Magazine 01/2023

The UpTurn project is a response to the trends towards miniaturization and multitasking in electrochemistry. The aim of the project is to develop microfluidic platforms that can be used in electrochemical research.

Microfluidics is a field of science investigating processes and technologies for handling liquids in volumes in range of nano- to microliters. Thanks to the small volumes, precise control and manipulation of liquids is possible on a scale where surface forces prevail over volumetric ones. Microfluidics covers a wide spectrum of research applications and is firmly embedded in the trends towards miniaturization and automation of systems. Microfluidic tools have been progressively implemented in many laboratories, including electrochemical ones. The miniaturized electrochemical platforms help to achieve high repeatability of results and integrate many elements to create intelligent multi-task electrochemical analysis platforms.

Microfluidics and electrochemistry are fields of science which can be combined. Microfluidics rely on miniaturized devices and can be integrated in many stages of research work. Although the electrochemical methods are not as sensitive at detection as fluorescence or mass spectrometry, but can be easily miniaturized without losing analytical performance. Importantly, using smaller electrodes and lower electrolyte volumes can result in better sensitivity due to reduced parasitic effects and mass transport limitations.

Further, thin-film electrodes with thickness in nanometer range and homogeneous morphology can be implemented in microfluidic devices. Typical microelectrode structures (single electrode or electrode arrays) can be developed by modification of the geometry or the electrode surface with nanomaterials to obtain high analytical performance. Thereby, it is possible to develop a wide range of sensors, miniaturized fuel cells, as well as perform complex analyses of electrochemical reactions etc.

The main element developed in UpTurn project is a microflow chip, where microelectrodes are integrated inside the microchannels and microchambers. It is compatible with analytical devices such as UV-Vis spectrophotometer and Raman spectrometers. The adaptation of such systems will accelerate research work by allowing for multiple electrochemical experiments and parallel analyses to be carried out in tandem. In addition, through miniaturization the consumption of chemical reagents will be significantly reduced. The platform address a wide range of applications and markets, e.g., in sensors and fuel cells.

Presently, electrochemical microfluidic chips are being tested in our laboratories, among others their electrochemical stability and repeatability are defined. The aim of this stage of research is to develop robust technologies for microfluidic electrochemical chips and test a range of selected, emerging (spectro) electrochemical applications.

Current Opinion in Electrochemistry 2019, 15:175–185