A portable micromodule for gluten extraction
Coeliac disease is an autoimmune condition which is triggered by gluten, a composite of the proteins, glutenin and gliadin. The effects of this intolerance are mainly related to damage of the bowel. Malabsorption is one of the main effects of the condition. This can lead to vitamin and mineral deficiencies, fatigue, and weight loss with failure to develop properly in young children. A restricted diet that does not incorporate gluten is crucial for sufferers. This provided the impetus for the European project CD-CHEF to develop a disposable microsystem for the detection of toxic gluten sequences. Appropriately, the CHEF in the project acronym is derived from 'chip with integrated extraction and fluidics' which aptly describes the elements of the microsystem. Project partners at the Institute of Microtechnology Mainz GmbH in Germany developed a micromodule specifically for the extraction of gluten from all types of foodstuffs. The extraction method can be viewed as three separate modules incorporating a chip, an extraction module and a centrifuge. The chip provides buffer storage for the extract as well as an interface for the propulsion system. The components for actuation consist of a syringe pump which operates on the basis of peristalsis and a valve which enables sufficient pressure to be applied to the three modules. The extraction module is essentially a silicon tube for the sample and the buffer which is pre-filled using the valve. The sample and the buffer are mixed together vigorously. Below the tube is a heating coil to achieve the required 90°C for extraction of the processed food. The micromodule contains a number of disposable elements to prevent contamination between food samples. These include the polymer block where the valve is housed, the silicon tube and its connectors to the chip. For cost-effectiveness, all other components are re-usable as they do not come into contact with the sample being processed. The prototype demonstration model can be merged with biosensor equipment with no loss of portability. There has been wide interest in the product, from consumers to biotechnical companies.