Fluidic microsystems for biochemical analysis

Abstract

The realisation of miniaturised analysis systems allowing the detection of specific sequences of the polymer deoxyribonucleic acid (DNA) in a point-of-care format has been a topic of research in recent years. Here, the purpose is to obtain the evidence, whether specific DNA sequences are present or absent in a given biochemical analyte. In a broader sense such an instrument can give information whether a patient has a certain disease or not. In the case of viral or bacterial infections the identification of the disease at an early stage is crucial. The sooner the result is available, the more rapidly the medical scientists can operate against the diseases.<br />The objective of this research is to implement and characterise a cost-efficient, miniaturised analysis system for the fast amplification and detection of DNA and to investigate novel microfluidic devices to study flow behaviour, especially hydrodynamic focusing. Analysis of the flow behaviour of a sample stream inside a microchannel are made, where the sample stream is hydrodynamically squeezed by vertical and horizontal neighbouring sheath flows. The main focus for the miniaturised analysis system is on the realisation of a self-contained and modular designed system, where the DNA amplification is based on the PCR method, and the DNA detection follows an electrochemical-based principle without using any labelling technique. This modular configured analysis system comprises a PCR chip, a DNA sensor (both devices are micromachined) and a compact instrument including a control-measurement unit and a fluidic system to combines both microdevices.