Category: Reports

Hi, my name is Gabriel Werr (ESR 8) and I am researching “Microfluidic methods for bead-based assays on-chip” as well as on-chip sensing methods at Uppsala University.

My colleague Mara Lucchetti (ESR 12) is researching the integration of iPSC-derived epithelial cells and on-chip TEER (transepithelial electrical resistance) measurements in the HuMiX gut model. Together we have been developing Platinum thin-film electrodes that can be integrated into her existing HuMiX model without compromising the seal of her chip.

The goal of my secondment at University of Luxembourg was to set up the new TEER electrodes for continuous readout of up to eight sensors. This included choosing a suitable electrical connection method that can be sterilised while not being too time consuming during assembly, and in order to read out the eight sensors continuously a multiplexer was set up together with an automation script that switches and logs all the sensors.
Due to COVID-19 restrictions we had to resort to video conferences and exchanging samples and prototypes by mail.

With my engineering background it was very useful to learn about all the small hurdles that need to be considered when implementing new equipment in a cell experiment to make it actually usable and convenient. Mara has done a great job providing me that insight even with the added difficulty of the entire secondment being held online.

Hi, my name is Mara Lucchetti (ESR 12) and I am researching the “Integration of iPSC-derived epithelial cells and of on-chip TEER measurement in the HuMiX gut model” at the University of Luxembourg.

The human-microbial cross talk (HuMiX) platform has been developed by Paul Wilmes’ laboratory at the University of Luxembourg in order to study the molecular interactions between the host and microbes under biomimetic conditions. Throughout the years, the HuMiX gut-on-a-chip model has undergone several modifications in order to provide a representative model of the gastrointestinal-microbe environment. The most recent version, being HuMiX 3.0, has in contrast to the previous versions an additional nitrogen (N₂) channel, which enables to recreate an anoxic (deficient in oxygen) environment for culturing representative bacterial species from the gut.

The secondment at Uppsala University (UU) from 17 February to 13 March has been planned as part of the EUROoC training program in order to integrate a TEER (transepithelial electrical resistance) measurement system in HuMiX 3.0 to monitor gut epithelial barrier function. During my secondment, Gabriel and myself successfully designed and fabricated thin-film Pt electrodes. These sensors will first be tested in a demonstration prototype before being integrated in HuMiX. Unfortunately, my secondment had to be interrupted due to the COVID-19 crisis. Hence, Gabriel and myself will perform some preliminary tests individually. A second stay at Uppsala University will be planned to complete the project.

Given that I have a biomedical background, I am grateful that I had the opportunity to collaborate with Gabriel and his group at UU to get an insight into microfabrication techniques. Finally, I want to thank Gabriel and his colleagues for their warm welcome and for introducing me to the Swedish culture.