TY - JOUR
T1 - Functionalization of different polymers with sulfonic groups as a way to coat them with a biomimetic apatite layer
AU - Leonor, I. B.
AU - Kim, H. M.
AU - Balas, F.
AU - Kawashita, M.
AU - Reis, R. L.
AU - Kokubo, T.
AU - Nakamura, T.
N1 - Funding Information:
Acknowledgments I. B. Leonor thanks the Portuguese Foundation for Science and Technology for providing her a PhD scholarship (SFRH/BD/9031/2002). This work was partially supported by FCT Foundation for Science and Technology, through funds from the POCTI and/or FEDER programmes.
PY - 2007/10
Y1 - 2007/10
N2 - Covalent coupling of sulfonic group (-SO3H) was attempted on different polymers to evaluate efficacy of this functional group in inducing nucleation of apatite in body environment, and thereupon to design a simple biomimetic process for preparing bonelike apatite-polymer composites. Substrates of polyethylene terephthalate (PET), polycaprolactam (Nylon 6), high molecular weight polyethylene (HMWPE) and ethylene-vinyl alcohol co-polymer (EVOH) were subjected to sulfonation by being soaked in sulfuric acid (H2SO 4) or chlorosulfonic acid (ClSO3H) with different concentrations. In order to incorporate calcium ions, the sulfonated substrates were soaked in saturated solution of calcium hydroxide (Ca(OH)2). The treated substrates were soaked in a simulated body fluid (SBF). Fourier transformed infrared spectroscopy, thin-film X-ray diffraction, and scanning electron microscopy showed that the sulfonation and subsequent Ca(OH) 2 treatments allowed formation of -SO3H groups binding Ca2+ ions on the surface of HMWPE and EVOH, but not on PET and Nylon 6. The HMWPE and EVOH could thus form bonelike apatite layer on their surfaces in SBF within 7 d. These results indicate that the -SO3H groups are effective for inducing apatite nucleation, and thereby that surface sulfonation of polymers are effective pre-treatment method for preparing biomimetic apatite on their surfaces.
AB - Covalent coupling of sulfonic group (-SO3H) was attempted on different polymers to evaluate efficacy of this functional group in inducing nucleation of apatite in body environment, and thereupon to design a simple biomimetic process for preparing bonelike apatite-polymer composites. Substrates of polyethylene terephthalate (PET), polycaprolactam (Nylon 6), high molecular weight polyethylene (HMWPE) and ethylene-vinyl alcohol co-polymer (EVOH) were subjected to sulfonation by being soaked in sulfuric acid (H2SO 4) or chlorosulfonic acid (ClSO3H) with different concentrations. In order to incorporate calcium ions, the sulfonated substrates were soaked in saturated solution of calcium hydroxide (Ca(OH)2). The treated substrates were soaked in a simulated body fluid (SBF). Fourier transformed infrared spectroscopy, thin-film X-ray diffraction, and scanning electron microscopy showed that the sulfonation and subsequent Ca(OH) 2 treatments allowed formation of -SO3H groups binding Ca2+ ions on the surface of HMWPE and EVOH, but not on PET and Nylon 6. The HMWPE and EVOH could thus form bonelike apatite layer on their surfaces in SBF within 7 d. These results indicate that the -SO3H groups are effective for inducing apatite nucleation, and thereby that surface sulfonation of polymers are effective pre-treatment method for preparing biomimetic apatite on their surfaces.
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U2 - 10.1007/s10856-007-3106-6
DO - 10.1007/s10856-007-3106-6
M3 - Article
C2 - 17554598
AN - SCOPUS:34548741299
VL - 18
SP - 1923
EP - 1930
JO - Journal of Materials Science: Materials in Medicine
JF - Journal of Materials Science: Materials in Medicine
SN - 0957-4530
IS - 10
ER -