On-chip microfluidic systems for determination of L-glutamate based on enzymatic recycling of substrate.

Two microfluidic systems have been developed for specific analysis of L-glutamate in food based on substrate recycling fluorescence detection. L-glutamate dehydrogenase and a novel enzyme, D-phenylglycine aminotransferase, were covalently immobilized on (i) the surface of silicon microchips containing 32 porous flow channels of 235 mum depth and 25 mum width and (ii) polystyrene Poros beads with a particle size of 20 mum. The immobilized enzymes recycle L-glutamate by oxidation to 2-oxoglutarate followed by the transfer of an amino group from D-4-hydroxyphenylglycine to 2-oxoglutarate.

Express detection of nonylphenol in water samples by fluorescence polarization immunoassay.

The development of express method for detection of endocrine-disrupting chemicals (EDC) such as alkylphenols is required for ecological monitoring. Several attempts have been made to produce antibodies against 4-nonylphenol (NP) in recent years. This work describes the production of new antibodies against NP and also summarizes the characterization of antibodies obtained earlier.

Microfluidic enzyme immunosensors with immobilised protein A and G using chemiluminescence detection.

Affinity proteins were covalently immobilised on silicon microchips with overall dimensions of 13.1 x 3.2 mm, comprising 42 porous flow channels of 235 microm depth and 25 microm width, and used to develop microfluidic immunosensors based on horseradish peroxidase (HRP), catalysing the chemiluminescent oxidation of luminol/p-iodophenol (PIP).

Microfluidic enzyme immunoassay using silicon microchip with immobilized antibodies and chemiluminescence detection.

Silicon microchips with immobilized antibodies were used to develop microfluidic enzyme immunoassays using chemiluminescence detection and horseradish peroxidase (HRP) as the enzyme label. Polyclonal anti-atrazine antibodies were coupled to the silicon microchip surface with an overall dimension of 13.1 x 3.

Antibody-based methods for surfactant screening.

This brief overview summarises the immunoassay-based results obtained in the course of two years of the European INCO-Copernicus project BIOTOOLS. The project is aimed at simplifying the procedures for detection of surface active compounds (SAC) using, among others, antibody-based methods, i.e.