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Updated: Jan 23, 2026

Preparation and Application of a New Bacterial Biosensor for the Presumptive Detection of Gunshot Residue
Published on: May 9, 2019
Portable and low-cost biosensor towards on-site detection of diclofenac in wastewater
Christine Schirmer1, Juliane Posseckardt1, Mathias Schröder2
1Kurt-Schwabe-Institut Meinsberg, Kurt-Schwabe-Str. 4, 04736 Waldheim, Germany.
Abstract:
Wastewater treatment plants are the main release sources of pharmaceutical compounds present in surface waters. Even at low concentrations, many of these substances have long-term adverse effects on the environment. For an efficient control of pharmaceutical removal, a real-time recognition is a prerequisite. Currently, quantification of such compounds is done in special equipped laboratories and is rather time-consuming and expensive. Here, we introduce a novel biosensor for the detection of the pharmaceutical compound diclofenac, which can be produced with low costs, is easy in handling and can be applied directly on-site. Recognition of diclofenac is based on genetically engineered yeast cells which produce green fluorescent protein in a diclofenac concentration-dependent manner. Centerpiece of the sensor is a foil-based microfluidic flow cell, which allows supply with nutrient solution and analyte while preventing loss of reporter cells. Readout of data is accomplished by a newly developed spectrometric detection unit. With this device, we are able to determine diclofenac concentrations in a range from 10 to 50 μM.
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