Organic/Inorganic bioactive materials Part III: in vitro bioactivity of gelatin/silicocarnotite hybrids

Abstract

Abstract:In this work we present our experimental results on synthesis, structure evolution and in vitro bioactivity assessment of new gelatin/ silicocarnotite hybrid materials. The hybrids were obtained by diluting gelatin (G) and silicocarnotite (S) ceramic powder with G:S ratios of 75:25 and 25:75 wt.% in hot (40 o C) water. The hybrids were characterized using XRD, FTIR, SEM/EDS and XPS. FTIR depicts that the "red shift" of amide I and COO -could be attributed to the fact that the gelatin prefers to chelate Ca 2+ from S. The growth of calcium phosphates on the surface of the hybrids synthesized and then immersed in 1.5 SBF for 3 days was studied by using of FTIR, XRD and SEM/EDS. According to FTIR results, after an immersion of 3 days, A and B-type CO 3 HA can be observed on the surface. XRD results indicate the presence of hydroxyapatite with well defined crystallinity. SEM/EDS of the precipitated layers show the presence of CO 3 HA and amorphous calcium phosphate on the surface of samples with different G/S content when immersed in 1.5 SBF. XPS of the G/S hybrid with 25:75 wt.% proved the presence of Ca-deficient hydroxyapatite after an in vitro test for 3 days. Warsaw and Springer-Verlag Berlin Heidelberg. © Versita

Hydroxyapatite and tricalcium phosphate composites with bioactive glass as second phase: State of the art and current applications

“…The high glass/gel reactivity and its strong tendency to crystallize may induce both the transformation of HA into TCP phases and the formation of silicates, such as wollastonite, pseudowollastonite, and silicocarnotite, depending both on the glass/gel percentage in the samples and on the thermal treatment employed to sinter them. The development of such silicates is not detrimental, because the bioactivity of these phases, although it is not as high as that of their parent bioglass, has been confirmed by several investigators . When the samples are soaked in SBF, the apatite precipitation on their surface starts in those areas which contain the most soluble phase of silicon.…”

“…The development of such silicates is not detrimental, because the bioactivity of these phases, although it is not as high as that of their parent bioglass, has been confirmed by several investigators. [282][283][284][285][286][287] When the samples are soaked in SBF, the apatite precipitation on their surface starts in those areas which contain the most soluble phase of silicon. What is remarkable to note in terms of bioactivity is the synergistic effect occurring between the glass and HA, since the composites show a faster bioactive behaviour than the glass and HA considered separately.…”

<i>In </i><i>V</i><i>itro</i>Bioactivity of Collagen/Calcium Phosphate Silicate Composites, Cross-Linked with Chondroitin Sulfate

“…This band does not undergo the "red shift" after in vitro test in 1.5 SBF for 3 days, i. e. (COO) 2 Ca bond does not observe. The band at 1646 cm -1 (for the two composites) and at 1558 (1553) cm -1 can be assigned to the amide I and amide II from the collagen [12,13]. From the depicted FTIR results are visible that amide I underdoes the "blue shift" from ~1612cm -1 (Fig.…”

“…Analysis for the collagen -as has been written, the band at 1340 cm -1 (curve b) in collagen represents not only the COO -, but a number of bands in the range 1400-1300 cm -1 , which are attributed to the presence of type I collagen in biological tissue [13]. This band does not undergo the "red shift" after in vitro test in 1.5 SBF for 3 days, i. e. (COO) 2 Ca bond does not observe.…”

“…We observed that the prepared ceramics were in vitro bioactive for different periods of time. On this base we have prepared in vitro bioactive composites with some biodegradable polymers without [12][13][14][15] and with [16] cross-linkage.…”