Preparation and Evaluation of Spray-Dried Nano-Hydroxyapatite/Saccharide Complex for Oral Administration

nanohydroxyapatite (nanoHA) is a main component of bone and dentin. The nanoHA was synthesized by a neutralization reaction of calcium hydroxide suspension and phosphoric acid solution. The sizes of the nanoHA were in the range of 5-80 nm. The composition and structure of the nanoHA was determined by XRD and FTIR as hydroxyapatite containing small amounts of carbonate. The morphology of the nanoHA was observed by TEM as plate shape. Saccharides including dextrin, lactose and glucose were mixed into the nanoHA suspension and dried by a spray dry method to produce a complex powder for oral administration. The particle sizes of the complex were in the range of 10-20 μm. The dispersibility of the complex in water was examined by a precipitation rate test and the order was as follows: glucose > dextrin > lactose complex.