Nanoporous Bioelectrochemical Sensors for Measuring Redox Potential in Biological Samples

Patent metadata

Field	Value
Publication number	US-2016266090-A1
Application number	US-201415030958-A
Country	US
Kind code	A1
Filing date	Oct 21, 2014
Priority date	Oct 21, 2013
Publication date	Sep 15, 2016
Grant date	—

Abstract

A bioelectrochemical sensor utilizing a nanoporous gold electrode. The bioelectrochemical sensor is suitable for measuring redox in biologic media while having increased resistance to biofouling as compared to conventional electrodes such as planar gold electrodes, due to greater exposed surface area of the three-dimentional ligature structure defining the nanopores. The nanopores have a pore size of 5-100 nm, preferably with an average pore size of less than 50 nm, and more preferably with an average pore size of less than 20 nm.

First claim

What is claimed is:

1 . A bioelectrochemical sensor, comprising:
a first electrode including a nanoporous precious metal; and a reference electrode.

2 . The bioelectrochemical sensor of claim 1 , the nanoporous precious metal of the first electrode being nanoporous gold.

3 . The bioelectrochemical sensor of claim 1 , the pores of the nanoporous precious metal of the first electrode having a pore size of 100 nm or less.

4 . The bioelectrochemical sensor of claim 3 , the nanoporous precious metal of the first electrode having an average pore size of less than 50 nm.

5 . The bioelectrochemical sensor of claim 3 , the nanoporous precious metal of the first electrode having an average pore size of less than 20 nm.

6 . The bioelectrochemical sensor of claim 1 , further comprising a counter electrode.

7 . The bioelectrochemical sensor of claim 1 , the reference electrode being a silver/silver chloride electrode.

8 . The bioelectrochemical sensor of claim 6 , the counter electrode being platinum.

9 . The bioelectrochemical sensor of claim 1 , in combination with a block having a microfluidic channel therein, the microfluidic channel including a portion aligned with an exposed nanoporous region of the first electrode.

10 . A method for manufacturing a bioelectrochemical sensor comprising:
providing a gold leaf; etching the gold leaf in an etching solution to impart a nanoporous region to the gold leaf; forming a nanoporous gold electrode from the etched gold leaf; and providing a reference electrode with the nanoporous gold electrode.

11 . (canceled).

12 . The method of claim 10 , and in providing the reference electrode, the reference electrode is a silver/silver chloride electrode.

13 . The method of claim 10 , further comprising providing a counter electrode on a side of the nanoporous gold electrode opposite from the reference electrode.

14 . The method of claim 13 , and in providing the reference electrode, the reference electrode is platinum.

15 . The method of claim 10 , further comprising providing a block having a microfluidic channel therein, the microfluidic channel including a portion aligned with an exposed nanoporous region of the first electrode.

16 . A method for manufacturing a bioelectrochemical sensor comprising:
forming a nanoporous gold electrode by (a) co-sputtering gold onto a substrate; and (b) etching away materials deposited onto the substrate other than the gold, whereby a nanoporous gold surface remains; and providing a reference electrode with the nanoporous gold electrode.

17 . The method of claim 16 , and in providing the reference electrode, the reference electrode is a silver/silver chloride electrode.

18 . The method of claim 16 , further comprising providing a counter electrode on a side of the nanoporous gold electrode opposite from the reference electrode.

19 . The method of claim 18 , and in providing the reference electrode, the reference electrode is platinum.

20 . The method of claim 16 , further comprising providing a block having a microfluidic channel therein, the microfluidic channel including a portion aligned with an exposed nanoporous region of the first electrode.

21 . A method of measuring redox potential in a biological sample from a source comprising contacting the sample with a bioelectrochemical sensor of claim 1 under conditions sufficient to obtain the redox potential of the biological sample.

22 . The method of claim 21 , wherein the biological sample comprises blood, serum, urine, exhaled breath condensate, or tissue interstitium.

23 . The method of claim 21 , wherein the source of the biological sample is a subject suffering from metabolic or oxidative stress.

24 . The method of claim 21 , wherein the source of the biological sample is a subject suffering from multiple organ dysfunction syndrome (MODS), inflammation, ischemia/reperfusion injury, lung vascular injury, sepsis, trauma, cardiac arrest, burns, or shock.

25 . The method of claim 21 , wherein the source of the biological sample is a subject suffering from cardiogenic shock, neurogenic shock, distributive shock, septic shock, traumatic shock, hemorrhagic shock, burn shock, or hypovolemic shock.

26 . The method of claim 21 , wherein the source of the biological sample is a harvested organ or blood product.

27 . The method of claim 21 , further comprising measuring the redox potential of a second biological sample from the source to obtain a second redox potential, wherein the second redox potential indicates the sample's oxidative state over time.

28 . The method of claim 21 , and in contacting the sample with the bioelectrochemical sensor, the bioelectrochemical sensor is in combination with the block of claim 9 , and contacting the sample includes placing the sample in a flow path including the microfluidic channel of the block, whereby the sample is placed in fluid communication with the bioelectrochemical sensor.

Assignees

• Univ Michigan Regents

Inventors

• Daniels Rodney C
• Ward Kevin R
• Collinson Maryanne M

Classifications

• G01N27/3272

  Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels (optical biosensors G01N33/52) · CPC title

• B01L2300/0896

  Nanoscaled · CPC title

• G01N33/48707

  by electrical means (G01N33/49, G01N33/493 take precedence) · CPC title

• B01L2300/12

  Specific details about materials · CPC title

• G01N27/3277

  being a redox reaction, e.g. detection by cyclic voltammetry (voltammetry per se G01N27/42, G01N27/48) · CPC title