Catheter-based sensors for the intestinal detection of molecular biomarkers in the context of functional bowel disorders

Food-induced abdominal symptoms are extremely common and remain poorly understood. In a recent Belgian survey, 18% of the adults reported symptoms of the irritable bowel syndrome (IBS), and half of them identified certain foods as triggers of their symptoms. Histamine and serotonin are two important signaling molecules in the gastrointestinal mucosa, thought to be involved in adverse reactions to food. However, it has been notoriously difficult to measure the release of these substances and to identify relevant triggering foods and pathways for therapy. To study the release of both biomarkers in the small intestines of patients, we will develop a nasogastric catheter that is able to detect both types of molecules selectively, quantitatively, and in real time. This way, it will become possible to correlate dietary or other stimuli with the time-dependent molecular concentrations. Regarding receptors, we will use molecularly imprinted polymers (MIPs) that are adapted to the conditions in bowel fluid. To determine the absolute concentrations, we will use the MIPs as coatings on electrodes that alter their electronic properties upon binding of histamine and serotonin. This catheter sensor offers the potential to vastly expand our knowledge on the role of these signals in response to food and on the pathogenesis of the symptoms. At longer term, this holds the promise of better diagnosis and treatment options for patients suffering of food-related,debilitating symptoms.