Hydroxyapatite-gelatin-HPMC composite as injectable bone substitute with alendronate variation for osteoporotic bone

Abstract

The treatment of bone with osteoporosis could be done by filling the bone defect with Injectable Bone Substitute (IBS). IBS could be functioned as drug delivery system by associating a drug inside the IBS, such as alendronate for osteoporosis case. In this study, IBS has been synthesized and characterized with the alendronate variations. The IBS was synthesized by stirring hydroxyapatite and gelatin 5% (w/v) with a ratio of 45:55. The alendronate was added to the solution with composition of 0%, 5%, 10%, 15% and 20%. The mixture was mixed with 2% (w/v) HPMC. FTIR test results indicated the formation of hydroxyapatite-gelatin bonding (Ca2+-COO-) at wavenumber of 1560.54 cm-1. The acidity test result indicated that the sample had a pH of 7 and was able to remain stable. The IBS could be set in 3 hours and 38 minutes when injected to HA substrate and capable of enveloping the surface of HA substrate. The pore size of the substrate decreased from range of 153 to 625.8 μm into 247.4 to 480.8 μm. The XRD test results indicated that degree of crystallinity decreased from 76.81% to 75.13%. The best alendronate composition in IBS was 10% compared to the mass of hydroxyapatite.