The present work focused on developing an innovative composite material by reinforcing polymer matrix with highly porous activated charcoal. Polyvinyl alcohol-activated charcoal（PVA-AC） composite scaffolds were deve...The present work focused on developing an innovative composite material by reinforcing polymer matrix with highly porous activated charcoal. Polyvinyl alcohol-activated charcoal（PVA-AC） composite scaffolds were developed by varying the AC concentrations（0, 0.5, 1, 1.5, 2 and 2.5 wt%） in PVA matrix by freeze drying method. The developed scaffolds were characterized for their physicochemical, mechanical and in-vitro biological properties. In addition, the effect of AC on the attachment, proliferation and differentiation of osteoblast MG 63 cells was evaluated by scanning electron microscopy（SEM）, 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay, alkaline phosphatase（ALP） activity assay and alizarin red stain-based（ARS） assay. All the PVA-AC composite scaffolds exhibited good bioactivity, hemocompatibility and protein adsorption properties. The scaffolds with high AC concentration（2.5 wt%） showed controlled drug release kinetics that are suitable for long term healing. The mechanical properties of all the PVA-AC composite scaffolds were improved when compared to the pure PVA scaffold. The high porosity, swelling degree and hydrophilicity of PVA-AC composite scaffolds facilitated cell attachment and proliferation. This is due to porous AC present in the sample that supported the osteoblast differentiation and formed mineralized nodules without the addition of any extra agents. From the above studies, it can be concluded that PVA-AC composite scaffolds are promising biomaterials for bone tissue engineering applications.展开更多
Cold atmospheric plasmas are widely used in biomedicine.Although direct plasma treatments of wounds have been demon-strated,there are still obstacles hampering further clinical adoption,for example,the limited treatme...Cold atmospheric plasmas are widely used in biomedicine.Although direct plasma treatments of wounds have been demon-strated,there are still obstacles hampering further clinical adoption,for example,the limited treatment area,inconsistent ac-tions and risk of thermal injury.In this respect,plasma-activated air(PAA)is proposed and demonstrated for infected wounds treatment as an alternative to the conventional direct plasma treatment.The combination of gliding arc discharge reactor and dielectric barrier discharge reactor produces highly bioactive PAA.In in vitro sterilisation of Staphylococcus aureus,approxi-mately 9-log reduction is achieved after the PAA treatment for 6 min.Bovine serum albumin is added to the S.aureus sus-pension to further simulate the wound exudate to accomplish inactivation of approximately 3-log reduction after 10 min.In vivo experiments show that the PAA treatment of infected wounds significantly reduces the bacterial load and improves the healing rate,revealing an optimal treatment time of 3 min/day.The immunohistochemical and blood biochemical analyses show that the PAA-3 min treatment enhances wound healing by inhibiting the tissue inflammatory response and inducing growth factor production without showing evident systemic toxicity.In conclusion,PAA holds great clinical promise as a safe and effective wound-healing strategy.展开更多
基金the Department of Biotechnology and Medical Engineering, The National Institute of Technology
文摘The present work focused on developing an innovative composite material by reinforcing polymer matrix with highly porous activated charcoal. Polyvinyl alcohol-activated charcoal（PVA-AC） composite scaffolds were developed by varying the AC concentrations（0, 0.5, 1, 1.5, 2 and 2.5 wt%） in PVA matrix by freeze drying method. The developed scaffolds were characterized for their physicochemical, mechanical and in-vitro biological properties. In addition, the effect of AC on the attachment, proliferation and differentiation of osteoblast MG 63 cells was evaluated by scanning electron microscopy（SEM）, 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay, alkaline phosphatase（ALP） activity assay and alizarin red stain-based（ARS） assay. All the PVA-AC composite scaffolds exhibited good bioactivity, hemocompatibility and protein adsorption properties. The scaffolds with high AC concentration（2.5 wt%） showed controlled drug release kinetics that are suitable for long term healing. The mechanical properties of all the PVA-AC composite scaffolds were improved when compared to the pure PVA scaffold. The high porosity, swelling degree and hydrophilicity of PVA-AC composite scaffolds facilitated cell attachment and proliferation. This is due to porous AC present in the sample that supported the osteoblast differentiation and formed mineralized nodules without the addition of any extra agents. From the above studies, it can be concluded that PVA-AC composite scaffolds are promising biomaterials for bone tissue engineering applications.
基金supported by National Natural Science Foundation of China(Grant 52277231)City University of Hong Kong Donation Research(Grant DON-RMG 9229021)Hong Kong PDFS—RGC Postdoctoral Fellowship Scheme(PDFS2122-1S08).
文摘Cold atmospheric plasmas are widely used in biomedicine.Although direct plasma treatments of wounds have been demon-strated,there are still obstacles hampering further clinical adoption,for example,the limited treatment area,inconsistent ac-tions and risk of thermal injury.In this respect,plasma-activated air(PAA)is proposed and demonstrated for infected wounds treatment as an alternative to the conventional direct plasma treatment.The combination of gliding arc discharge reactor and dielectric barrier discharge reactor produces highly bioactive PAA.In in vitro sterilisation of Staphylococcus aureus,approxi-mately 9-log reduction is achieved after the PAA treatment for 6 min.Bovine serum albumin is added to the S.aureus sus-pension to further simulate the wound exudate to accomplish inactivation of approximately 3-log reduction after 10 min.In vivo experiments show that the PAA treatment of infected wounds significantly reduces the bacterial load and improves the healing rate,revealing an optimal treatment time of 3 min/day.The immunohistochemical and blood biochemical analyses show that the PAA-3 min treatment enhances wound healing by inhibiting the tissue inflammatory response and inducing growth factor production without showing evident systemic toxicity.In conclusion,PAA holds great clinical promise as a safe and effective wound-healing strategy.
