Analytical Chemistry (prof. dr. M.W.F. Nielen)

1. Multiplex screening using planar arrays of color-encoded microspheres

Classical biorecognition based screening assays, such as ELISAs, measure only one type of biointeraction at a time. Suspension or planar arrays based on color-encoded microspheres allow parallel detection of multiple binding assays in a single well. This topic is being explored for multi-detection of mycotoxins in craft beers (PhD student Jeroen Peters). Alternatively, biorecognition can be exploited as a bioaffinity sample preparation tool, prior to mass spectrometric detection, as for example in the rbST screening and confirmatory analysis challenge (PhD student Nathalie Smits).

2. Advances in mass spectrometry

In 2018 a Horizon 2020 Marie Curie ITN project was granted that aims for the interfacing of immunoassays with direct ionization mass spectrometry. Flow injection electrospray ionization and DART ionization are explored for the rapid identification of lateral flow immunoassays (PhD student Ariadni Geballa Koukoula). In 2020, the Marie Curie ITN project MonPlas was granted that aims for the development of technologies to monitor concentrations of micro and nanoplastics in water for their presence, uptake and threat to animal and human life. In this project we will develop novel analytical workflows for the detection of micro and nanoplastics in foods (PhD student Clementina Vitali).

3. Smartphone-based food quality and safety testing

The Marie Curie Innovative Training Network FoodSmartphone [www.foodsmartphone.eu] proposes the development of smartphone-based (bio)analytical sensing and diagnostic tools, for simplified on-site pre-screening of quality and safety parameters and wireless data transfer to servers of relevant stakeholders. The consortium has been built upon highly complementary disciplines: (bio)analytical chemists, biologists, physicists, micro/nano-engineers, mathematicians, organic- and food chemists will work together on the joint supra-disciplinary goal. The scientific training in novel smartphone-based sensing technologies will have a major impact on future EU monitoring practices and, moreover, pave the road for Citizen Science. In one of the projects, multiplex smartphone assays for allergen detection have been designed for future self-testing by consumers. PhD student Gina Ross will graduate on March 12, 2021.

4. 'Proeftuin' Citizen Science.

• Citizen Science Living Lab - Health, Food and Environment applications

In 2017, the regional Citizen Science Innovation Initiative (CSII) has been established in which Radboud University Nijmegen, University of Twente and Wageningen University collaborate on health, food and environmental analytical chemistry with the ultimate aim of bringing the lab to the sample and facilitating future citizens science approaches. In 2018, the European Union through its European Fund for Regional Development (EFRO) and OP-Oost granted the project ‘Proeftuin Citizen Science’ (project no. PROJ-00748), coordinated by Radboud University. In this project, the academic CSII partners will validate and benchmark prototype devices and handhelds from six different private partners using their high-end facilities and expertise. The Laboratory of Organic Chemistry (ORC) is the academic partner from Wageningen University and will bring the expertise of its scientific staff and the technical skills of its technicians to the project. Particularly, high-end chromatography and spectroscopy for benchmarking of sensors, detailed characterization of sensor surfaces and translation of devices towards mobile and smartphone-based future alternatives is expected to be highly relevant. Further detailing of activities will depend on specific needs of the private partners in the project.

Recent publications:

A. Geballa-Koukoula, A. Gerssen, M.W.F. Nielen, “From smartphone lateral flow immunoassay screening to direct MS analysis: development and validation of a semi-quantitative Direct Analysis in Real Time Mass Spectrometric (DART-MS) approach to the analysis of deoxynivalenol”, Sensors, (2021) submitted.

P. de Haan, M.J.C. Santbergen, M. van der Zande, H. Bouwmeester, M.W.F. Nielen, E. Verpoorte, “A versatile, compartmentalised gut-on-a-chip system for pharmacological and toxicological analyses”, Sci. Rep., (2021) in press.

G.M.S. Ross, D. Filippini , M.W.F. Nielen, G.IJ. Salentijn, “Unraveling the hook effect; a comprehensive study of high antigen concentration effects in sandwich lateral flow immunoassays“, Anal. Chem., 92 (2020) 15587−15595.

G.M.S. Ross, D. Filippini , M.W.F. Nielen, G.IJ. Salentijn, “Interconnectable solid-liquid protein extraction unit and chip-based dilution for multiplexed consumer immunodiagnostics “, Anal. Chim. Acta, 1140 (2020) 190-198.

A. Geballa-Koukoula, A. Gerssen, M.W.F. Nielen, “Direct analysis of lateral flow immunoassays for deoxynivalenol using electrospray ionization mass spectrometry“, Anal. Bioanal. Chem., 412 (2020) 7547–7558.

M.J.C. Santbergen, M. van der Zande, A. Gerssen, H. Bouwmeester, M.W.F. Nielen, “Dynamic in vitro intestinal barrier model coupled to chip-based liquid chromatography mass spectrometry for oral bioavailability studies“, Anal. Bioanal. Chem., 412 (2020) 1111-1122.

F.A.M.G. van Geenen, F.W. Claassen, M.C.R. Franssen, H. Zuilhof, M.W.F. Nielen, “Laser Ablation Electrospray Ionization Hydrogen/Deuterium Exchange Ambient Mass Spectrometry Imaging“, J. Am. Soc. Mass Spectrom., 31 (2020) 249-256.

M.H. Blokland, A. Gerssen, J. Jager,  M.W.F. Nielen, “Ionization source, functional combination with a mobile device and arrangement with an atmospheric inlet mass spectrometry system“, European Patent Application (2020), EP20177574.