Real-time detection of water contaminants
Provided herein is a field-effect transistor based sensor for real-time detection of water contaminants and methods of use thereof.
1. A field-effect transistor sensor for detecting a target in an aqueous environment comprising:
a reduced graphene oxide layer coated with a passivation layer;
one or more gold nanoparticles in contact with the passivation layer; and
at least one probe bound to the one or more nanoparticles;
wherein the nanoparticles are discrete nanoparticles, and wherein the passivation layer is about 1 to about 4 nanometers thick.
2. The sensor of claim 1 , wherein the passivation layer is aluminum oxide.
3. The sensor of claim 1 , wherein the passivation layer is about 1 to about 3 nanometers thick.
4. The sensor of claim 3 , wherein the passivation layer is about 3nanometers thick.
5. The sensor of claim 1 , wherein the gold nanoparticles are distributed uniformly on the reduced graphene oxide layer.
6. The sensor of claim 1 , wherein the gold nanoparticles are about 3 to about 5 nanometers in size.
7. The sensor of claim 1 , wherein the gold nanoparticles are at least 5 nanometers apart.
8. The sensor claim 1 , wherein more than one probe is bound to the one or more nanoparticles.
9. The sensor of claim 8 , wherein the more than one probes are different.
10. The sensor of claim 1 , wherein a target is a contaminant.
11. The sensor of claim 1 , wherein a target is a water additive.
12. The sensor of claim 1 , wherein the at least one probe detects a target selected from anions, cations, metals, viruses, bacteria, organic contaminants or a combination thereof.
13. The sensor of claim 12 , wherein the bacteria are Giardia sp., Ligonella sp., or Escheria coli.
14. The sensor of claim 1 , wherein the sensor is connected to a display.
15. The sensor of claim 1 , wherein the at least one probe detects a target that is a metal.
16. The sensor of claim 15 , wherein the metal is selected from lead, arsenic, cadmium, copper, iron, or mercury, or a combination thereof.
17. The sensor of claim 15 , wherein the probe comprises thioglycolic acid (TGA) or an aptamer.
18. The sensor of claim 1 , wherein the passivation layer is about 2 to about 4nanometers thick.
19. A method for detecting a target in an aqueous sample comprising:
a. contacting an aqueous sample with a sensor according to claim 1 ;
b. applying a current to the sensor; and
c. detecting a change in an electrical characteristic.
20. The method of claim 19 , wherein the electrical characteristic is resistance.
21. The method of claim 19 , wherein more than one target is detected in the sample using a single sensor with more than one probe.
22. The method of claim 19 , wherein the aqueous sample is from one selected from a group of a water distribution system and a wastewater treatment process.
23. The method of claim 19 , wherein the change in resistance is detected continuously.
24. The method of claim 19 , wherein the change in resistance is detected periodically by the sensor.
25. The method of claim 19 , further comprising transmitting the change in resistance to a display.