Optimization, characterization and evaluation of ZnO/polyvinylidene fluoride nanocomposites for orthopedic applications: improved antibacterial ability and promoted osteoblast growth.

Herein, electrospun zinc oxide nanoparticle/poly (vinylidene fluoride) (ZnONP/PVDF) composite fiber membranes were designed, fabricated, and tested for improved orthopedic applications. A single factor screening study was conducted to determine the optimal ZnONP/PVDF formulation based on osteoblast (bone forming cells) proliferation and antibacterial properties. Further, ZnONP/PVDF materials were characterized for their morphology, crystallinity, roughness, piezoelectric properties, and chemistry to understand such cell results. The optimal concentration of high molecular weight PVDF (18%, w/v) and a low concentration of ZnONPs (1 mg/ml) were identified for electrospinning at room temperature in order to inhibit bacterial colonization (without resorting to antibiotic use) and promote osteoblast proliferation. Compared to no ZnO/PVDF scaffold without Piezo-excited group,the study showed that on the 1 mg/ml ZnO/PVDF scaffolds with piezo-excitation, the density of SA and E.coli decreased by 68% and 56%.The density of osteoblasts doubled within three days(compared to the control). In summary, ZnONP/PVDF composite fiber membranes were formulated by electrospinning showing an exceptional ability to eliminate bacteria colonization while at the same time promote osteoblast functions and, thus, they should be further studied for a wide range of orthopedic applications.

Advances in nanomedicine for the treatment of ankylosing spondylitis.

Ankylosing spondylitis (AS) is a complex disease characterized by inflammation and ankylosis primarily at the cartilage-bone interface. The disease is more common in young males and risk factors include both genetic and environmental. While the pathogenesis of AS is not completely understood, it is thought to be an immune-mediated disease involving inflammatory cellular infiltrates, and human leukocyte antigen-B27. Currently, there is no specific diagnostic technique available for this disease; therefore conventional diagnostic approaches such as clinical symptoms, laboratory tests and imaging techniques are used. There are various review papers that have been published on conventional treatment approaches, and in this review work, we focus on the more promising nanomedicine-based treatment modalities to move this field forward.

Dual targeting curcumin loaded alendronate-hyaluronan- octadecanoic acid micelles for improving osteosarcoma therapy.

INTRODUCTION: Curcumin (CUR) is a general ingredient of traditional Chinese medicine, which has potential antitumor effects. However, its use clinically has been limited due to its low aqueous solubility and bioavailability. In order to improve the therapeutic effect of CUR on osteosarcoma (i.e., bone cancer), a multifunctional micelle was developed here by combining active bone accumulating ability with tumor CD44 targeting capacity. METHODS: The CUR loaded micelles were self-assembled by using alendronate-hyaluronic acid-octadecanoic acid (ALN-HA-C18) as an amphiphilic material. The obtained micelles were characterized for size and drug loading. In addition, the in vitro release behavior of CUR was investigated under PBS (pH 5.7) medium containing 1% Tween 80 at 37℃. Furthermore, an hydroxyapatite (the major inorganic component of bone) affinity experiment was studied. In vitro antitumor activity was evaluated. Finally, the anti-tumor efficiency was studied. RESULTS: The size and drug loading of the CUR loaded ALN-HA-C18 micelles were about 118 ± 3.6 nm and 6 ± 1.2%, respectively. CUR was released from the ALN-HA-C18 micelles in a sustained manner after 12 h. The hydroxyapatite affinity experiment indicated that CUR loaded ALN-HA-C18 micelles exhibited a high affinity to bone. CUR loaded ALN-HA-C18 micelles exhibited much higher cytotoxic activity against MG-63 cells compared to free CUR. Finally, CUR loaded ALN-HA-C18 micelles effectively delayed anti-tumor growth properties in osteosarcoma bearing mice as compared with free CUR. CONCLUSION: The present study suggested that ALN-HA-C18 is a novel promising micelle for osteosarcoma targeting and delivery of the hydrophobic anticancer drug CUR.