Reagents were generated locally on an array of eight individually addressable electrodes in order to modify self‐assembled monolayers. Since the array was manufactured in a soft polymer material, it can have mechanical contact with a delicate sample without inducing defects. Lengthy leveling procedures are not necessary and the scan times can be shortened.

a b s t r a c tSoft linear gold microelectrode arrays for high throughput scanning electrochemical microscopy (SECM) imaging were fabricated using the Aerosol Jet Ò printing technology. Nanoparticulate gold ink was printed on polyimide Kapton HN Ò thin films. After sintering, a 200 nm thick Parylene C coating was deposited to cover and seal the gold tracks. A cross-section of the array of microelectrodes was exposed by laser cutting using an ArF excimer laser beam directed onto a metallic mask. Cyclic voltammograms, approach curves and SECM images in feedback mode demonstrate the capability of the arrays as SECM probes. Reactivity imaging of a platinum band structure on glass was performed with Parylene C coating facing the substrate providing an almost constant working distance. The softness of the array leads to a bending and allows scanning in contact mode like brushing the sample surface. For hard surfaces such as array electrode structures and similar materials, this occurs without detectable damage to the sample.

Self‐assembled monolayers (SAMs) of oligoethylene glycol (OEG)‐terminated alkanethiolates on gold, which are used to control protein adsorption and cell adhesion, were patterned by reaction with Br2/HOBr electrogenerated at a microelectrode of a scanning electrochemical microscope (SECM). The spreading of the Br2 diffusion layers was limited by a homogeneous reaction with cystamine or L‐cystine as scavengers. The influence of process parameters on the patterning process was explored by simulation and combinatorial experiments. The experimental determination of pattern sizes from SECM feedback images was verified by scanning force microscopy. The simulation considered the local Br2 formation as well as Br2 consumption in the reaction with the OEG SAM, by reduction at the gold substrate, and by the homogeneous scavenging reaction. It used experimentally determined diffusion coefficients and rate constants of the scavenging reaction. and Experiments and simulation confirmed the existence of regions in the parameter space, in which the patterning process is robust against small variation of the parameters working distance, pulse time and scavenger excess.

Control of the cell adhesion and growth on chemically patterned surfaces is important in an increasing number of applications in biotechnology and medicine, for example implants, in-vitro cellular assays, and biochips. This review covers patterning techniques for organic thin films suitable for site-directed guidance of cell adhesion to surfaces. Available surface patterning techniques are critically evaluated, with special emphasis on surface chemistry that can be switched in time and space during cultivation of cells. Examples from the authors' laboratory include the use of cell-repellent self-assembled monolayers (SAM) terminated by oligoethylene glycol (OEG) units and the lifting of the cell repellent properties by use of electrogenerated Br2/HOBr which can be performed with positionable microelectrodes. Structural changes of the SAM were analyzed by polarization-modulated infrared reflection absorption spectroscopy (PM IRRAS). Use of a soft array system of individually addressable microelectrodes enables formation of flexible and complex patterns in a short time and has the potential for further acceleration of probe-induced local manipulation of cell adhesion.

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