An antibacterial platform based on capacitive carbon-doped TiO2 nanotubes after direct or alternating current charging

Abstract

Electrical interactions between bacteria and the environment are delicate and essential. In this study, an external electrical current is applied to capacitive titania nanotubes doped with carbon (TNT-C) to evaluate the effects on bacteria killing and the underlying mechanism is investigated. When TNT-C is charged, post-charging antibacterial effects proportional to the capacitance are observed. This capacitance-based antibacterial system works well with both direct and alternating current (DC, AC) and the higher discharging capacity in the positive DC (DC+) group leads to better antibacterial performance. Extracellular electron transfer observed during early contact contributes to the surface-dependent post-charging antibacterial process. Physiologically, the electrical interaction deforms the bacteria morphology and elevates the intracellular reactive oxygen species level without impairing the growth of osteoblasts. Our finding spurs the design of light-independent antibacterial materials and provides insights into the use of electricity to modify biomaterials to complement other bacteria killing measures such as light irradiation.

“Genetically Engineered” Biofunctional Triboelectric Nanogenerators Using Recombinant Spider Silk

“…Among other requirements, the urgent demand of drug‐free, electrical sterilization stands out to cope with the imprudent usage of antibiotics and drug resistance of microbial. A variety of electrical antibacterial techniques have been proven successful in research settings . However, none of them is viable for daily handling or proven effective for in vivo usage.…”

“…The post‐charging (triboelectric charged) RSSP patch builds potential difference between the bacteria and positively charged surface. Afterwards, extracellular electron transmission between the bacteria and RSSP patch impairs the morphology of bacteria and induces reactive oxygen species burst in the bacteria, contributing to post‐charging death of bacteria . Besides the electroporation, RSSP can also serve as the hosting matrix like other silk materials .…”

Corrosion Motivated ROS Generation Helps Endow Titanium with Broad‐Spectrum Antibacterial Abilities

“…Besides, it should steadily work. However, most available ROS generating systems must be activated by electric, ultraviolet or visible light, their ROS producing abilities will gradually fade away after the external supplier is turned off, limiting their application in clinic, since external stimuli can hardly pass through human tissue to reach the implant surfaces, so the ROS cannot continuously produced. Self‐motived ROS generation systems are therefore highly desirable.…”

Carbon/Graphene-Modified Titania with Enhanced Photocatalytic Activity under UV and Vis Irradiation

“…Some reports proposed that vis-responsive bactericidal activity of carbon-modified (mainly doped) titania [13,[73][74][75][76][77] was cased by the presence of carbon and the direct interaction (e.g., redox reaction) between photocatalyst and bacteria. Interestingly, Wang et al proposed that the electron transfer between C-doped titania nanotubes and bacteria induced the intracellular ROS formation and cell death, evaluated by charging of sample [78]. Moreover, Cruz-Ortiz et al reported that TiO 2 -rGO showed significant bactericidal activity (E. coli) under visible light irradiation, due to the generation of singlet oxygen [79].…”