| AVS 62nd International Symposium & Exhibition | |
| Biomaterial Interfaces | Wednesday Sessions |
| Session BI-WeA |
| Session: | Biophysics, Membranes and Nanoscale Biological Interfaces |
| Presenter: | Graham Leggett, University of Sheffield, UK |
| Authors: | A. Johnson, University of Sheffield, UK P.M. Chapman, University of Sheffield, UK A.M. Alswieleh, University of Sheffield, UK P. Bao, University of Leeds, UK A. Tsargorodska, University of Sheffield, UK S.P. Armes, University of Sheffield, UK S.D. Evans, University of Leeds, UK G.J. Leggett, University of Sheffield, UK |
| Correspondent: | Click to Email |
We describe simple routes to the fabrication of corrals, channels, traps and other structures for the fabrication of spatially organized lipid bilayers and membrane proteins. These utilize photochemistry and polymer brushes. In the first approach, UV exposure of films of (chloromethylphenyl)trichlorosilane (CMPTS) causes dehalogenation of the surface creating carboxylic acid groups to create hydrophilic, anionic regions, in which lipid mobilities are observed that are similar to those observed on glass surfaces. In masked regions, the halogen remains intact, and is used to grow poly(oligoethyleneglycol methacrylate) (POEGMA) brushes by atom-transfer radical polymerization (ATRP), defining lipid-free walls within which SLBs may be formed by vesicle fusion. Two-component structures are fabricated by using an aminosilane film in which the amine group is protected by a photoremovable nitrophenyl group. Selective exposure, through a mask or using a Lloyd’s mirror interferometer, causes patterned deprotection of the film leading to patterned brush growth by ATRP. Poly(Cysteine methacrylate) (PCysMA) is a new, highly biocompatible, stimulus-responsive zwitterionic polymer that forms thick brushes when grown from surfaces by atom transfer radical polymerization (ATRP). Lipid mobility similar to that observed on glass is observed on PCysMA brushes. Measurements of membrane protein diffusion have been made using ac trap structures. After lithographic definition of corrals, channels and other structures, PCysMA is end-capped and the remainder of the surface deprotected; POEGMA brushes are grown by ATRP, enclosing the PCysMA structures. Using interferometric lithography, arrays of close-packed gold nanostructures may be defined on the substrate. These are strongly coupled to photosynthetic membrane proteins, yielding intense extinction spectra. These gold nanostructures are incorporated into brush corrals and other structures, with polymer brushes grown to the same height as the gold nanostructures, enabling the formation of a continuous SLB with integral plasmonic reporters for membrane protein activity.