Synthesis and Characterization of Hydroxyapatite from Caprine (Goat) Bone for Microbial Adsorption and Antimicrobial Study

Abstract

In this work, natural hydroxyapatite (HAp) was extracted from bio-waste namely caprine (goat) bone by two different methods such as thermal treatment only and chemical method followed by thermal treatment. Thus produced HAp was characterized by different scientific tools like XRD, FTIR and SEM analyses. The specific surface area of HAp was found to be 144.89 m viii

2 /g measured by using methylene blue adsorption method. Similarly, pHPZC value was calculated as 7.2 determined by using pH drift method. Adsorption study of different microorganisms on the extracted HAp as a functions of various parameters like concentration of adsorbate, contact time and adsorbent dose was studied. The maximum adsorption efficiency at pH 7 for Escherichia coli, Candida albicans, Staphylococcus aureus and Acinetobacter baumanii was found to be 32.57 × 10 5 , 37.17 × 10 5 , 6.7 × 10 5 and 43.47 × 10 cfu/mg respectively from Langmuir adsorption isotherm model. The contact time required for maximum adsorption fell within 25 mins. for all microorganisms. The experimental data was best fitted with pseudo-second order kinetics model. HAp showed the antimicrobial activity only upon Acinetobacter baumanii among the studied microorganisms. MIC and MBC values of HAp were found to be 6.25 and 100 mg/mL respectively against Acinetobacter baumanii. Thus, hydroxyapatite was synthesized from bio-waste caprine (goat) bone which can be used as an adsorbent in microbial adsorption and an antimicrobial agent. Keywords: Natural hydroxyapatite, Bio-waste, Adsorption, Microorganisms, Antimicrobial activity