title: Effect of calcium salt content in the poly(epsilon-caprolactone)/silica nanocomposite on the nucleation and growth behavior of apatite layer.
abstract: The effect of calcium salt content in the poly(epsilon-caprolactone) (PCL)/silica nanocomposite on the nucleation and growth behavior of apatite layer in simulated body fluid (SBF) was investigated. The specimens were prepared with low (L) and high (H) concentrations of calcium nitrate tetrahydrate through a sol-gel method. After soaking in the SBF at 36.5 degrees C for 1 week, a densely packed apatite layer that had a smooth surface and a Ca/P ratio similar to bone was formed on specimens containing a low concentration of calcium salt while a loosely packed apatite layer with a rugged surface and a higher Ca/P ratio than that of bone occurred on specimens containing a high concentration of calcium salt. The results are explained in terms of the degree of supersaturation of apatite in the SBF, as determined by the concentrations of constituent ions of apatite and pH. The practical implication of the results is that a dense and bone-like apatite layer on the PCL/silica nanocomposite in vitro, and perhaps in vivo, can be achieved by adopting an appropriate calcium salt content.
authors: Department of Dental Biomaterials Science, College of Dentistry, Seoul National University, Seoul 110-749, Korea. rhee1213@snu.ac.kr
authors: Sang-Hoon
authors: SH
authors: Rhee
mesh_terms: D001031:Apatites / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry; D001826:Body Fluids / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D009566:Nitrates / Q000737:chemistry*; D011091:Polyesters / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014961:X-Ray Diffraction
chemical_list: D001031:Apatites; D001672:Biocompatible Materials; D017610:Calcium Compounds; D009566:Nitrates; D011091:Polyesters; C016240:polycaprolactone; D012822:Silicon Dioxide; C059948:calcium nitrate