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Published on: November 23, 2015
A Label-Free Cell-Based Biosensor Method for Ethanol Quantification Using Temperature-Induced Spontaneous Cell
Derick Yongabi1, Alex Krane1, Heloisa Espreafico Guelerman Ramos2
1Laboratory for Soft Matter and Biophysics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium.
Biosensors
|July 27, 2026
Summary
A new cell-based biosensor offers rapid, low-cost ethanol quantification using a label-free heat transfer method (HTM). This innovative approach monitors yeast detachment, providing a dual-function assay for both ethanol concentration and cell quality.
Area of Science:
- Biotechnology and Bioengineering
- Biosensor Technology
- Chemical Sensing
Background:
- Existing ethanol quantification methods are often costly, require reagents or labels, or involve extensive sample preparation.
- There is a need for rapid, low-cost, and label-free biosensors for diverse applications including quality control and biofuel production.
- Saccharomyces cerevisiae (yeast) behavior is sensitive to ethanol concentration, offering potential for biosensing applications.
Purpose of the Study:
- To introduce a novel, purely cell-based, label-free biosensor for rapid and low-cost ethanol quantification.
- To exploit temperature-gradient-induced yeast detachment as a readout mechanism for ethanol concentration.
- To demonstrate the biosensor's potential for assessing microbial cell quality and drug screening.
Main Methods:
- Development of a biosensor utilizing Saccharomyces cerevisiae detachment from a chip surface induced by a temperature gradient.
- Monitoring of cell detachment kinetics via time-resolved changes in interfacial thermal resistance using the heat transfer method (HTM).
- Quantification of ethanol by measuring the detachment half-time (t_d50) after pre-exposing yeast cells to varying ethanol concentrations (0-70% v/v).
Main Results:
- The biosensor exhibited a pronounced non-monotonic detachment half-time (t_d50) response to ethanol, peaking around 20% v/v.
- Detachment half-time increased from ~45 min (0% ethanol) to over 10 hours (20% ethanol), decreasing thereafter, with no detachment at 60% ethanol.
- The assay demonstrated dual functionality, with fresh yeast responding up to ~50% ethanol and aged yeast ceasing detachment above ~8% ethanol.
Conclusions:
- The developed cell-based, label-free biosensor provides a compact, low-cost, and rapid strategy for ethanol sensing.
- The platform shows promise for real-time monitoring of microbial cell quality and label-free drug screening applications.
- The unresolved non-monotonic effect of ethanol on yeast detachment warrants further fundamental investigation.
