Contactless Laser-Assisted Patterning of Surfaces for Bio-Adhesive Microarrays

Abstract

Micropatterned surfaces with cell adhesive areas, delimited by protein repellent microstructures, are in high demand for its potential use as relevant biological assays. This is not only because such surfaces allow directing cell growth in a spatially localized and restricted manner, but also because they can be used to elucidate basic cell growth and orientation mechanisms. Here, it is presented a laser-assisted micropatterning technique to fabricate large area microstructures of poly (ethylene glycol) hydrogel onto a cell adhesive surface: a biofunctional maleic anhydride copolymer. By varying photoinitiator, laser intensity, copolymer as well as the hydrogel layer thickness, the optimum conditions to produce high quality features were found. The suitability of these micropatterned substrates for bioassay applications was proved by cell adhesion studies. The introduced procedure could be used to prepare a broad range of microarrays for certain bioanalytical approaches and to create different types of biofunctional surfaces.

Guidance of glial cells and neurites from dorsal root ganglia by laser induced periodic patterning of biphasic core/shell nanowires

“…Several top‐down and bottom‐up methods have been used to fabricate various surface patterns. Structuring of surfaces by lasers is one of the most preferred methods to pattern biomaterials because of its versatility and a non‐contact processing nature . Simply a laser beam can be focused on any substrate to create lines or holes directly onto the surface; however, such a direct writing process is slow and limited to create only a few types of structures.…”

Low-Power Laser Processing-Based Approach to Plasma Lithography for Cell Micropatterning

“…A pulsed laser is normally used for generating up to megawatt-class high power, which is required to process hard materials that are not cut by conventional machining process [18][19][20][21][22]. In laserbased micropatterning techniques that are not aimed at physically drilling the substrate because of their low power, various types of photosensitizers are employed to locally functionalize the substrate upon light excitation [23,24]. However, photosensitizers are in general not very biocompatible, and engineering of photosensitive materials requires dedicated chemistry [1].…”

Geometric Control of Cell Alignment and Spreading within the Confinement of Antiadhesive Poly(Ethylene Glycol) Microstructures on Laser-Patterned Surfaces

“…5 Recently, we reported a mask-less, laser-assisted micro lens array (MLA) patterning procedure to fabricate periodic protein and cell adhesive microdomains using inert poly(ethylene glycol) (PEG) microstructures on cell adhesive glass surfaces coated with maleic anhydride polymers. 6 In addition, PEG microstructures have been fabricated on silicon, glass, or poly-(dimethylsiloxane) surfaces modified with a 3-(trichlorosilyl) propyl methacrylate (TPM) monolayer, using mask-based photolithography, enabling cell adhesion onto the adhesive surfaces and minimal cell adhesion onto the PEG microstructures. 7a,b In principle, PEG microstructures are an effective barrier to protein adsorption and cell adhesion, since this well-established nontoxic and non-immunogenic polymeric material has been demonstrated to prevent nonspecific protein adsorption and unspecific prokaryotic and eukaryotic cell adhesion.…”

“…Cross-like patterns yielding square, rectangular and rhomboidal shaped celladhesive microdomains were obtained in few processing steps upon cross-linking by UV light induced free radical mechanism to form polymeric networks. 6 By changing the displacement distances and rotation angles before every subsequent laser exposure in the laser-assisted patterning procedure used, different geometries (square, rectangle or rhomboidal shaped) with a graded periodicity of 40, 60, 80, and 120 μm were fabricated to study the spatial confinement of cells in the adhesive areas and the geometric influence on cellular behavior.…”