Electroanalytical sensor based on nanocrystalline diamond electrodes and microelectrode arrays
US9228972B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 2013 |
| Grant date | Jan 5, 2016 |
| Priority date | — |
| Expiry date | Apr 5, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/3278
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A diamond electrode and a diamond microelectrode array for biosensors and electroanalytical applications, such as electrochemical impedance spectroscopy (EIS), are disclosed. The electrode comprises a layer of ultra-smooth conductive nanocrystalline diamond (NCD) having a resistivity of >0.05 Ωcm and a surface roughness of <20 nm Ra. Preferably, the diamond layer comprises boron or nitrogen-doped ultrananocrystalline diamond (UNCD) having an average grain size <10 nm and a surface roughness <10 nm Ra. It may be patterned to define a microelectrode array with a plurality of individually addressable electrodes, each having a diameter in the range from 100 nm to 100 μm. The surface of each microelectrode is hydrogen-terminated before bio-functionalization, i.e. modifying with sensing molecules for detection of a specific biological or chemical target and coating with a blocker for reducing non-specific binding. These diamond electrodes exhibited substantial increases in sensitivity, selectivity and signal reproducibility, e.g. for detection of E. coli K12 using EIS.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.