Abstract
In vitro diagnostic platforms of the future, technological possibilities and challengesStig Morten Borch and Liv Furuberg, Microsystems and Nanotechnology, SINTEF ICT, Oslo, Norwaywww.sintef.no/microsystems Point of care in vitro diagnostic (PoC IVD) tests are becoming more and more important tools both for placing early and correct diagnosis and for decentralized monitoring of chronic diseases. PoC IVD platforms as available today do have various limitations linked to reliability, accuracy, sensitivity, robustness, compactness, speed, the panel of parameters available, cost or ease of use. The use of new concepts of controlled microfluidics combined with advanced chemistries, detection principles and compact instrumentation do open new possibilities in improving all these features considerably. Lab-on-a-chip formats include closed disposable microfluidic devices holding all reagents and elements necessary for analyzing a sample for one or multiple parameters at the time. These small devices may within a few minutes be automatically operated by compact instruments allowing processing of both the sample and subsequent advanced quantitative bioanalytical assays. Microfluidics implies that very small volumes of both samples and reagents may be used, but still allowing high analytical accuracy and reliability. Typically, in SINTEF’s Lab-on-a-chip prototype platform, a defined volume (0.4 to 1 µL) of plasma is isolated from 10 µL (finger prick) of whole blood within 30 seconds and then the exactly metered plasma fractions are allowed to be further processed in advanced assays, all within the same chip. The reagents need to be stored as stable formulations (liquid and / or dry) at defined locations within the chip. This requires unique knowledge as to reagent formulation, device design and materials used. In order to design very fast immunometric assays the analytes should be forced to interact with an excess of capturing antibodies immobilized on defined surfaces. Furth