Preparation of Inverse Opal Hydroxyapatite and Drug Delivery Properties.

Hydroxyapatite(HA) are widely used in the field of drug delivery, especially nano‐HA and porous HA. However, there are few reports on the use of inverse opal HA as drug carrier. In this paper, based on the colloidal crystal template prepared by polystyrene microsphere with the diameter of 380 ± 10 nm, inverse opal HA was prepared by template method as the drug sustained‐release carrier using different dispersants and ratio of template to precursor. The results indicated that when the ratio of template to precursor was 1 : 15 and the dispersant was a mixture of water and alcohol, the prepared inverse opal HA showed a complete ordered porous morphology with uniform pore spacing. In the drug delivery test of amoxicillin, drug loading and release properties of the inverse opal HA were significantly better than that of nano‐HA. Drug loading of the inverse opal HA was about 2.17 times than that of nano‐HA, and drug‐loading performance was also obviously improved. At the same time, sustained release ability of the inverse opal HA was better than that of nano‐HA when releasing amoxicillin. In the first 3 h, the cumulative release rate of amoxicillin in the inverse opal HA was less than 40%, much lower than about 60% of nano‐HA, significantly slowing down the drug release rate and showing good persistence. Therefore, the inverse opal HA as a drug carrier could also improve the sudden release effect of drugs and make the release rate of drugs gentler. [ABSTRACT FROM AUTHOR]