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  • Node-pore sensing: a robust, high-dynamic range method for detecting biological species.

Node-pore sensing: a robust, high-dynamic range method for detecting biological species.

Lab on a chip (2013-02-07)
Karthik R Balakrishnan, George Anwar, Matthew R Chapman, Trongtuong Nguyen, Anand Kesavaraju, Lydia L Sohn
ABSTRACT

Resistive-pulse sensing (RPS), which is based on measuring the current pulse produced when a single particle transits a pore or channel, is an extremely versatile technique used to determine the size and concentration of cells and viruses and to detect single molecules. A major challenge to RPS is dynamic range: smaller particles in a heterogeneous sample can go undetected because of low signal-to-noise ratios (SNRs) and the fact that the pore size must be commensurate with that of the largest particles. Here, we describe a fundamentally different pore that provides an unprecedented dynamic detection range, from tens of nanometers to several microns in size, without the need for pre-sorting or filtration. Because of its unique geometry--nodes inserted along the channel--our pore produces distinct electronic signatures that overcome low SNRs. We demonstrate the power of our device by directly detecting and enumerating human immunodeficiency virus (HIV) in human plasma.

MATERIALS
Product Number
Brand
Product Description

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