Biosensors and Carbon Nanotubes. Lakshmi Jagannathan. Enzyme-Coated Carbon Nanotubes as Single-Molecule Bionsensors 1. Introduction and Motivation Physical Immobilization of Protein Method/Experimentation Result/Evidence of Immobilization (AFM) Electrical Characteristics
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(van der Waals coupling)
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Without Gox Immobilization, cannnot tell difference between different pH
After Gox, conductance increases for higher pH
Gate voltage changes by 20mV- conductance changes
Sensitivity due to charged groups on Gox that become more negative with increasing pHElectrical Characteristics- Results
Figure 3. The pH was set by using 0.1 mM HCl in milli-Q water (pH 4) and 0.1 mM KCl in milli-Q water (pH 5.5). For all measurements the source-drain voltage was kept at 9.1 mV. It is seen that the conductance increases with increasing pH and that pH changes induce a reversible change in the conductance.