and phosphorus (P) solutions through a titration process. The double stirring method combining magnetic and ultrasonic stirring improves the homogeneity of the reaction. Analysis of kijing shell ash using XRF shows that the dominant element content is the element Calcium (Ca) of 64,268% with Calcium Oxide (CaO) compounds of 52,482%. The results of characterization using XRD show that HAp obtained has a degree of crystallinity of 22,13%, 29,95%, and 32,95%, respectively. The highest degree of crystallinity value at 1000°C. The average crystal size of the three samples is 32-68 nm which meets the standards of biomedical applications. The crystal structure of the hydroxyapatite of the three samples is hexagonal. From the results of the FTIR test, the three samples obtained wave numbers indicating the functional groups 0H − , PO 4 3- , CO 3 2- , which are the dominant functional groups that make up hydroxyapatite. The results of SEM analysis on the hydroxyapatite of the three samples have porosity. EDX results show the Ca/P ratio of the three samples are 1,67; 1,45; and 1,61, respectively. Sample A1 has an average pore diameter of 1.960,77 nm, A2 of 1.234 nm, A3 of 925,899 nm.