Agarose encapsulated mesoporous carbonated hydroxyapatite nanocomposites powder for drug delivery

- Nanosized carbonated hydroxyapatite (CHAp/agarose) powder by solvothermal route
- Encapsulation on CHAp powder and bio-medical properties were assessed.
- Nanocomposite powders are used for filling of voids in bone materials.
- Drug delivery carrier to prevent the infection of the damaged tissues
- Nanocomposites exhibit antimicrobial activity of E. coli, S. aureus & S. epidermidis.

The powder composites are predominantly used for filling of voids in bone and as drug delivery carrier to prevent the infection or inflammatory reaction in the damaged tissues. The objective of this work was to study the synthesis of agarose encapsulation on carbonated hydroxyapatite powder and their biological and drug delivery properties. Mesoporous, nanosized carbonated hydroxyapatite/agarose (CHAp/agarose) powder composites were prepared by solvothermal method and subsequently calcined to study the physico-chemical changes, if it subjected to thermal exposure. The phase of the as-synthesized powder was CHAp/agarose whereas the calcinated samples were non-stoichiometric HAp. The CHAp/agarose nanorods were of length 10-80 nm and width 40-190 nm for the samples synthesized at temperatures 120 °C (ST120) and 150 °C (ST150). The calcination process produced spheres (10-50 nm) and rods with reduced size (40-120 nm length and 20-30 nm width). Composites were partially dissolved in SBF solution followed by exhibited better bioactivity than non-stoichiometric HAp confirmed by gravimetric method. Hemo and biocompatibility remained unaffected by presence of agarose or carbonate in the HAp. Specific surface area of the composites was high and exhibited an enhanced amoxicillin and 5-fluorouracil release than the calcined samples. The composites demonstrated a strong antimicrobial activity against E. coli, S. aureus and S. epidermidis. The ST120 showed prolonged drug (AMX and 5-Fcil) release and antimicrobial efficacy than ST150 and calcined samples. This technique would be simple and rapid for composites preparation, to produce high quality crystalline, resorbable, mesoporous and bioactive nanocomposite (CHAp/agarose) powders. This work provides new insight into the role of agarose coated on bioceramics by solvothermal technique and suggests that CHAp/agarose composites powders are promising materials for filling of void in bone and drug delivery applications.

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