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Identification of membrane antigens and measurement of their expression within a cell population is of fundamental importance to medical and biological studies. In this work, we present a cytometry approach that is based on magnetophoresis and distributed Coulter sensing in a microfluidic system. Our magnetophoretic cytometer offers quantitative analysis of cell membrane antigens on a portable and disposable platform compared to conventional flow cytometers, which are complex, expensive and large systems. Our tests with human breast cancer cells show the utility of our microfluidic device and its potential as a point-of-care instrument for biomedical testing.
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Microfluidic Bioelectrochemical Cell Platform for the Study of Extracellular Electron Uptake in Microbes
Miniaturization of measurement systems offers several advantages, including reduced sample and reagent volumes, improved control over experimental conditions, and the ability to multiplex complementary measurement modalities, thereby enabling new types of studies in microbial electrochemistry. We present a scalable glass-based microfluidic bioelectrochemical cell (µ-BEC) platform for multiplexed investigations of microbial extracellular electron uptake (EEU). The platform integrates eight independently addressable three-electrode cells in a 2×4 array, with transparent working electrodes that support simultaneous electrochemical analysis and optical imaging. Using Rhodopseudomonas palustris TIE-1 as a model phototroph, we measured EEU activity under light-dark cycling. Microfluidic flow was used to selectively remove planktonic cells, enabling isolation of the electron uptake signal associated with surface attached cells. These results demonstrate the µ-BEC as a robust and adaptable platform for probing microbial electron transfer, with broad potential for high-throughput and multimodal studies.
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- PAR ID:
- 10611368
- Publisher / Repository:
- Preprints.org
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript
- Posted Content:
- https://doi.org/10.20944/preprints202505.1879.v1
