Multichannel Potentiostat/Galvanostat topologies
There is a multitude of scenarios that demand more than one channel of a potentio-/galvanostat. The reasons vary greatly – just to name a few typical settings:
- automating sequential multi-sensor probing over
- the need of scaling up experiments to more throughput via parallel experiments
- complex multi-electrode arrangements with need for specific synchronized control
- simultaneous comparison of a single or a set of test targets/sensors to a single or a group of reference sensors
As diverse as the reasons for using multichannel arrangements are the choices for solutions. In general, there are four basic approaches:
- multiple single-channel potentiostat / galvanostat
- multiplexing
- multi-potentio-/galvanostat
- poly-potentiostat
512 channel Potentiostat/Galvanostat for automated test and conditioning of electronic components
Nanoscale patterning of self-assembled monolayer (SAM)-functionalised substrates with single molecule contact printing
Defined arrangements of individual molecules are covalenty connected (“printed”) onto SAM-functionalised gold substrates with nanometer resolution. Substrates were initially pre-functionlised by coating with 3,3′-dithiodipropionic acid (DTPA) to form a self-assembled monolayer (SAM), which was characterised by atomic force microscopy (AFM), contact angle goniometry, cyclic voltammetry and surface plasmon resonance (SPR) spectroscopy. Pre-defined “ink” patterns displayed on DNA origami-based single-use carriers (“stamp”) were covalently conjugated to the SAM using 1-ethyl-3-(3-dimethylamino-propyl)carbodiimide (EDC) and N-hydroxy-succinimide (NHS). These anchor points were used to create nanometer-precise single-molecule arrays, here with complementary DNA and streptavidin. Sequential steps of the printing process were evaluated by AFM and SPR spectroscopy. It was shown that 30% of the detected arrangements closely match the expected length distribution of designed patterns, whereas another 40% exhibit error within the range of only 1 streptavidin molecule. SPR results indicate that imposing a defined separation between molecular anchor points within the pattern through this printing process enhances the efficiency for association of specific binding partners for systems with high sterical hindrance. This study expands upon earlier findings where geometrical information was conserved by the application of DNA nanostructures, by establishing a generalisable strategy which is universally applicable to nearly any type of prefunctionalised substrate such as metals, plastics, silicates, ITO or 2D materials.