Development of a new biodetection system independent on known marker molecules by using a novel material for microarrays made from amorphous carbon substrates.

Abstract

A bio-chip substrate made from amorphous carbon has been successfully developed for an innovative and practical biodetection system. The present biochip is a peptide-microarray for protein detection based on a novel principle for use in diagnostics. The properties of the carbon material as substrate carrier offers with regard to its surface chemistry significant advantages over conventional slide-glasses. The biochip detection system described here uses the measurement of fluorescent intensity changes caused by interactions between capture molecules (labelled structured peptides arrayed on substrate) and analytes. Fluorescent intensity changes between with and without analytes are dose-dependent and can be visualized as "protein fingerprints". Recognition in this system, interaction is not dependent on a 1:1 correspondence as with ELISA. Hence this method can be applied even to analytes containing uncharacterized molecules. Statistical data handling, for instance multivariate analyses, allows discrimination of complex analytes such as body fluids. The present biochip used with an in-house developed detection device can be re-used for 10-20 times with the same or different analytes. Capturing molecules in this system are immobilized on the chip-surface through stable amide bonds and this allows washing and even scrub cleaning. This unique material has a potential for dual detection thorough fluorescent intensity changes and mass spectrometric analyses when the chip is used as a sample tray. The latter allows the possibility of discovering marker candidates since this material has high electric conductivity.