Investigating the Use of Impedance Flow Cytometry for Classifying the Viability State of E. coli

Sensors

JulioCésar Franco¹  ChristianVinther Bertelsen¹  WinnieEdith Svendsen¹  Maria Dimaki¹  GustavErik Skands² 

[1] DTU Bioengineering, Technical University of Denmark, Søltofts Plads 221, 2800 Kgs. Lyngby, Denmark;SBT Instruments A/S, Symfonivej 37, 2730 Herlev, Denmark;

关键词: impedance spectroscopy;    impedance flow cytometry;    bacteria detection;    bacteria characterization;    bacteria inactivation;    lab-on-a-chip;   

DOI  :  10.3390/s20216339

来源: DOAJ

【 摘 要 】

Bacteria detection, counting and analysis is of great importance in several fields. When viability plays a major role in decision making, the counting of colony-forming units grown on agar plates remains the gold standard. However, because plate counts depend on the growth of the bacteria, it is a slow procedure and only works with culturable species. Impedance flow cytometry (IFC) is a promising technology for particle detection, counting and characterization. It relies on the perturbation of an electric field by particles flowing through a microfluidic channel. The perturbation is directly related to the electrical properties of the particles, and therefore provides information about their composition and structure. In this work we investigate whether IFC can be used to differentiate viable cells from inactivated cells. Our findings demonstrate that the specific viability state of the bacteria has to be considered, but that with proper characterization thresholds, IFC can be used to classify bacterial viability states. By using three different inactivation methods—ethanol, heat and autoclavation—we have been able to show that the impedance response of Escherichia coli depends on its viability state, but that the specific response depends on the inactivation method. With these findings we expect to be able to optimize IFC for more reliable bacteria detection and counting in the future.

【 授权许可】

Unknown