Rapid Detection of in Drinking Water, Based on Filter Immunoassay and Chronoamperometric Measurement.

is a pathogenic bacterium, ubiquitous in freshwater environments and able to colonise man-made water systems from which it can be transmitted to humans during outbreaks. The prevention of such outbreaks requires a fast, low cost, automated and often portable detection system. In this work, we present a combination of sample concentration, immunoassay detection, and measurement by chronoamperometry.

Development of an integrated method of concentration and immunodetection of bacteria.

The microbial quality of water is a key aspect to avoid environmental and public health problems. The low pathogen concentration needed to produce a disease outbreak makes it essential to process large water volumes and use sensitive and specific methods such as immunoassays for its detection. In the present work, we describe the development of a device based on microfiltration membranes to integrate the concentration and the immunodetection of waterborne bacteria.

Miniaturized metal oxide pH sensors for bacteria detection.

It is well known that the metabolic activity of some microorganisms results in changes of pH of the culture medium, a phenomenon that can be used for detection and quantification of bacteria. However, conventional glass electrodes that are commonly used for pH measurements are bulky, fragile and expensive, which hinders their application in miniaturized systems and encouraged to the search for alternatives. In this work, two types of metal oxide pH sensors have been tested to detect the metabolic activity of the bacterium Escherichia coli (E.

Dual chronoamperometric detection of enzymatic biomarkers using magnetic beads and a low-cost flow cell.

In this work we report on the production of a low cost microfluidic device for the multiplexed electrochemical detection of magneto bioassays. As a proof of concept, the device has been used to detect myeloperoxidase (MPO), a cardiovascular biomarker. With this purpose, two bioassays have been optimized in parallel onto magnetic beads (MBs) for the simultaneous detection of MPO endogenous peroxidase activity and quantification of total MPO.

Electrochemical biosensing of non-electroactive targets using ferrocene-labeled magnetic particles and CNT wiring.

We show that target binding onto ferrocene-modified magnetic microparticles (MP-Fc) promotes physical sheltering of the labels. This can be measured electrochemically by CNT wiring, which enhances ten-fold the signals registered compared to direct detection of the MPs alone. As a proof of concept, detection of detergents and antibodies is accomplished.

Chronoamperometric magneto immunosensor for myeloperoxidase detection in human plasma based on a magnetic switch produced by 3D laser sintering.

In this work, an amperometric immunosensor for detection of myeloperoxidase (MPO) in human plasma is reported. Detection is based on the immobilization of anti-MPO antibodies onto magnetic beads (MBs). Following MPO immunocapture and washing steps, MBs are transferred to a customized modular detector device produced by 3D laser sintering.

Electrochemical detection of testosterone by use of three-dimensional disc-ring microelectrode sensing platforms: application to doping monitoring.

Testosterone is one of the androgenic steroid hormones, the consumption of which is considered doping in most sports. Here, we present powerful 3D sensing platforms using novel disc-ring microelectrode array devices and exploit them for the competitive immunosensing of testosterone. Each device contains a microelectrode array that consists of a large number of individual microdiscs and is used as the substrate for immunofunctionalization and assay performance.

Amperometric detection of Enterobacteriaceae in river water by measuring β-galactosidase activity at interdigitated microelectrode arrays.

Two simple methodologies are compared for the detection of faecal contamination in water using amperometry at gold interdigitated microelectrodes. They rely on the detection of β-galactosidase (β-gal) by redox cycling amperometry of the p-aminophenol (PAP) produced by the enzyme from the 4-aminophenyl β-d-galactopyranoside (PAPG) substrate. The use of phages as specific agents for the release of the bacteria-enclosed enzyme allowed the detection of 6×10(5) CFU mL(-1)Escherichia coli in 2 h without any pre-enrichment or preconcentration steps.