Photoelectric chemical sensor and sensing method utilizing interfacial photo-voltages

• US 8,354,647 B2
• Filed: 04/07/2008
• Issued: 01/15/2013
• Est. Priority Date: 11/08/2000
• Status: Active Grant

• Current Assignee: University of North Florida (State University System of Florida)
• Original Assignee: University of North Florida (State University System of Florida)
• Inventors: Huebner, Jay S., Arrieta, Rodolfo T.
• Primary Examiner(s): Nagpaul, Jyoti
• Application Number:
  US12/080,880
• Publication Number:
  US 20080277590A1
• Time in Patent Office: 1,744 Days
• Field of Search: 422/50, 422/82.02, 422/82.09, 422/500, 250/393, 250/338.3, 436/147, 436/161
• US Class Current: 250/393
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G01N 27/305 optically transparent or photoresponsive electrodes

Abstract

A device and method which comprises a sensing surface on a membrane, solid surface or electrode, where the sensing surface contains a photo-voltage active material chosen in relation to a particular target substance to be detected and quantified. The photo-voltage active material is of a type which produces an interfacial photo-voltage electrical signal upon illumination. The particular photo-voltage active material chosen for a particular target substance is one in which the presence of the target substance causes a change in the electrical signal produced. The presence of the target substance modifies the expected photo-voltage produced by the sensing surface upon illumination. The photo-voltage produces signals which are detected by electronic circuits, and the presence and concentration of the target substance is determined by analyzing the difference between the photo-voltage of the target sample versus the photo-voltage of a control sample lacking the target substance.

Claims

1. An apparatus for detecting the presence and concentration of a target substance in a solution through comparison of the differences in interfacial photo-voltages between a control solution and a target solution containing the target substance, wherein a photo-voltage active material is utilized which produces interfacial photo-voltage upon illumination and which produces a different amount of interracial photo-voltage upon illumination when in contact with said target substance, the apparatus comprising:

a light source for illumination;

a photo-voltage active material which produces interfacial photo-voltage upon illumination and which produces a different amount of interfacial photo-voltage upon illumination when in contact with said target substance, said photo-voltage active material being adsorbed onto the surface of an electrode positioned such that said photo-voltage active material is in contact with said target solution and such that said interfacial photo-voltage produced by said photo-active material upon illumination is transferred to said electrode;

a digital signal processor in electrical communication with said electrode to detect said photo-voltages and to generate a signal for analysis;

means to analyze said signal to determine the presence and concentration of said target substance.

2. The apparatus of claim 1, further comprising a container to receive a target solution containing a target substance, and wherein said electrode is disposed within said container.

3. The apparatus of claim 2, further comprising additional electrodes disposed within said container, each said electrode having a photo-voltage active material adsorbed thereon which produces interfacial photo-voltage upon illumination and which produces a different amount of interfacial photo-voltage upon illumination when in contact with said target substance, said photo-voltage active material being in contact with said target solution.

4. The apparatus of claim 3, wherein each of said adsorbed photo-voltage active materials on said electrode and said additional electrodes is a different photo-voltage active material.

5. The apparatus of claim 1, wherein said light source is chosen from the group of light sources consisting of lasers, stroboscopes and LEDs.

6. The apparatus of claim 1, wherein said electrode comprises a self-assembled monolayer.

7. The apparatus of claim 1, where said analyzer means is an oscilloscope.