Characterization of Surface Patterning on Polymer-Grafted Nanocubes Using Atomic Force Microscopy and Force Volume Mapping.

Atomic force microscopy (AFM), in particular force spectroscopy, is a powerful tool for understanding the supramolecular structures associated with polymers grafted to surfaces, especially in regimes of low polymer density where different morphological structures are expected. In this study, we utilize force volume mapping to characterize the nanoscale surfaces of Ag nanocubes (AgNCs) grafted with a monolayer of polyethylene glycol (PEG) chains. Spatially resolved force-distance curves taken for a single AgNC were used to map surface properties, such as adhesion energy and deformation.

Surface-Grafted Biocompatible Polymer Conductors for Stable and Compliant Electrodes for Brain Interfaces.

Durable and conductive interfaces that enable chronic and high-resolution recording of neural activity are essential for understanding and treating neurodegenerative disorders. These chronic implants require long-term stability and small contact areas. Consequently, they are often coated with a blend of conductive polymers and are crosslinked to enhance durability despite the potentially deleterious effect of crosslinking on the mechanical and electrical properties.

Self-assembly of nanocrystal checkerboard patterns via non-specific interactions.

Checkerboard lattices-where the resulting structure is open, porous, and highly symmetric-are difficult to create by self-assembly. Synthetic systems that adopt such structures typically rely on shape complementarity and site-specific chemical interactions that are only available to biomolecular systems (e.g.

Synthesis of PEDOT:PSS Brushes Grafted from Gold Using ATRP for Increased Electrochemical and Mechanical Stability.

We report PEDOT:PSS brushes grafted from gold using surface-initiated atom-transfer radical polymerization (SI-ATRP) which demonstrate significantly enhanced mechanical stability against sonication and electrochemical cycling compared to spin-coated analogues as well as lower impedances than bare gold at frequencies from 0.1 to 10 Hz. These results suggest SI-ATRP PEDOT:PSS to be a promising candidate for use in microelectrodes for neural activity recording.

The Modulation of Electrokinetic Streaming Potentials of Silicon-Based Surfaces through Plasma-Based Surface Processing.

A new plasma processing-based methodology for enhancing the streaming potential () that may be obtained in electrokinetic flows for a given pressure gradient over a silicon surface-based microchannel is indicated. The dependence of the on both the surface zeta potential and the electrolyte slip length was carefully determined through a series of experiments involving the variation of CF- and Ar-based plasma parameters, incorporating pressure, exposure time, and power. It was determined through analytical estimates that, while the zeta potential is always increased, the slip length may be diminished under certain conditions.