RESUMO
For the first time, the influence of different types of atoms (Zn and O) on the antibacterial activities of nanosized ZnO was quantitatively evaluated with the aid of a 3D-printing-manufactured evaluation system. Two different outermost atomic layers were manufactured separately by using an ALD (atomic layer deposition) method. Interestingly, we found that each outermost atomic layer exhibited certain differences against gram-positive or gram-negative bacterial species. Zinc atoms as outermost layer (ZnO-Zn) showed a more pronounced antibacterial effect towards gram-negative E. coli (Escherichia coli), whereas oxygen atoms (ZnO-O) showed a stronger antibacterial activity against gram-positive S. aureus (Staphylococcus aureus). A possible antibacterial mechanism has been comprehensively discussed from different perspectives, including Zn(2+) concentrations, oxygen vacancies, photocatalytic activities and the DNA structural characteristics of different bacterial species.
Assuntos
Antibacterianos/química , Oxigênio/química , Óxido de Zinco/química , Zinco/química , Antibacterianos/farmacologia , Escherichia coli/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos da radiação , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Microscopia de Força Atômica , Impressão Tridimensional , Rodaminas/química , Espectrofotometria Ultravioleta , Staphylococcus aureus/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/efeitos da radiação , Raios Ultravioleta , Óxido de Zinco/farmacologiaRESUMO
Cubic Cu2O nanoparticle modified hydrogel (CMHG) was synthesized to address two major problems (harmful irradiation and high density pathogens) of the current light-emitting screens simultaneously. The as-prepared hydrogel could conveniently form an adjustable semitransparent film over various shaped screens to provide enhanced antibacterial activity and longer Cu2O service life. More importantly, with the aid of cubic Cu2O nanoparticles, the energy of the harmful blue light irradiation could be effectively transformed into a photocatalysed power source to sterilize the surface of the screen. This low toxic CMHG showed no significant influence on the touch control experience, and had obvious eye protective effects, which thus offered a convenient manner to protect vision and sterilize touch screens at the same time.
RESUMO
Inspired from dandelion, dual-layered ZnO nanoarrays were modified on the surface of 3D printing implants to reduce the postoperation infective rate. According to both in vitro and in vivo tests, it exhibited unique two model-releasing features which could be applied to 3D printing implants as a healthier alternative to antibiotics.
RESUMO
Green fuel-driven thumb sized motors (TSM) were designed and optimized by 3D printing to explore their in-situ remediation applications in rare studied underwater area. Combined with areogel processing and specialized bacteria domestication, each tiny TSM could realize large area pollutant treatment precisely in an impressive half-automatically manner.
RESUMO
Herein, a highly customized and broad-spectrum antibacterial implant was prepared through the combination of 3D printing technology and surface nano-modification. The antibacterial coating, which consists of the film-forming agent polyvinyl alcohol (PVA), polyethylene acid (PAA), and green-synthesized silver nanoparticles (Ag-NPs), was modified on the surface of a 3D-printed implant. The small-sized Ag-NPs (<10 nm) showed potent broad spectrum activity and good biocompatibility in relatively low concentration. Moreover, through changing the content of the Ag-NPs and the proportion of PVA and PAA, the loadings and release rate of Ag-NPs could be controlled according to actual requirements, achieving the goal of precise treatment. Animal experiments demonstrated that the implant system exhibited superior anti-infection performance, which could effectively reduce the postoperative infection risk of implant materials, consequently promoting the practical process of 3D printed implants.
RESUMO
Exemplified with jackfruit and sugarcane, natural extracted aerogels with inherent structural anisotropy were investigated for the first time. With the help of nano-modification, the dual liquid/current directing capability of the Ag decorated jackfruit aerogel was discovered. This interesting material was then applied as the core component of a 3D printed wearable device for intelligent wound management. The as-prepared ultra-light (<10 g) wearable device could provide drainage diversion, wound warning and triple antibacterial treatment in a continuous and automatic manner.
RESUMO
Assisted by three-dimensional printing technology, we proposed and demonstrated a full spectrum visible light activated antibacterial system by using a combination of 500 nm sized Cu2O crystals and light-emitting diode (LED) lamps. Further improved antibacterial ratios were achieved, for the first time, with pure Cu2O for both Gram-positive bacteria and Gram-negative bacteria among all of the six different color LED lamps. For practical antibacterial applications, we revealed that the nonwoven fabric could act as excellent carrier for Cu2O crystals and provide impressive antibacterial performance. Furthermore, integrated with our self-developed app, the poly(ethylene terephthalate) film loaded with Cu2O crystals also showed significant antibacterial property, thus making it possible to be applied in field of touch screen. The present research not only provided a healthier alternative to traditional ultraviolet-based sterilization but also opened an auto-response manner to decrease the rate of microbial contamination on billions of touch screen devices.
Assuntos
Antibacterianos/farmacologia , Cobre/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/efeitos da radiação , Computadores , Cobre/farmacologia , Cobre/efeitos da radiação , Humanos , Luz , Impressão Tridimensional , Difração de Raios XRESUMO
The first visible three-mode switchable antibiotic nanocomposite, including "Packaged" (low toxicity and high stability), "On" (potent antibacterial activity, including drug-resistant strains) and "Off" (easy separation) modes, was synthesized to address several problems caused by antibiotic abuses. Some potential applications were discussed by using animal experiments and 3D printing separately.
RESUMO
For the first time, homogeneous and well-ordered functional nanoarrays were grown densely on the complex structured three-dimensional (3D) printing frameworks through a general plasma enhanced atomic layer deposition (PEALD) assisted hydrothermal surface engineering process. The entire process was free from toxic additives or harmful residues and, therefore, can meet the critical requirements of high-purity products. As a practical example, 3D customized earplugs were precisely manufactured according to the model of ear canals at the 0.1 mm level. Meanwhile, well-ordered ZnO nanoarrays, formed on the surfaces of these 3D printed earplugs, could effectively prevent the growth of five main pathogens derived from the patients with otitis media and exhibited excellent wear resistance as well. On the basis of both animal experiments and volunteers' investigations, the 3D customized earplugs showed sound insulation capabilities superior to those of traditional earplugs. Further animal experiments demonstrated the potential of as-modified implant scaffolds in practical clinical applications. This work, exemplified with earplugs and implant scaffolds, oriented the development direction of 3D printing in biomedical devices, which precisely integrated customized architecture and tailored surface performance.