Effects of modification of calcium hydroxyapatites by trivalent metal ions on the protein adsorption behavior.

The effects of modification of calcium hydroxyapatites (Hap; Ca10(PO4)6(OH)2) by trivalent metal ions (Al(III), La(III), and Fe(III)) on protein adsorption behavior were examined using bovine serum albumin (BSA; isoelectric point (iep) = 4.7 and molecular mass (M(s)) = 67,200 Da). The Al(III)-, La(III)-, and Fe(III)-substituted Hap particles were prepared by the coprecipitation method with different atomic ratios, metal/(Ca + metal), abbreviated as X(metal).

Effects of heat treatment of calcium hydroxyapatite particles on the protein adsorption behavior.

The effects of heat treatment of calcium hydroxyapatite (Hap) on the protein adsorption behavior were examined using typical proteins of bovine serum albumin (BSA: isoelectric point (iep) = 4.7, molecular mass (Ms) = 67,200 Da, acidic protein), myoglobin (MGB: iep = 7.0, Ms = 17,800 Da, neutral protein), and lysozyme (LSZ: iep = 11.

Synthesis of positively charged calcium hydroxyapatite nano-crystals and their adsorption behavior of proteins.

Positively charged Hap nano-crystals were prepared by using beta-alanine and clarified the adsorption affinity of these surface amide functionalized Hap nano-crystals to proteins. Colloidal surface amide functionalized Hap nano-crystals were prepared by wet method in the presence of various amounts of beta-alanine by changing molar ratio of beta-alanine/Ca (beta/Ca ratio) in the solution. The rod-like nano-crystals were lengthened with addition of beta-alanine though their width did not vary; carboxyl groups of beta-alanine are strongly coordinated to Ca2+ ions exposed on ac and/or bc faces to inhibit particle growth to a- and/or b-axis directions and enhance the particle growth along to the c-axis.

Thermolysis of gold(I) thiolate complexes producing novel gold nanoparticles passivated by alkyl groups.

Thermolysis of gold(I) thiolate complex, [C14H29(CH3)3N][Au(SC12H25)2], at 180 degrees C for 5 h under an N2 atmosphere produces novel gold nanoparticles passivated by alkyl groups derived from the precursor complex, the TEM image of which shows spherical particles with average diameter 26 nm.