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Noise and bandwidth performance of single-molecule biosensors

Technological advances in fluorescent probes, solid-state imagers, and microscopy techniques have enabled biomolecular studies at the single-molecule level. Fluorescent techniques are highly specific but their bandwidth is fundamentally limited by the number of photons that can be collected. New electronic sensors including nanopores and nanotube field-effect transistors offer different tradeoffs between bandwidth and noise levels. Here, we discuss the performance of these direct solid-state interfaces and their potential for sensing single-molecule dynamics at shorter timescales.
Date of Conference: 19-21 Sept. 2011
Date Added to IEEE Xplore: 20 October 2011
ISBN Information:
ISSN Information:
INSPEC Accession Number: 12316546
Publisher: IEEE

I. Introduction

Biomolecular systems are traditionally studied using fluorescence-based ensemble measurements of the average characteristics of a relatively large number of molecules. Among the most common in vitro applications are DNA microarrays to identify gene expression profiles [1] and enzyme-linked immunosorbent assays (ELISA) to identify proteins [2]. While much can be determined with ensemble measurements, scientific and technological interest is rapidly moving to single-molecule techniques. When probing biomolecules at the single-molecule level, dynamics can be observed which are usually hidden in ensemble measurements. The most popular single-molecule techniques are also based on fluorescence [3]. Though fluorescent probes are highly specific, they use light as an intermediary between the biological system and measurement electronics, which results in fundamental constraints in resolution and bandwidth due to the countable number of photons emitted. Single-molecule measurements of the kinetics of fast biomolecular processes are often unavailable through fluorescent techniques, as they lack the necessary temporal resolution.


Bioelectronic Systems Laboratory, Columbia University, New York, USA
Bioelectronic Systems Laboratory, Columbia University, New York, USA
Bioelectronic Systems Laboratory, Columbia University, New York, USA