Micropatterning

Karthaus, O., Terayama, T. and Hashimoto, Y. (2006) Selective dewetting of polymers on metal/silicon micropatterns. e-J. Surf. Sci. Nanotechnol., 4, 656-660. 

Karthaus, O., Adachi, C., Arakaki, S., Endo, A. and Wada, T. (2006) Preparation of micropatterned organic light emitting diodes by self-organization. Mol. Cryst., Liq. Cryst., 444, 87-94. 

Mossman, K. and Groves, J. (2007) Micropatterned supported membranes as tools for quantitative studies of ihe immunological synapse. Chem. Soc. Rev., 36. 46-54. 

Kim, C. Burrows, P. E. Forrest, S. R. 2000. Micropatterning of organic electronic devices by cold-welding. Science 288 831-833. 

DG Lidzey, MS Weaver, MA Pate, TA Fisher, DDC Bradley, and MS Skolnick, Photoprocessed and micropatterned conjugated polymer LEDs, Synth. Met., 82 141-148, 1996. 

Fig. 5 Schematic cross-sections of thin film morphologies of the topographic pattern grown by a graphoepitaxy method. A micropattern with different lamellar domain orientation is shown, a Surface-parallel lamellae, typical of film thickness t greater than the natural equilibrium period Lq. b Surface-perpendicular lamellae, typical of film thickness t less than L0. (adapted from [41])...

Fig. 7 Novel patternable block copolymers to achieve spatially controlled nanostructures, a An asymmetric PaMS-fc-PHS copolymer/photoacid generator/crosslinker solution was spin-coated on a silicon substrate and formed vertical PaMS cylinders due to rapid solvent evaporation, b 248 nm stepper exposure and subsequent development to form micropatterns with features as small as 400 nm. c Strong UV irradiation under high vacuum to remove PaMS, thus generating patterned nanochannels...

Bioadhesion is an area of research important in the selection of biomaterials (e.g., for implants). It is also critical in the development of the new biofouling coatings. A system for bioadhesion studies was developed, in which silicones with chemically and topologically (microengineered) modified surfaces were evaluated in the studies of the response to such surfaces of a diverse set of organisms.559-561 A new study of micropatterning and surface modification of PDMS to control bioadhesion has been reported.562... 

Niu, Z., et al., Electrophoretic build-up of alternately multilayered films and micropatterns based on graphene sheets and nanoparticles and their applications in flexible supercapacitors. Smaii, 2012. 8(20) p. 3201-3208. 

For non-suspension cultures, suitable matrices include liquid overlay on agarose (59), Matrigel , or Cultrex (48, 92). More recently, micropatterned arrays have been developed for adherent 3-D spheroid cultures (56) and have been used to show reduced chemosensitivity of colorectal carcinoma cells to irinotecan (58). In some cases, 3-D cultures can be enhanced by the addition of host cells. This increases complexity, but inevitably decreases flexibility and speed of analysis. However, important insights into the role of host cells have emerged stromal cells modify the gene expression and response of many tumor cell types to chemotherapeutic agents (93) and tumor-associated myofibroblasts can enhance tumor invasiveness (94). 

A two-dimensional micropatterned tissue can be easily obtained by utihz-ing the inherent differences in cell adhesiveness between different micropatterned photografted regions. This was attained by photoiniferter graft polymerization with a projection mask placed on an iniferter-derivatized surface. Since protein adsorption and cell adhesion are markedly suppressed on nonionic graft polymers, such as polyDMAm, any anchorage-dependent cells such as endothelial cell adhere and proliferate only on nonirradiated surfaces, resulting in the formation of a two-dimensional patterned tissue or cellular sheet (Fig. 24). 

Fig. 24 Micropatterned tissue photomask used for regional differential non-cell and cell adhesiveness (A) and the patterned endothelial tissue (B). Photoiniferter polymerization occurs only on photoirradiated regions, which is non-cell-adhesive...

Fig. 25 Schematic diagram of the presentation of a regionally specific micropatterned surface with an unprecedented five different photograft-copolymerized regions using the comhination of a photomask and an X-Y step motor-controUed stage...

Mayer, M., et al. (2004) Micropatterned agarose gels for stamping arrays of proteins and gradients of proteins. Proteomics. 4, 2366-76. 

A very important factor is the length scale of surface structures and their shape. This becomes obvious when looking at the spreading of a liquid on surfaces with a micropatterned heterogeneity [246,258,259],... 

J. T. Groves, N. Ulman, and S. G. Boxer, Micropatterning fluid lipid bilayers on solid supports Science 275, 651-653 (1997). 

In addition to conventional photoresist polymers, Langmuir-Blodgett (LB) films and SAMs [79-81] have been used as resists in photolithography. In such applications, photochemical oxidation, cross-linking, or generation of reactive groups are used to transfer micropatterns from the photomask into the mono-layers [82-84]. 

Photolithography using gray-scale photomasks enables the generation of micropatterns that have multilevel and curved features on photoresist upon a single exposure [363]. 

There are several recent examples of the switching of nonspecific protein binding on polymer surfaces by application of an external stimulus. Alexander and coworkers demonstrated that protein adhesion can be controlled on PNIPAM surface brushes [14, 181]. For instance, it was reported that the adsorption of FITC-labeled bovine serum albumin (FITC-BSA) on PNIPAM/hexadecanethiol micropatterned surfaces could be tuned by LCST. However, this effect was found to be less pronounced after prolonged incubation times or repeated heating/cooling cycles. The authors suggested that this behavior could be due to unspecific PNIPAM-protein interactions [14],... 

Hold on at the Right Spot Bioactive Surfaces for the Design of Live-Cell Micropatterns... 

Keywords Assay Bioactive surface Cell adhesion Cell chip Hydrogel Microengineering Micropattern Peptide Polymer brush Protein adsorption... 

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