Martin A. M. Gijs
Laboratory of Microsystems, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne EPFL, Switzerland Martin.Gijs@epfl.ch
Miniaturization has obvious advantages for diagnostic testing, as it enables reduced reagent consumption, short reaction times and can feature a high degree of parallelization. Microfluidic channel networks are at the basis of a ‘Lab-on-a-Chip (LOC)’, which can be pre-loaded with reagents and, when interfaced with an appropriate master unit, can perform an analytical operation in a highly automatic fashion. The concept permits an individualized and fast diagnostic approach and can be routinely operated by untrained personnel, while maintaining high-quality analysis. We will give a few examples of integrated LOCs, like lateral-flow systems, linear actuated devices and centrifugal devices. Functionalized magnetic micro-and nanoparticles (‘beads’) are increasingly used in LOCs, as they offer a large effective surface and their surface can accommodate a plenum of different chemical functionalities. We will discuss particular ways to manipulate them magnetically and give examples of their use in raw sample pretreatment and washing operations, as well as their use in various immuno-assays and cell-based assays.