Microfluidic-based analytical systems

Using fabrication techniques originally developed for microelectronics, networks of fluidic channels can be created. We employ this technology to produce small-scale devices for detection of pathogens and other analytes of interest. Our fabrication technologies include photolithography, softlithography and nanoimprinting technology. An outstanding micromill allows us to do rapid prototyping and to create complex microfluidic structures either directly in polymer substrates or within metal templates. Laser scribing is another technology we can employ for the generation of larger microchannels as well as for the development of laser-scribed graphene electrodes(LIG). These are highly porous graphitic electrodes made on polyimide foils with interesting electrochemical characteristics. Similarly, laser-induced carbon nanofibers are produced – checkout out section on nanofibers for more information. 

Our initial work focused on the development of platform technologies for pathogen detection using microTotal Analysis Systems (lab-on-a-chip) strategies. Most recently, we have demonstrated how LIG electrodes can easily be integrated into microfluidics, liposomes enable multiplexing, electrochemiluminescence can further lower the limits of detection. Currently, we are putting special emphasis on sample preparation strategies in microfluicic systems and on capillary-driven approaches to further support point-of-care diagnostics. Similarly, we have studied paper-based systems and combined them with chemiluminescence detection to enable low limits of detection with very simple rapid systems. 

For example:

• Hermann, C.A., Mayer, M., Griesche, C., Beck, F., Baeumner, A.J. “Microfluidic-enabled magnetic labelling of nanovesicles for bioanalytical applications” Analyst (2021) 146: 997 – 1003, https://doi.org/10.1039/D0AN02027C
• Griesche, C., Hoecherl, K., Baeumner, A.J. “Substrate-Independent Laser-Induced Graphene Electrodes for Microfluidic Electroanalytical Systems” ACS Applied NanoMaterials (2021) 3114 – 3121, http://dx.doi.org/10.1021/acsanm.1c00299
• Beck, F., Horn, C., Baeumner, A.J., “Dry-reagent microfluidic biosensor for simple detection of NT-proBNP via Ag nanoparticles” Analytica Chimica Acta, (2021) 1191, 339375, https://doi.org/10.1016/j.aca.2021.339375
• Wang, Y, Rink, S, Baeumner, A.J., Seidel, M. “Microfluidic flow-injection aptamer-based chemiluminescence platform for sulfadimethoxine detection” Microchimica Acta (2022), 189, 117, https://doi.org/10.1007/s00604-022-05216-6
• Gerstl, F., Pongkitdachoti. U., Unob, F. and Baeumner, A.J. “Miniaturized Sensor for Electroanalytical and Electrochemiluminescent Detection of Pathogens enabled through Laser-Induced Graphene Electrodes embedded in Microfluidic Channels” Lab on a Chip (2022) 22, 3721 – 3733, https://doi.org/10.1039/D2LC00593J
• Fenzl, C., Nayak, P., Hirsch, T., Wolfbeis, O.S., Alshareef, H.N., Baeumner, A.J. “Laser-scribed graphene electrodes for aptamer-based biosensing”, DOI: 10.1021/acssensors.7b00066
• Reinholt, S., Behrent, A., Greene, C., Kalfe, A., Baeumner, A.J. “Isolation and Amplification of mRNA within a Simple Microfluidic Lab on a Chip” Anal. Chem vol. 86(1), pp. 849 - 856 (2014), DOI: 10.1021/ac403417z, http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3923508/
• Wongkaew, N., He, P., Kurth, V, Surareungchai,W., Baeumner, A.J. “Multi-channel PMMA microfluidic biosensor with integrated IDUAs for electrochemical detection” Anal. Bioanal. Chem. Vol 405 (18), pp. 5965 – 5974 (2013), DOI: 10.1007/s00216-013-7020-0
• Nugen, S.R., Asiello, P.J., Connelly, J.T., Baeumner, A.J. “PMMA biosensor for nucleic acids with integrated mixer and electrochemical detection” Biosensors and Bioelectronics, vol. 24, pp. 2428 – 2433 (2009), DOI: 10.1016/j.bios.2008.12.025
• Bunyakul, N., Edwards, K.A., Promptmas, C., Baeumner, A.J. “Cholera toxin subunit B detection in microfluidic devices” Analytical and Bioanalytical Chemistry, vol. 393(1), p. 177 – 186, Special anniversary issue. (2009), DOI: 10.1007/s00216-008-2364-6
• Kwakye, S.B. and Baeumner, A.J. “An Embedded System for Portable Electrochemical Detection” Sensors and Actuators B, vol. 123, pp. 336 – 343 (2007), DOI: 10.1016/j.snb.2006.08.032
• Kevin P. Nichols, Julia R. Ferullo, Antje J. Baeumner “Recirculating, passive Micromixer with a novel sawtooth Structure” Lab-on-Chip, vol. 6(2) pp. 242 - 246 (2006), DOI: 10.1039/B509034B
• Natalya V. Zaytseva, Richard A. Montagna, and Antje J. Baeumner “Microfluidic biosensor for the serotype-specific detection of Dengue virus” Analytical Chemistry, vol. 77, p. 7520 – 7527 (2005), DOI: 10.1021/ac0509206