Method and apparatus for enhanced detection of toxic agents

• US 20080032326A1
• Filed: 11/10/2005
• Published: 02/07/2008
• Est. Priority Date: 08/31/2005
• Status: Active Grant

• Current Assignee: University of Tennessee Research Foundation (University of Tennessee), UT-Battelle LLC
• Original Assignee: University of Tennessee Research Foundation (University of Tennessee)
• Inventors: Rodriguez, Miguel, Wu, Jie Jayne, Qi, Hairong, Greenbaum, Elias
• Granted Patent: US 8,198,075 B2
• Time in Patent Office: Days
• US Class Current: 435/34
• CPC Class Codes: C12Q 1/025 for testing or evaluating the effect of chemical or biological compounds, e.g. drugs, cosmetics antimicrobial activity C12Q1/18

Abstract

A water quality analyzer for real-time detection according to the invention comprises a biased AC electro-osmosis (ACEO) cell for receiving a fluid to be analyzed having a plurality photosynthetic organisms therein, and concentrating the plurality photosynthetic organisms into at least one concentrated region. A photodetector is provided for obtaining a measured photosynthetic activity of the plurality of photosynthetic organisms in the concentrated region; wherein chemical, biological or radiological agents reduce a nominal photosynthetic activity of the photosynthetic organisms. An electronics package analyzes the measured photosynthetic activity to indicate a presence of the chemical, biological or radiological agents in the fluid.

Claims

14. A water quality analyzer, comprising:

a biased AC electro-osmosis (ACEO) cell for receiving a fluid to be analyzed having a plurality photosynthetic organisms therein and concentrating said plurality photosynthetic organisms into at least one concentrated region, and

a photodetector for obtaining a measured photosynthetic activity of said plurality of photosynthetic organisms in said concentrated region, wherein chemical, biological or radiological agents reduce a nominal photosynthetic activity of said photosynthetic organisms, and

an electronics package for analyzing measured photosynthetic activity to indicate a presence of said chemical, biological or radiological agents in said fluid.

1. A method of biosensor-based detection of toxins, comprising the steps of:

providing a water quality analyzer of claim 14,

concentrating a plurality photosynthetic organisms in a fluid to be analyzed into a concentrated region using biased AC electro-osmosis;

obtaining a measured photosynthetic activity of said photosynthetic organisms in said concentrated region, wherein chemical, biological or radiological agents reduce a nominal photosynthetic activity of said photosynthetic organisms, and

determining a presence of at least one of said chemical, biological or radiological agents, or precursors thereof, in said fluid based on said measured photosynthetic activity.

2. The method of claim 1, wherein said plurality of photosynthetic organisms are naturally-occurring, free-living, indigenous organisms in said fluid.

3. The method of claim 1, wherein said photosynthetic activity comprises chlorophyll fluorescence induction.

4. The method of claim 1, wherein a lab-on-a-chip system is used for said concentrating step.

5. The method of claim 1, wherein said fluid is drawn from a source of primary-source drinking water.

6. The method of claim 5, further comprising the step of refreshing a supply of said photosynthetic organisms by drawing a fresh supply of said drinking water and repeating said method.

7. The method of claim 1, wherein said determining step further comprises the steps of:

providing at least one time-dependent control signal generated by said photosynthetic organism is said fluid;

obtaining a time-dependent biosensor signal from said biosensor in said fluid for the presence of one or more of said agents;

processing said time-dependent biosensor signal to obtain a plurality of feature vectors using at least one of amplitude statistics and a time-frequency analysis, and

determining said presence of at least one of said chemical, biological or radiological agents, or precursors thereof, from said feature vectors based on reference to said control signal.

8. The method of claim 7, wherein said time-frequency analysis comprises wavelet coefficient analysis.

9. The method of claim 7, wherein both said amplitude statistics and time-frequency analysis are used in said processing step.

10. The method of claim 7, further comprising the step of identifying which of said agents are present in said fluid.

11. The method of claim 10, wherein a linear discriminant method is used for said identifying step.

12. The method of claim 11, wherein said linear discriminant method comprises support vector machine (SVM) classification.

13. The method of claim 1, wherein a DC bias for said biased ACEO is from 1 to 10 volts.

15. The sensor of claim 14, wherein said ACEO cell comprises a lab-on-a-chip device.

16. The sensor of claim 15, wherein said lab-on-a-chip device includes at least one electronic device on said chip.

17. The sensor of claim 14, further comprising structure for communicating said measured photosynthetic activity or said measured photosynthetic activity after analysis by said electronics package to one or more remote sites. _