Helium beam shadowing for high spatial resolution patterning of antibodies on microstructured diagnostic surfaces

Abstract

We have developed a technique for the high-resolution, self-aligning, and high-throughput patterning of antibody binding functionality on surfaces by selectively changing the reactivity of protein-coated surfaces in specific regions of a workpiece with a beam of energetic helium particles. The exposed areas are passivated with bovine serum albumin (BSA) and no longer bind the antigen. We demonstrate that patterns can be formed (1) by using a stencil mask with etched openings that forms a patterned exposure, or (2) by using angled exposure to cast shadows of existing raised microstructures on the surface to form self-aligned patterns. We demonstrate the efficacy of this process through the patterning of anti-lysozyme, anti-Norwalk virus, and anti-Escherichia coli antibodies and the subsequent detection of each of their targets by the enzyme-mediated formation of colored or silver deposits, and also by binding of gold nanoparticles. The process allows for the patterning of three-dimensional structures by inclining the sample relative to the beam so that the shadowed regions remain unaltered. We demonstrate that the resolution of the patterning process is of the order of hundreds of nanometers, and that the approach is well-suited for high throughput patterning.

Bacterial Patterning: A Promising Biofabrication Technique

“…89 Furthermore, bacterial cells adhere to these specific areas through receptor−ligand binding, hydrophobic interactions, and/or electrostatic interactions. 90,91 However, photolithography has certain shortcomings for bacterial patterning. Nonuniform surface modification and heterogeneous bacterial adhesion may lead to decreased spatial resolution.…”

“…In general, the target substrate is coated with photosensitive bacterial adhesion substances, which undergo UV-triggered photo-cross-linking or photodegradation with the assistance of photomasks . Furthermore, bacterial cells adhere to these specific areas through receptor–ligand binding, hydrophobic interactions, and/or electrostatic interactions. , However, photolithography has certain shortcomings for bacterial patterning. Nonuniform surface modification and heterogeneous bacterial adhesion may lead to decreased spatial resolution .…”

Antimicrobial nanospheres thin coatings prepared by advanced pulsed laser technique

“…In the past years a series of papers have been published in prestigious journals highlighting the relevance of magnetite nanostructures in preventing the development of microbial biofilm and the opportunity of utilizing these nanosystems to obtain improved, antimicrobial coatings for biomedical applications [ 7 – 8 ]. Nonpolar functionalized magnetite nanostructures alone [ 9 – 10 ] or combined with different natural products, such as usnic acid (UA) [ 11 ] or essential oils ( Mentha piperita [ 12 ], Anethum graveolens [ 13 ], Salvia officinalis [ 14 ], Eugenia carryophyllata [ 15 ]), showed improved antibiofilm effects on different types of microbial strains. Usually, these types of phyto-nano-coatings have been applied to a variety of medical surfaces in order to improve their resistance to microbial colonization [ 16 ].…”