Mi Hong

US Patent:

20100039126, Feb 18, 2010

Filed:

May 12, 2009

Appl. No.:

12/464665

Inventors:

Yu Chen - Boston MA, US
Xihua Wang - Allston MA, US
Agniezska Kalinowski - Pittsburgh PA, US
Mi Hong - Quincy MA, US
Pritiraj Mohanty - Los Angeles CA, US
Shyamsunder Erramilli - Quincy MA, US

Assignee:

Trustees of Boston University - Boston MA

International Classification:

G01N 27/04
G01R 27/08

US Classification:

324693, 977957

Abstract:

A sensor system for detecting a chemical or biological species includes a sensing element and a bias and measurement circuit. The sensing element includes nanochannels, each having an outer surface functionalized to chemically interact with the species to create a corresponding surface potential, and each having a sufficiently small cross section to exhibit a shift of a differential conductance characteristic into a negative bias operating region by a shift amount dependent on the surface potential. The bias and measurement circuit applies a bias voltage across two ends of the nanochannels sufficiently negative to achieve a desired dependence of the differential conductance on the surface potential, wherein the dependence has a steeply sloped region of high amplification substantially greater than a reference amplification at a zero-bias condition, thus achieving relatively high signal-to-noise ratio. The bias and measurement circuit converts the measured differential conductance into a signal indicative of presence or activity of the species of interest.

US Patent:

20140030747, Jan 30, 2014

Filed:

Apr 30, 2012

Appl. No.:

13/460116

Inventors:

Yu Chen - Boston MA, US
Xihua Wang - Allston MA, US
Agniezska Kalinowski - Pittsburgh PA, US
Mi Hong - Quincy MA, US
Pritiraj Mohanty - Boston MA, US
Shyamsunder Erramilli - Quincy MA, US

International Classification:

G01N 27/12

US Classification:

435 12, 422 69, 435 14, 4352871, 436501

Abstract:

A sensor system for detecting a chemical or biological species includes a sensing element and a bias and measurement circuit. The sensing element includes nanochannels having an outer surface functionalized for interaction with the species to create a surface potential, and each having a sufficiently small cross section to exhibit a shift of differential conductance into a negative bias operating region by a shift amount dependent on the surface potential. The bias and measurement circuit applies a bias voltage across two ends of the nanochannels sufficiently negative to achieve a desired dependence of the differential conductance on the surface potential. The dependence has a steeply sloped region of high amplification substantially greater than a reference amplification at a zero-bias condition, thus achieving relatively high signal-to-noise ratio. The bias and measurement circuit converts the measured differential conductance into a signal indicative of presence or activity of the species.