Optical and impedimetric study of genetically modified cells for diclofenac sensing

Kai Ostermann,Margarita Guenther,Gerald Gerlach,Stefan Görlandt,Steffen Herbst,Ingo Tobehn-Steinhäuser,Gerhard Rödel,Falko Altenkirch

doi:10.5194/jsss-8-215-2019

Abstract

Abstract. Whole-cell biosensors, based on genetically modified yeast cells, were employed to detect anthropogenic micropollutants (e.g. drugs). Specific stimuli, e.g. traces of drugs, lead to the induction of fluorescence in the respective cells. Receptors of the cells detect specific signal molecules and induce the formation of fluorescent proteins. In this work, genetically modified cells of the yeast Saccharomyces cerevisiae BY4741 were confined in a four-chamber microfluidic cell, providing an optical monitoring of the cell behaviour and their supply with the nutrients. The measurements of the time-dependent fluorescence intensity were performed with different concentrations of the drug diclofenac, and the sensitivity of yeast cells to diclofenac was demonstrated. Cell viability was monitored by simultaneous impedance recording.

Highlights

Anthropogenic micropollutants such as drugs are often barely removed in water treatment plants, eventually entering the water cycle
Two chambers of the upper part were connected to a pump and served for the nutrient or measuring solution supply with a rate of 20 μL min−1
Two chambers of the upper part were connected to a pump and served for the supply of nutrient (MM in the reference channel) and measuring solution

Summary

Introduction

Anthropogenic micropollutants such as drugs are often barely removed in water treatment plants, eventually entering the water cycle. There are very accurate and reliable analytical methods available for the detection of diclofenac in surface water, e.g. liquid chromatography–tandem mass spectrometry (Hernando et al, 2006; Ferrer-Aguirre et al, 2016), highresolution mass spectrometry with liquid chromatography (Richardson and Ternes, 2014), gas chromatography–mass spectrometry (Deng et al, 2003), or ultra performance liquid chromatography (Nováková et al, 2006; Petrie et al, 2015) They require time-consuming and costly sampling and subsequent analysis in laboratory environment and necessitate special laboratories with appropriate staff and logistical efforts. Small, sensitive, robust, and online capable biosensors are needed for on-site applications (Steinke et al, 2018; Rau et al, 2014)

Methods

Results

Conclusion