Apatite containing aspartic acid for selective protein loading.
Physico-chemical modifications of hydroxyapatite (HAp) materials are considered as pre-requisites for the development of new bioactive carrier materials for drug delivery and tissue engineering applications. Since acidic amino acids have well-documented affinities to both HAp and basic proteins, HAp modified by aspartic acid (Asp, acidic amino acid) might be one of the candidate substrates for a basic protein carrier. Here, we synthesized HAp in the presence of various concentrations of Asp and observed that HAp crystallinity and other physico-chemical properties were effectively modulated. Detailed studies indicated that Asp was not incorporated in the HAp crystal lattice, but rather was trapped in HAp crystals. Protein adsorption studies indicated that the HAp particles modified by Asp had a selective loading capacity for basic protein. Therefore, HAp particles containing Asp might have potential in drug delivery applications, especially as the carrier of basic proteins including bFGF and BMP.
Department of Oromaxillofacial Regeneration, Osaka University, 1-8 Yamada-oka, Suita, 565-0871, Japan.
M Hafiz
MH
Uddin
T
T
Matsumoto
S
S
Ishihara
A
A
Nakahira
M
M
Okazaki
T
T
Sohmura
D000327:Adsorption; D001224:Aspartic Acid / Q000737:chemistry*; D019485:Bone Morphogenetic Proteins / Q000737:chemistry; D002118:Calcium / Q000032:analysis; D055598:Chemical Phenomena; D003461:Crystallography; D004337:Drug Carriers; D016503:Drug Delivery Systems; D017886:Durapatite / Q000737:chemistry*; D016222:Fibroblast Growth Factor 2 / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D046529:Microscopy, Electron, Transmission; D010758:Phosphorus / Q000032:analysis; D011485:Protein Binding; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013818:Thermogravimetry; D023822:Tissue Engineering; D014961:X-Ray Diffraction
D019485:Bone Morphogenetic Proteins; D004337:Drug Carriers; D016222:Fibroblast Growth Factor 2; D010758:Phosphorus; D001224:Aspartic Acid; D017886:Durapatite; D002118:Calcium