To assess and evaluate Chitosan-Metamizole nanoparticles for fracture healing and analgesic potential, nanoparticles were formulated using the ionotropic gelation method. The nanoparticles were evaluated for particle size, zeta potential, polydispersity index, loading efficiency, surface characteristics and drug release properties. The analgesic activity was determined in carrageenan-induced arthritic male Wister rats. Further fracture healing potency, mechanical testing, radiographic examination and bone histology of the femur were studied. The drug loading efficiency of 11.38%-17.45%, particle size of 140-220 nm, and zeta potential of 19.12-23.14 mV were observed with a spherical, smooth appearance. Nanoparticles showed sustained release behaviour over a longer period. Nearly 4-fold inhibition of oedema was observed in animals treated with nanoparticles with excellent fracture healing potential. The femurs treated with nanoparticles required greater force to fracture. Nanoparticles significantly improved the strength and healing process. Histopathological studies showed the potential of nanoparticles in the healing process. The study confirmed the potential of nanoparticles in fracture healing and enhancement of analgesic activity.

中文翻译：

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壳聚糖-安乃近纳米颗粒对骨折愈合和镇痛作用的评估和评价：大鼠模型的临床前研究。

为了评估壳聚糖-安乃近纳米颗粒的骨折愈合和镇痛潜力，使用离子型凝胶法配制纳米颗粒。对纳米颗粒的粒径、zeta 电位、多分散指数、负载效率、表面特性和药物释放特性进行了评估。在角叉菜胶诱导的关节炎雄性 Wister 大鼠中测定镇痛活性。对股骨的骨折愈合效力、机械测试、放射线检查和骨组织学进行了进一步研究。载药量为11.38%-17.45%，粒径为140-220 nm，zeta电位为19.12-23.14 mV，外观呈球形、光滑。纳米颗粒表现出较长时间的持续释放行为。在用纳米粒子治疗的动物中观察到水肿抑制了近 4 倍，具有优异的骨折愈合潜力。用纳米粒子处理的股骨需要更大的力才能断裂。纳米颗粒显着改善了强度和愈合过程。组织病理学研究表明纳米粒子在愈合过程中的潜力。该研究证实了纳米颗粒在骨折愈合和增强镇痛活性方面的潜力。