Simulated body fluid immersion

Filmon et al. (25) observed that modification of PHEMA through carboxymethylation with bromoacetic acid in alkaline medium induced considerable calcium deposition. For immersion in simulated body fluid (SBF), Miyazaki et al. (26) found that calcification was favorable in some circumstances when the polymer contained 20 and 50 mole% carboxyl groups. 

Cerutti, M.G. (2004) Characterization of bioactive glasses. Effect of the immersion in solutions that simulate body fluids. PhD Dissertation. University of Turin, Italy. 

Huang, X., Jiang, D., and Tan, S. (2004) Apatite formation on the surface of wol-lastonite/tricalcium phosphate composite immersed in simulated body fluid. J. Biomed. Mater. Res., 69 (1), 70-72. 

Figure 7.24 SEM images in backscattered electron (BSE) mode (a) and cathodolumines cence (CL) mode (b) of an APS hydroxyapatite coating immersed for 7 days in simulated body fluid (EHBSS) (Gotze, Hildebrandt...

Figure 2 shows the overall microstructure of the polished cross-section of the pseudowollastonite pellet after one month immersion in simulated body fluid and its relevant X-ray maps for silicon, calcium and phosphorous elements. This compositional microcharacterisation of the interface showed that the reaction zone was composed of two chemically dissimilar layers formed on the pseudowollastonite surface. The outer layer, with an average thickness of about 10 pm, was composed of a Ca0/P205-rich phase, identified as... 

Like in other bioactive glass-ceramics, when glass-ceramic A/W is immersed in simulated body fluid the same type of carbo-hydroxyapatite (CHA) layer is formed on the surface. The compositional and structural characteristics of this CHA layer are similar to those of the apatite in the natural bone and it s expected that osteoblast would proliferate on the surface of the CHA layer. This suggests that this CHA layer plays and essential role in forming the chemical bond of the glass-ceramics to the bone. 

Corrosion rate of immersed AZ91 Mg alloy and AZ91-FA nanocomposites in simulated body fluid as a function of immersion time (Razavi eta ., 2010). 

Tsuru et al. [87] reported that in PDMS-CaO-SiOj hybrids prepared by the sol-gel method, apatite appeared on their surfaces upon immersion into a simulated body fluid (SBF), which suggests that these hybrids can be bioactive. Similarly, Chen et al. [88] synthesized PDMS-CaO-SiO -TiOj hybrids and found that these systems show an apatite-forming ability, while being deformable. It was shown that PDMS-CaO-SiOj hybrids present apatite-forming ability when immersed in SBF and, moreover, these materials exhibit mechanical properties analogous to those of human cancellous bones. 

Salinas et al. [90] prepared CaO-SiOj-PDMS hybrid materials and their in vitro bioactivity was assessed by immersion into simulated body fluid (SBF). Due to their bioactivity and good mechanical properties, these materials could be used for soft tissue substitution or for coating metallic implants to damp the differences in rigidity of metal and bone. 

This assay was carried out soaking PDMS hybrids in Simulated Body Fluid [94], a solution with an inorganic ion concentration almost equal to blood plasma, buffered at pH 7.4. Samples with dimensions 10x10x2 mm were immersed into 40 mL of SBF at 37°C for 21 days. The samples were surface analyzed with Scanning Electron Microscopy and X-ray Energy Dispersion Spectroscopy (EDAX) in a JEOL 2000 Microscope (Tokyo, Japan), in an attempt to explore the possibility of formation of an apatite layer, being critical for improved biocompatibility of PDMS hybrids. 

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