Degradation and release of isoniazid and rifampicin nano hydroxyapatite-calcium sulfate artificial bone in vitro

English Keywords:Isoniazid  Rifampicin  Nano hydroxyapatite  Calcium sulfate  Sustained-release

English Abstract:

  【Abstract】 Objectives: To observe the degradation and drug release properties of isoniazid(INH) and rifampicin(RFP) nano hydroxyapatite(nHA)-calcium sulfate (CSH) artificial bone in vitro. Methods: The prepared artificial bone was degraded in simulated body fluid at 37 degrees centigrade and taken out at 24h, 72h, 1w, 2w, 4w, 6w, 8w, 10w, 12W, respectively. The degradation degree of artificial bone surface was observed by scanning electron microscope, and the quality changes were measured. The compressive strength of artificial bone at each time point was tested by electronic universal test machine. The artificial bone was placed at PBS at 37 degrees centigrade for release, the release concentration of INH and RFP at nine phase points of 24h, 72h, 1w, 2w, 4w, 6w, 8w, 10w and 12w were detected by high performance liquid chromatography (HPLC). The cumulative drug release percentage was calculated, and the drug release rate was observed. Results: With the prolongation of soaking time, the volume of artificial bone gradually decreased and the color became white. And the crystal structure of the artificial bone surface disappeared gradually and the pores decreased, and the surface of artificial bone was covered by unstructured degradations by scanning electron microscope. The quality and compressive strength of artificial bone decreased with the degradation of artificial bone. The compressive strength at eighth weeks was still close to the strength of cancellous bone. During the process of artificial bone release, the cumulative release percentages of INH at 24h, 72h, 1w, 2w, 4w, 6w, 8w were 44.58%, 71.06%, 90.23%, 95.98%, 98.27%, 99.72%, 100%, respectively, which at 10w and 12w were not detected. The cumulative drug release percentages of RFP at 24h, 72h, 1w, 2w, 4w, 6w, 8w, 10w and 12w nine phases were 2.70%, 16.82%, 39.96%, 61.71%, 83.88%, 96.38%, 97.63%, 98.00%, 98.26%, respectively. Conclusions: Isoniazid and rifampicin nano hydroxyapatite-calcium sulfate artificial bone degrades steadily in vitro, and it has long and effective release performance.