Implantable devices : the future of blood monitoring ?

Blood analysis is one of the first screening tests used to determine the general status of a person. From such exams it is possible to determine a biochemical analysis of the main metabolites, trace molecular profiles of some organs and evaluate the cellular state of the blood. Among all the important information that can be extracted from the compounds present in the bloodstream, the identification and monitoring of metabolites is a key issue to predict pathological conditions, such as ischemia or stroke, or to keep a chronic disease under control. Indeed, certain metabolites can be upor down-regulated in the blood due to acute or chronic illnesses. A complete list of human metabolites has been collected in the Human Metabolome Database, which counts around 6500 metabolites gathered from books, journal articles and electronic databases [1]. Metabolomics, which is the comprehensive analysis of low-weight compounds, is a powerful tool to predict and understand several pathologies, such as diabetes, obesity, cardiovascular diseases and even cancer, by accurately describing the profile of biological status [2]. Blood tests are typically carried out on a blood sample extracted from the vein of the patient in the clinic and subsequently analyzed in a laboratory. Mass spectroscopy (MS) and nuclear magnetic resonance (NMR) are very powerful techniques that offer the possibility of metabolomic investigation with amazing precision [3]. However, MS and NMR are expensive and barely portable techniques. Moreover, since blood testing is a ‘discrete’ analysis, it is not suitable to follow chronic diseases or potentially dangerous conditions continuously and it cannot be used to adjust a pharmacological treatment. Implantable devices may genuinely represent a valid alternative for continuous monitoring, minimizing the pain and the discomfort of the person. It is always complicated and sometimes dangerous to implant systems that have to be in direct contact with the blood. Thrombosis is the Giovanni De Micheli*, Cristina Boero & Sandro Carrara Editorial