Taking a Stab at Microbes

Arrays of tiny, rigid, and sharp pillars mimic natural antimicrobial surfaces by binding and breaking bacterial cells open

photonic devices, Micro-lens, mosquito-borne infections, Microbiota, bone repair, 3D printing, neurodegenerative disease, cancer treatments, biological research, sepsis, foot and mouth disease, cytometry, batteries, Influenza A virus, vascular diseases, New Cancer Drugs, RNA molecules, polymers, antimicrobial resistance, Aging White Blood Cells, microviscosity, Transplant Drug, Nanophotonics, photonics, Built-In Nanobulbs, cerebral cortex, cancer cells, nanowires, optoelectronic, solar energy, gold nanowires, Chikungunya virus, concrete, glaucoma, light-emitting diode, Proteomics, nanostructures, nickel catalyst, Ultrafast lasers, liver capsular macrophages, obesity, cancer, lignin polymer, liver capsular macrophages, Ultrafast lasers, monocyte cells, cancer treatments, antibody drug, gene mutations, quantum-entangled photons, gut microbes, skin aging, stroke, machine learning, Cloned tumors, cancer, Rare Skin Disease, terahertz lasers, silicon-nanostructure pixels, oral cancer, heart muscle cells, cancer, cancer stem cells, gastric cancer, microelectromechanical systems, data storage, silicon nanostructures, Drug delivery, cancer, muscle nuclei, Lithography, silicon nanostructures, Quantum matter, robust lattice structures, potassium ions, Photothermal therapy, Photonic devices, Optical Components, retina, allergy, immune cells, catalyst, Nanopositioning devices, mold templates, lung cancer, cytoskeletons, hepatitis b, cardiovascular disease, memory deficits, Photonics, pre-eclampsia treatment, hair loss, nanoparticles, mobile security, Fluid dynamics, MXene, Metal-assisted chemical etching, nanomedicine, Colorectal cancer, cancer therapy, liver inflammation, cancer treatment, Semiconductor lasers, zika virus, catalysts, stem cells, fetal immune system, genetic disease, liver cancer, cancer, liver cancer, RNA editing, obesity, Microcapsules, genetic disease, Piezoelectrics, cancer, magnesium alloy, Quantum materials, therapeutic antibodies, diabetes, 2D materials, lithium-ion batteries, obesity, lupus, surfactants, Sterilization, skin on chip, Magnetic Skyrmions, cyber-security, wound infections, human genetics, immune system, eczema, solar cells, Antimicrobials, joint disorder, genetics, cancer

A powerful solution to the global spread of antimicrobial resistance could soon become available, thanks to A*STAR researchers, who have come up with a physical and green alternative to biochemically active antibacterial agents.

Typically transmitted by contact with contaminated surfaces, bacterial infections pose serious health threats in medical settings. Small molecular antibacterial agents, which are commonly used in antiseptics, disinfectants, and preservatives, and other consumer care products, can prevent cross-infection by annihilating bacteria on frequently touched surfaces. However, their overuse contributes to antimicrobial resistance. These toxic and persistent substances can also harm the environment by disrupting the ecological balance of soils and endangering aquatic life.

In response to this, Yugen Zhang and Yuan Yuan, from the Institute of Bioengineering and Nanotechnology have developed nanostructured surfaces that destroy bacteria through physical, rather than biochemical interactions¹. These surfaces mimic the antimicrobial patterns formed by ultra-small pillars on cicada wings. “In addition to being clean and safe, this technology does not require externally applied chemicals,” says Zhang.

The researchers added a zinc-based solution to various surfaces, including rubber, glass, wood, and metal foil, then immersed the surfaces in an aqueous solution containing amine-rich 2-methylimidazole to form a so-called zeolitic imidazolate framework coating. The coating consisted of an array of tiny, positively charged dagger-like crystals that grew perpendicularly to the substrates.

“We used inexpensive materials and a simple method to create this nano-dagger structure on different types of surfaces,” says Zhang noting that his team had to try numerous formulas before finding the right growth conditions.

Regardless of the coated substrate, the nano-dagger arrays effectively killed the antibiotic-resistant bacteria Escherichia coli and Staphylococcus aureus as well as the fungus Candida albicans, demonstrating their broad applicability. They also retained their antibacterial activity when exposed four consecutive times to E. coli over two months, proving their durability.

According to Zhang, the positive charges positioned on the nano-daggers first attract bacterial cells that bear negatively charged membranes, making them stick to the coated surface. Next, the sharp nano-dagger tips rip the cell membranes open through electrostatic and gravitational forces.

“We are really excited about the excellent bacterial killing property of this technology and believe that it will have wide-ranging applications in real life,” says Zhang. His team is currently working on developing nano-dagger surface prototypes and other antimicrobial nano-patterned surfaces using different materials.

The A*STAR-affiliated researchers contributing to this research are from the Institute of Bioengineering and Nanotechnology.

Source : A*STAR Research