Abstract

In recent years we have taken AFM Technology way beyond imaging exploring new frontiers in bio analyses and diagnostics. Micro-fabricated silicon cantilevers arrays offer a novel label-free approach where ligand-receptor binding interactions occurring on the sensor generate nanomechanical signals like bending or a change in mass that is optically detected in-situ. We report the detection of multiple unlabelled biomolecules simultaneously down to picomolar concentrations within minutes. Differential measurements including reference cantilevers on an array of eight sensors enables sequence-specific detection of unlabelled DNA and is suitable to detect specific gene fragments within a complete genome (gene fishing). Expression of detection of inducible genes and the detection of total RNA fragments in a unspecific back ground.will be shown. Ligand-receptor binding interactions, such as antigen recognition will be presented. Antibody activated cantilevers with sFv (single chain fragments) which bind to the indicator proteins show a significant improved sensitivity which is comparable with SPR (Surface Plasmon Resonance). In addition this technology offers a brought variety of receptor molecules application such as e.g. membrane protein recognition, micro-organism detection, enantiomeric separation. New coating procedures, enlargement of the active surface area by dendritic molecules as well as improvement of the receptor-cantilever chemical bond will be presented. This new findings may lead to a novel individual diagnostic assay in a combined label-free GENOMI Cs and PROTEOMIC biomarker sensor (COMBIOSENS) We foresee this novel technology being used as a tool to be applied in the upcoming field of system biology and preventive medicine to evaluate treatment response efficacy for personalized medical diagnostics.