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In this work, novel magnetic nanocomposite-bonded metalloporphyrins were synthesized by an effective silanation approach between 3-aminopropyltriethoxysilane derivatized metalloporphyrins and silica-coated magnetic Fe₃O₄ nanoparticles. The initial metalloporphyrin derivatives were synthesized by the amidation reaction of metalloporphyrin acyl chloride with 3-aminopropyltriethoxysilane. After the metalloporphyrin derivatives were adsorbed on the surface of silica-coated magnetic Fe₃O₄ nanoparticles, the solid mixture was heated under vacuum at 110 °C for 3 h and then thoroughly washed with chloroform. The obtained magnetic nanocomposite-bonded metalloporphyrins were characterized by elemental analyzer, low-temperature N₂ adsorption (BET method), transmission electron microscopy, UV-vis spectroscopy, and infrared spectroscopy. Interestingly, using this particular silanation method, metalloporphyrins could be quantitative-immobilized in magnetic nanocomposites by controlling the input ratio of metalloporphyrins and silica-coated magnetic Fe₃O₄ nanoparticles. The excellent catalytic activity and recyclability of the magnetic nanocomposite-bonded metalloporphyrins were demonstrated in the cyclohexane oxidation with iodosylbenzene.

We reported previously that a bioactive PMMA-based cement was obtained by using a dry method of silanation of AW-GC particles, and using high molecular weight PMMA beads. In this report, commercial PMMA bone cements (CMW1, Surgical Simplex) containing AW-GC filler in the ratio of 70wt% were investigated (abbreviated as B-CMW1 and B-Surg Simp). Their handling properties were similar to the commercial CMW1 cement that does not contain bioactrve powder (C-CMW1) as dough and setting times were 3 and 8 minutes respectively for both types of bioactive cements compared to 2 and 6 minutes respectively for C-CMW1. Bending strength of plates made from both bioactive cements and C-CMW1 cement was 90 ± 7 MPa for B-CMW1 and 98 ± 7 MPa for B-Surg Simp compared to 92±6 MPa for C-CMW1 after one day of immersion in simulated body fluid (SBF). These cements were also implanted in the medullary canals of rat tibiae. After 4 and 8 weeks of implantation, the bone-cement interface was examined using scanning electron microscope and Giemsa surface staining and the affinity index was calculated. After 8 weeks it was 55.5±10.8 for B-CMW1 and 49.4 ± 4.6 for B-Surg Simp compared to 2.0±1.4 for C-CMW1 indicating higher bioacivity than that previously reported.