In order to establish a reasonable biomimetic condition for compressive strength of bioactive ceramics, the compressive strengths of several commercial bioactive ceramics were measured under various conditions. All specimens except for one of Japanese ceramics, specimen A, showed no significant differences among the conditions, but showed a tendency of decreasing the compressive strength more than 10% in comparison to the dry condition that was conventionally described in product brochures. Further, the specimen A indicated a significant decrease of the compressive strength in 24 h soaking conditions. Accordingly, a recommended biomimetic condition would be that specimen would be soaked in PBS after deaeration at 25 °C for 24 h and measured in air after brief wiping surface liquid.
{"title":"Effect of Test Circumstances on Compressive Strength of Porous Calcium Phosphate Ceramics for Establishment of Standard Measurement Condition","authors":"M. Kikuchi","doi":"10.4303/BDA/D101201","DOIUrl":"https://doi.org/10.4303/BDA/D101201","url":null,"abstract":"In order to establish a reasonable biomimetic condition for compressive strength of bioactive ceramics, the compressive strengths of several commercial bioactive ceramics were measured under various conditions. All specimens except for one of Japanese ceramics, specimen A, showed no significant differences among the conditions, but showed a tendency of decreasing the compressive strength more than 10% in comparison to the dry condition that was conventionally described in product brochures. Further, the specimen A indicated a significant decrease of the compressive strength in 24 h soaking conditions. Accordingly, a recommended biomimetic condition would be that specimen would be soaked in PBS after deaeration at 25 °C for 24 h and measured in air after brief wiping surface liquid.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134552107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dunstan H Barnes, R. Cameron, S. Kiamil, F. Meyer, R. Brooks, N. Rushton, S. Best
Discs of poly carbonate urethane (PCU) were coated with a thin layer of calcium phosphate (CaP) by a biomimetic process at temperatures of 28?C and 37?C. The coating morphology was analyzed by SEM. Contact angle analysis was used to assess surface wettability. Human osteoblasts (HOBs) were cultured on uncoated and CaP-coated PCU discs for up to 14 days. Cell metabolism, structure, and morphology were analyzed and compared with the wettability of each sample group. HOBs proliferated and grew on uncoated and CaP-coated samples, but a greater cell metabolism was observed for uncoated samples at early time points in cell culture. A more even dispersion of HOBs across the disc surface, attributable to the increased surface wettability, was seen for CaP-coated samples.
{"title":"Biomimetic Calcium Phosphate Coatings for Polymeric Artificial Spinal Disc Implants","authors":"Dunstan H Barnes, R. Cameron, S. Kiamil, F. Meyer, R. Brooks, N. Rushton, S. Best","doi":"10.4303/BDA/D101111","DOIUrl":"https://doi.org/10.4303/BDA/D101111","url":null,"abstract":"Discs of poly carbonate urethane (PCU) were coated with a thin layer of calcium phosphate (CaP) by a biomimetic process at temperatures of 28?C and 37?C. The coating morphology was analyzed by SEM. Contact angle analysis was used to assess surface wettability. Human osteoblasts (HOBs) were cultured on uncoated and CaP-coated PCU discs for up to 14 days. Cell metabolism, structure, and morphology were analyzed and compared with the wettability of each sample group. HOBs proliferated and grew on uncoated and CaP-coated samples, but a greater cell metabolism was observed for uncoated samples at early time points in cell culture. A more even dispersion of HOBs across the disc surface, attributable to the increased surface wettability, was seen for CaP-coated samples.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134239463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bioactivity and osteoconductivity of calcium phosphates as a function of ?-tricalcium phosphate contents, that is, biodegradability, were investigated. Three calcium phosphates, pure hydroxyapatite, biphasic calcium phosphates with different mixing ratios between hydroxyapatite, and ?-tricalcium phosphate (60HAp:40?- TCP and 40HAp:60?-TCP in wt.%), were synthesized through the precipitation method using calcium hydroxide and phosphoric acid as starting reactants. After drying, they were sintered at 1100 °C for 3 hours, and then bioactivity and osteoconductivity tests were carried out in simulated body fluid (SBF) and calvarial defect of New Zealand white rabbits, respectively. SBF exposure resulted in the deposition of a layer of carbonate apatite crystals on the surfaces of bicalcium phosphates but not on the hydroxyapatite. New bone forming capacity of the biphasic calcium phosphate with 60HAp:40?-TCP granules was the best, whereas that of the pure HAp was the worst. To this end, it can be concluded that the calcium phosphate with moderate biodegradability is good for producing good osteoconductivity.
{"title":"Bioactivity and Osteoconductivity of Biphasic Calcium Phosphates","authors":"Jung Sang Cho, C. Chung, S. Rhee","doi":"10.4303/BDA/D101129","DOIUrl":"https://doi.org/10.4303/BDA/D101129","url":null,"abstract":"Bioactivity and osteoconductivity of calcium phosphates as a function of ?-tricalcium phosphate contents, that is, biodegradability, were investigated. Three calcium phosphates, pure hydroxyapatite, biphasic calcium phosphates with different mixing ratios between hydroxyapatite, and ?-tricalcium phosphate (60HAp:40?- TCP and 40HAp:60?-TCP in wt.%), were synthesized through the precipitation method using calcium hydroxide and phosphoric acid as starting reactants. After drying, they were sintered at 1100 °C for 3 hours, and then bioactivity and osteoconductivity tests were carried out in simulated body fluid (SBF) and calvarial defect of New Zealand white rabbits, respectively. SBF exposure resulted in the deposition of a layer of carbonate apatite crystals on the surfaces of bicalcium phosphates but not on the hydroxyapatite. New bone forming capacity of the biphasic calcium phosphate with 60HAp:40?-TCP granules was the best, whereas that of the pure HAp was the worst. To this end, it can be concluded that the calcium phosphate with moderate biodegradability is good for producing good osteoconductivity.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"1 36","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114044503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Amorphous calcium polyphosphate (CPP) has potential as an implantable drug delivery matrix by virtue of a low temperature gelling protocol that has been shown to eliminate burst release and extend drug release time from the matrix. However, a greater understanding of this material’s interaction with aqueous environments is needed to more fully exploit this application. Variations in aqueous exposure were assessed using as-made amorphous CPP as well as CPP processed using established low temperature protocols. Solid-state 31P-NMR along with thermal and X-ray diffraction analyses were used to track resulting structural changes. Exposure to aqueous environments caused a reduction in CPP chain length that was dependant on gel time and mode of exposure. Significantly, increased gel times or water availability further resulted in crystallization events upon drying, except in the presence of a buffered solution. In general, drug elution studies showed an increase in the burst release of vancomycin from CPP disks gelled for extended periods, with matrix-water interactions appearing to be most influential during the drug loading stage. Overall, this study shows that CPP drug delivery matrices can be produced with tailored properties by closely controlling CPP-water interactions during processing.
{"title":"A Processing Approach to Tuning the Drug Delivery Characteristics of Calcium Polyphosphate Matrices","authors":"M. Filiaggi, N. Djogbenou, G. Hall","doi":"10.4303/BDA/D101101","DOIUrl":"https://doi.org/10.4303/BDA/D101101","url":null,"abstract":"Amorphous calcium polyphosphate (CPP) has potential as an implantable drug delivery matrix by virtue of a low temperature gelling protocol that has been shown to eliminate burst release and extend drug release time from the matrix. However, a greater understanding of this material’s interaction with aqueous environments is needed to more fully exploit this application. Variations in aqueous exposure were assessed using as-made amorphous CPP as well as CPP processed using established low temperature protocols. Solid-state 31P-NMR along with thermal and X-ray diffraction analyses were used to track resulting structural changes. Exposure to aqueous environments caused a reduction in CPP chain length that was dependant on gel time and mode of exposure. Significantly, increased gel times or water availability further resulted in crystallization events upon drying, except in the presence of a buffered solution. In general, drug elution studies showed an increase in the burst release of vancomycin from CPP disks gelled for extended periods, with matrix-water interactions appearing to be most influential during the drug loading stage. Overall, this study shows that CPP drug delivery matrices can be produced with tailored properties by closely controlling CPP-water interactions during processing.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123686729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xia Li, Koji Senda, A. Ito, Y. Sogo, and Atsushi Yamazaki
Difference in osteoclast responses (i.e., apoptosis, actin ring formation) to tricalcium phosphate (TCP) in culture medium supplemented with zinc and to zinc-containing tricalcium phosphate (ZnTCP) was investigated in this study. On the TCP ceramic, an increase in zinc ion in the culture medium within the range between 0.3 and 6.8 ppm significantly induced an increase in osteoclast apoptosis and a decrease in actin ring formation. However, even a high level of magnesium ion up to 100 ppm in the culture medium or up to 6.8mol% in the ceramic was unlikely to influence osteoclast activity. There was almost no significant difference in osteoclast apoptosis and actin ring formation between ZnTCP with 1mol% zinc and magnesiumcontaining tricalcium phosphate with 1.5mol% magnesium ceramic which have the same solubility and the same dissolution rate. It is suggested that only an increase in zinc level outside resorption lacuna has an inhibitory effect on osteoclast resorption and that an increase in zinc level inside resorption lacuna could not influence osteoclast activity.
{"title":"Difference in Osteoclast Responses to Tricalcium Phosphate in Culture Medium Supplemented with Zinc and to Zinc-Containing Tricalcium Phosphate","authors":"Xia Li, Koji Senda, A. Ito, Y. Sogo, and Atsushi Yamazaki","doi":"10.4303/BDA/D101106","DOIUrl":"https://doi.org/10.4303/BDA/D101106","url":null,"abstract":"Difference in osteoclast responses (i.e., apoptosis, actin ring formation) to tricalcium phosphate (TCP) in culture medium supplemented with zinc and to zinc-containing tricalcium phosphate (ZnTCP) was investigated in this study. On the TCP ceramic, an increase in zinc ion in the culture medium within the range between 0.3 and 6.8 ppm significantly induced an increase in osteoclast apoptosis and a decrease in actin ring formation. However, even a high level of magnesium ion up to 100 ppm in the culture medium or up to 6.8mol% in the ceramic was unlikely to influence osteoclast activity. There was almost no significant difference in osteoclast apoptosis and actin ring formation between ZnTCP with 1mol% zinc and magnesiumcontaining tricalcium phosphate with 1.5mol% magnesium ceramic which have the same solubility and the same dissolution rate. It is suggested that only an increase in zinc level outside resorption lacuna has an inhibitory effect on osteoclast resorption and that an increase in zinc level inside resorption lacuna could not influence osteoclast activity.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127190564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Munir, Xiang Li, M. Edirisinghe, W. Bonfield, M. Esat, J. Huang
Template-assisted electrohydrodynamic atomisation (TAEA) spraying of nanometer-sized siliconsubstituted hydroxyapatite (nanoSiHA) was used to pattern implant surfaces for guided cell growth to improve the repair and regeneration of medical implants. A suspension of nanoSiHA was prepared and characterized. Patterns of pillars and tracks of various dimensions were prepared using the suspension. It was found that the resolution of the pattern was affected by TAEA processing parameters, such as applied voltage, flow rate, distance between needle and substrate, and spray time. Fifteen minutes spraying time provided the most clear and uniform patterned topography with a distance between nozzle and substrate of 50mm and a flow rate of 4?l/min. Therefore, well-defined nanoSiHA patterns can be achieved by TAEA deposition, it thus offers great potential for patterning the surface of medical implants.
{"title":"Novel Patterning of Silicon-Substituted Hydroxyapatite","authors":"G. Munir, Xiang Li, M. Edirisinghe, W. Bonfield, M. Esat, J. Huang","doi":"10.4303/BDA/D101109","DOIUrl":"https://doi.org/10.4303/BDA/D101109","url":null,"abstract":"Template-assisted electrohydrodynamic atomisation (TAEA) spraying of nanometer-sized siliconsubstituted hydroxyapatite (nanoSiHA) was used to pattern implant surfaces for guided cell growth to improve the repair and regeneration of medical implants. A suspension of nanoSiHA was prepared and characterized. Patterns of pillars and tracks of various dimensions were prepared using the suspension. It was found that the resolution of the pattern was affected by TAEA processing parameters, such as applied voltage, flow rate, distance between needle and substrate, and spray time. Fifteen minutes spraying time provided the most clear and uniform patterned topography with a distance between nozzle and substrate of 50mm and a flow rate of 4?l/min. Therefore, well-defined nanoSiHA patterns can be achieved by TAEA deposition, it thus offers great potential for patterning the surface of medical implants.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115702786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muzafar A. Kanjwal, N. Barakat, F. A. Sheikh, H. Kim
First, electrospinning of colloidal solution consisting of titanium isopropoxide/poly(vinyl acetate) zinc nanoparticles has been achieved to produce polymeric nanofibers embedding solid nanoparticles. Calcination of the obtained electrospun nanofiber mats in air at 600 °C has been revealed to produce TiO2 nanofibers containing ZnO nanoparticles; ZnO-doped TiO2 nanofibers. The formed ZnO nanoparticles have been exploited as seeds to outgrow ZnO branches around the TiO2 nanofibers using a hydrothermal technique. As anode in lithium ion battery, the prepared nanostructure exhibited a high rate capacity of 1232 mAhg–1.
{"title":"Electrospun Titania Oxide Nanofibers Coupled Zinc Oxide Nanobranches as a Novel Nanostructure for Lithium Ion Batteries Applications","authors":"Muzafar A. Kanjwal, N. Barakat, F. A. Sheikh, H. Kim","doi":"10.4303/BDA/D110129","DOIUrl":"https://doi.org/10.4303/BDA/D110129","url":null,"abstract":"First, electrospinning of colloidal solution consisting of titanium isopropoxide/poly(vinyl acetate) zinc nanoparticles has been achieved to produce polymeric nanofibers embedding solid nanoparticles. Calcination of the obtained electrospun nanofiber mats in air at 600 °C has been revealed to produce TiO2 nanofibers containing ZnO nanoparticles; ZnO-doped TiO2 nanofibers. The formed ZnO nanoparticles have been exploited as seeds to outgrow ZnO branches around the TiO2 nanofibers using a hydrothermal technique. As anode in lithium ion battery, the prepared nanostructure exhibited a high rate capacity of 1232 mAhg–1.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"131 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128342541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Titanium and zirconium were immersed in Hanks’ solution with and without calcium and phosphate ions, and the surfaces were characterized with X-ray photoelectron spectroscopy (XPS) to determine the mechanism of calcium phosphate formation on titanium in simulated body fluids and in a living body. In addition, they were cathodically polarized in the above solutions. As a result, neither calcium nor phosphate stably exists alone on titanium, and calcium phosphate is naturally formed on it; calcium phosphate formed on titanium is stable and protective. On the other hand, calcium is never incorporated on zirconium, while zirconium phosphate, which is easily formed on zirconium, is highly stable and protective.
{"title":"Calcium Phosphate Formation on Titanium and Zirconium and Its Application to Medical Devices","authors":"T. Hanawa, Y. Tsutsumi","doi":"10.4303/BDA/D110119","DOIUrl":"https://doi.org/10.4303/BDA/D110119","url":null,"abstract":"Titanium and zirconium were immersed in Hanks’ solution with and without calcium and phosphate ions, and the surfaces were characterized with X-ray photoelectron spectroscopy (XPS) to determine the mechanism of calcium phosphate formation on titanium in simulated body fluids and in a living body. In addition, they were cathodically polarized in the above solutions. As a result, neither calcium nor phosphate stably exists alone on titanium, and calcium phosphate is naturally formed on it; calcium phosphate formed on titanium is stable and protective. On the other hand, calcium is never incorporated on zirconium, while zirconium phosphate, which is easily formed on zirconium, is highly stable and protective.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124630087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Ishikawa, T. Akasaka, S. Abe, Y. Yawaka, Masaya Suzuki, F. Watari
Imogolite is a naturally occurring aluminosilicate clay mineral with a nanotube structure. In this study, synthetic imogolite nanotubes were applied to cell culture and the properties as scaffold were compared with those of a conventional culture dish and the carbon nanotube scaffold. The surface characteristics of the imogolite scaffold were drastically changed with the amount of imogolite on the dish. Human osteoblast-like cells (SaOS2) on imogolite scaffolds showed a widely spreading morphology and a high functional expression. Particularly, the scaffold with the large amount of imogolite provided the suitable environments of topography, roughness, wettability and protein adsorption ability for widely spreading morphology and differentiation of osteoblasts. Imogolite retains various positive factors as scaffolds for osteoblastic proliferation and differentiation and is expected for the application to bone tissue engineering.
{"title":"Application of Imogolite, Almino-Silicate Nanotube, as Scaffold for the Mineralization of Osteoblasts","authors":"K. Ishikawa, T. Akasaka, S. Abe, Y. Yawaka, Masaya Suzuki, F. Watari","doi":"10.4303/BDA/D110133","DOIUrl":"https://doi.org/10.4303/BDA/D110133","url":null,"abstract":"Imogolite is a naturally occurring aluminosilicate clay mineral with a nanotube structure. In this study, synthetic imogolite nanotubes were applied to cell culture and the properties as scaffold were compared with those of a conventional culture dish and the carbon nanotube scaffold. The surface characteristics of the imogolite scaffold were drastically changed with the amount of imogolite on the dish. Human osteoblast-like cells (SaOS2) on imogolite scaffolds showed a widely spreading morphology and a high functional expression. Particularly, the scaffold with the large amount of imogolite provided the suitable environments of topography, roughness, wettability and protein adsorption ability for widely spreading morphology and differentiation of osteoblasts. Imogolite retains various positive factors as scaffolds for osteoblastic proliferation and differentiation and is expected for the application to bone tissue engineering.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125166148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Mavropoulos, M.L.F.M. Kede, N. D. C. Rocha, A. M. Costa, A. Tosi, M. H. P. D. Silva, A. Rossi
Synthetic hydroxyapatite was modified with zinc and strontium by two methods: ion exchange and coprecipitation synthesis. Hydroxyapatite and metal modified hydroxyapatite samples were characterized by XRD, ICP-OES, and FTIR-DRS. BSA adsorption experiments were accomplished during 24 hours using 1.0mg/mL of protein. UV spectrometry was used to quantify the protein at 278 nm. The results suggest that metal presence on the surface or in the bulk of hydroxyapatite improves the protein adsorption efficiency. FTIR-DRS showed that the protein main secondary structure ?-Helix is involved in the adsorption process.
{"title":"BSA Attachment on Apatite Surface Modified with Zn2+ and Sr2+","authors":"E. Mavropoulos, M.L.F.M. Kede, N. D. C. Rocha, A. M. Costa, A. Tosi, M. H. P. D. Silva, A. Rossi","doi":"10.4303/BDA/D101115","DOIUrl":"https://doi.org/10.4303/BDA/D101115","url":null,"abstract":"Synthetic hydroxyapatite was modified with zinc and strontium by two methods: ion exchange and coprecipitation synthesis. Hydroxyapatite and metal modified hydroxyapatite samples were characterized by XRD, ICP-OES, and FTIR-DRS. BSA adsorption experiments were accomplished during 24 hours using 1.0mg/mL of protein. UV spectrometry was used to quantify the protein at 278 nm. The results suggest that metal presence on the surface or in the bulk of hydroxyapatite improves the protein adsorption efficiency. FTIR-DRS showed that the protein main secondary structure ?-Helix is involved in the adsorption process.","PeriodicalId":127691,"journal":{"name":"Bioceramics Development and Applications","volume":"2012 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127382535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}