Laminin coated diamond electrodes for neural stimulation.

The performance of many implantable neural stimulation devices is degraded due to the loss of neurons around the electrodes by the body's natural biological responses to a foreign material. Coating of electrodes with biomolecules such as extracellular matrix proteins is one potential route to suppress the adverse responses that lead to loss of implant functionality. Concurrently, however, the electrochemical performance of the stimulating electrode must remain optimal to continue to safely provide sufficient charge for neural stimulation.

Minimal attachment of to DNA modified surfaces.

Extracellular deoxyribonucleic acid (eDNA) exists in biological environments such as those around medical implants since prokaryotic or eukaryotic cells can undergo processes such as autolysis, necrosis, and apoptosis. For bacteria, eDNA has been shown to be involved in biofilm formation and gene transfer and acts as a nutrient source. In terms of biofilm formation, eDNA in solution has been shown to be very important in increasing attachment; however, very little is known about the role played by surface immobilized eDNA in initiating bacterial attachment and whether the nature of a DNA layer (physically adsorbed or covalently attached, and molecular weight) influences biofilm formation.

Controlled Attachment of Pseudomonas aeruginosa with Binary Colloidal Crystal-Based Topographies.

Micro- and nanotopographies can interfere with bacteria attachment, however, the interplay existing between surface chemistry and topography remains unclear. Here, self-assembled spherical micrometer- silica and nanometer poly(methyl methacrylate) (PMMA)-sized particles are used to make binary colloidal crystal (BCC) topographical patterns to study bacterial attachment. A uniform surface chemistry of allylamine plasma polymer (AAMpp) is coated on the top of the BCCs to study only the topography effects.

Tuning the Density of Poly(ethylene glycol) Chains to Control Mammalian Cell and Bacterial Attachment.

Surface modification of biomaterials with polymer chains has attracted great attention because of their ability to control biointerfacial interactions such as protein adsorption, cell attachment and bacterial biofilm formation. The aim of this study was to control the immobilisation of biomolecules on silicon wafers using poly(ethylene glycol)(PEG) chains by a "grafting to" technique. In particular, to control the polymer chain graft density in order to capture proteins and preserve their activity in cell culture as well as find the optimal density that would totally prevent bacterial attachment.

Colloidal crystal based plasma polymer patterning to control Pseudomonas aeruginosa attachment to surfaces.

Biofilm formation on medical implants and subsequent infections are a global problem. A great deal of effort has focused on developing chemical contrasts based on micro- and nanopatterning for studying and controlling cells and bacteria at surfaces. It has been known that micro- and nanopatterns on surfaces can influence biomolecule adsorption, and subsequent cell and bacterial adhesion.

Self-assembled binary colloidal crystal monolayers as cell culture substrates.

This study investigated the formation of self-assembled binary colloidal crystal (BCC) monolayers using evaporation induced confined area assembly (EICAA), and fabricated a family of various BCCs for cell culture. A library of various BCCs with different structures was established and it was demonstrated that after stabilisation the BCCs have potential to be used as substrates with well-ordered surface topographies and chemistries for manipulating cell-surface interactions. Three cell types including MG63 osteoblasts, L929 fibroblasts, and primary human adipose-derived stem cells (hADSCs) show different responses on selected surfaces (either between BCCs or BCCs vs.