TY - JOUR

T1 - Low-Temperature Synthesis and Surface Modification of High Surface Area Calcium Hydroxyapatite Nanorods Incorporating Organofunctionalized Surfaces

AU - Anwar, A.

AU - Rehman, I.U.

AU - Darr, J.A.

PY - 2016/12/29

Y1 - 2016/12/29

N2 - A new low-temperature continuous approach for the surface modification of hydroxyapatite (HA) is described. In this method, the HA particle surfaces were modified using methacrylic acid, vinylphosphonic acid, adipic acid, citric acid, or polyvinyalcohol, respectively, using a continuous plastic flow synthesis (CPFS) system at a reaction temperature of 70 °C for 5 min. The materials were investigated using a range of analytical techniques, including TEM (transmission electron microscopy), zeta potential, XRD (X-ray diffraction), BET (Brunauer-Emmett-Teller) surface area analysis, FTIR (Fourier transform infrared) spectroscopy, and XPS (X-ray photoelectron spectroscopy). The presence of organic agents in the reagents, resulted in a significant reduction in particle size of the nano-HA rods; TEM studies confirmed the formation of highly dispersed nanorods of HA with average lengths and diameters in the ranges 20-60 nm and 4-10 nm, respectively. XPS analyses suggested that the Ca:P molar ratio decreased from 1.67 to ca. 1.34 by the addition of organic surface agents. The zeta potential measurements revealed that the colloidal stability of surface-modified HA generally increased (under certain conditions) compared to ungrafted HA. The small size and presence of functional groups make these materials potentially suitable for dental restoration fillers and composite bone regeneration applications. © 2016 American Chemical Society.

AB - A new low-temperature continuous approach for the surface modification of hydroxyapatite (HA) is described. In this method, the HA particle surfaces were modified using methacrylic acid, vinylphosphonic acid, adipic acid, citric acid, or polyvinyalcohol, respectively, using a continuous plastic flow synthesis (CPFS) system at a reaction temperature of 70 °C for 5 min. The materials were investigated using a range of analytical techniques, including TEM (transmission electron microscopy), zeta potential, XRD (X-ray diffraction), BET (Brunauer-Emmett-Teller) surface area analysis, FTIR (Fourier transform infrared) spectroscopy, and XPS (X-ray photoelectron spectroscopy). The presence of organic agents in the reagents, resulted in a significant reduction in particle size of the nano-HA rods; TEM studies confirmed the formation of highly dispersed nanorods of HA with average lengths and diameters in the ranges 20-60 nm and 4-10 nm, respectively. XPS analyses suggested that the Ca:P molar ratio decreased from 1.67 to ca. 1.34 by the addition of organic surface agents. The zeta potential measurements revealed that the colloidal stability of surface-modified HA generally increased (under certain conditions) compared to ungrafted HA. The small size and presence of functional groups make these materials potentially suitable for dental restoration fillers and composite bone regeneration applications. © 2016 American Chemical Society.

KW - Calcium

KW - Filling

KW - Fourier transform infrared spectroscopy

KW - High resolution transmission electron microscopy

KW - Hydroxyapatite

KW - Low temperature effects

KW - Nanorods

KW - Particle size

KW - Surface treatment

KW - Temperature

KW - Transmission electron microscopy

KW - X ray diffraction

KW - Zeta potential

KW - Brunauer emmett tellers

KW - Calcium hydroxyapatite

KW - Fourier transform infra reds

KW - Low temperature synthesis

KW - Surface area analysis

KW - TEM (transmission electron microscopy)

KW - Xrd (x ray diffraction)

KW - Zeta potential measurements

KW - X ray photoelectron spectroscopy

U2 - 10.1021/acs.jpcc.6b05878

DO - 10.1021/acs.jpcc.6b05878

M3 - Journal article

VL - 120

SP - 29069

EP - 29076

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 51

ER -