Electrochemical detection
Signal detection occurs directly in the chip, by virtue of integrated micro-electrodes. The outcome of enzymatic substrate transformation is an electro-active product, which is measured by redox-cycling on the electrodes. The system makes use of conventional enzymes, such as horse radish peroxidase (HRP) or alkaline phosphatase (ALP).
Electrochemical detection offers several advantages over absorbance measurements:
The detected current is proportional to the analyte concentration (as opposed to depending on a total number of molecules, as is the case with luminescence measurement). Therefore, the response obtained in a miniaturized system is identical to that obtained in large volumes, and detection limits are readily brought to the pico-molar level in the micro-devices.
Moreover, electrochemical detection is not influenced by matrix opacity, which is particularly advantageous for direct measurements in serum, urine, CSF, and other matrixes.
Benefits
Reduced time-to-result: A full assay can be performed in 10-15 minutes due to the small reaction volume, and the particular design of the chips.
Convenience: Pocket-sized cartridges, handled with a minimum of care, are adapted to low sample and reagent consumption.
Cost-efficiency: Minimal reaction chamber volume implies >10-fold reduction in ELISA kit reagent consumption which results in the most competitive data-point pricing.
DiagnoSwiss chips: Biosensors for ultra-fast ELISA
Biosensor-Chip is the core element of diagnoSwiss technology. This consumable chip, which emanated from the combination of microfluidics and electrochemistry technologies, is a revolutionary device which is easily amenable to a wide range of analytical applications.
DiagnoSwiss chips are factually polymer cartridges with an array of micro-cells designed for running magnetic bead-based ELISA protocols with standard immunology reagents.
The micro-cells, with incorporated electrodes for electrochemical readout of enzymatic reactions, are suited for manual or automated use. With incubation times adapted to assay kinetics, beads and reagents are greatly pre--concentrated to yield results in the pg/ml range.