We develop a simple and efficient sensor for biomolecular detection. This sensor employs self assembled beta- amyloid (Aβ) fibril as a template. It is designed to meet the rising demand for early detection of diseases related biomolecules especially micro RNA. Our design offers fast yet accurate detection (down to picomolar) of small DNA in high-throughput manner without the need of sample enrichment. It also brings insight in the develop of novel biomaterial-based sensors in nanoscale.