Authors
Abstract
Novel hemostatic agents were prepared using (i) phosphoryl oligosaccharides of calcium (POs-Ca ® 45 and POs-Ca ® 50 with calcium contents being 4.5 and 5.0 mass %, respectively), (ii) sugar-containing hydroxyapatites (s-Ca10(PO4)6(OH)2; s-HAp) obtained by the hydrolyses of POs-Ca ® 45 and POs-Ca ® 50, respectively (s-HAp(45); Ca/P ratio = 1.56, 61.2 mass % HAp and 38.8 mass % organic materials and s-HAp(50); Ca/P ratio = 1.61, 79.3 mass % HAp and 20.7 mass % organic materials), and (iii) thermoplastic resin (random copolymer of ethylene oxide (EO) and propylene oxide (PO)) (EPO). The gels formed by mixing the EPO with water (EPO/water (mass ratio): 0.20) were freeze-dried at -50 ËšC for 15 h, and then blended with POs-Ca or s-HAp ((POs-Ca or s-HAp)/EPO-EO (mass ratio): 0.2). The noted findings due to the addition of POs-Ca or s-HAp to the composite gels were: (a) the stanching time of more than 80 min due to the addition of POs-Ca ® 50 to the composite gel with EPO : EO : water = 25 : 15 : 60 (mass ratio) (25EPO-15EO) and (b) formation of osteoid at the drilled hole within the tibia and femur of Japanese white rabbits due to the addition of s-HAp(45). The combined addition of POs-Ca and s-HAp to the EPO-EO were expected to enhance the hemostasis and bone regeneration.
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