The Synthesis and Characterization of Hydroxyapatite-β-Alanine Modified by Grafting Polymerization of γ-Benzyl-l-glutamate-N-carboxyanhydride

Molecules

Yukai Shan¹  Yuyue Qin²  Yongming Chuan¹  Hongli Li¹ 

[1] Engineering Research Center of Biopolymer Functional Materials of Yunnan, Yunnan University of Nationalities, Kunming 650500, China;Institute of Chemical Engineering, Kunming University of Science and Technology, Kunming 650500, China

关键词: hydroxyapatite;    β-alanine;    γ-benzyl-l-glutamate-N-carboxyanhydride;    surface modification;    hydroxyapatite-β-alanine-poly(γ-benzyl-l-glutamates);   

DOI  :  10.3390/molecules181113979

来源: mdpi

【 摘 要 】

In this study, hydroxyapatite (HAP) was surface-modified by the addition of β-alanine (β-Ala), and the ring-opening polymerization of γ-benzyl-l-glutamate-N-carboxy-anhydride (BLG-NCA) was subsequently initiated. HAP containing surface poly-γ-benzyl-l-glutamates (PBLG) was successfully prepared in this way. With the increase of PBLG content in HAP-PBLG, the solubility of HAP-PBLG increased gradually and it was ultimately soluble in chloroform. HAP-PLGA with surface carboxyl groups was obtained by the catalytic hydrogenation of HAP-PBLG. In the process of HAP modification, the morphology changes from rod to sheet and from flake to needle. The effect of BLG-NCA concentration on the character of hydroxyapatite-β-alanine-poly(γ-benzyl-l-glutamate) (HAP-PBLG) was investigated. The existence of amino acids on the HAP surfaces was confirmed in the resulting Fourier transform infrared (FTIR) spectra. The resulting powder X-ray diffraction patterns indicated that the crystallinity of HAP decreased when the ratio of BLG-NCA/HAP-NH₂ increased to 20/1. Transmission electron microscopy (TEM) indicated that the particle size of HAP-PBLG decreased significantly and that the resulting particles appeared less agglomerated relative to that of the HAP-NH₂ crystals. Furthermore, ¹H-NMR spectra and FTIR spectra revealed that hydroxyapatite-β-alanine-poly (l-glutamic acid) (HAP-PLGA) was able to successfully bear carboxylic acid groups on its side chains.

【 授权许可】

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