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Current rectification with poly-l-lysine-coated quartz nanopipettes.

ABSTRACT: Ion current rectification with quartz nanopipette electrodes was investigated through the control of the surface charge. The presence and absence of a positively charged poly-l-lysine (PLL) coating resulted in the rectified current with opposite polarity. The results agreed with the theories developed for current-rectifying conical nanopores, suggesting the similar underlying mechanism among asymmetric nanostructure in general. This surface condition dependence can be used as the fundamental principle of multi-purpose real-time in vivo biosensors.

SUBMITTER: Umehara S

PROVIDER: S-EPMC2948113 | biostudies-literature | 2006 Nov

REPOSITORIES: biostudies-literature

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Current rectification with poly-l-lysine-coated quartz nanopipettes.

Umehara Senkei S Pourmand Nader N Webb Chris D CD Davis Ronald W RW Yasuda Kenji K Karhanek Miloslav M

Nano letters 20061101 11

Ion current rectification with quartz nanopipette electrodes was investigated through the control of the surface charge. The presence and absence of a positively charged poly-l-lysine (PLL) coating resulted in the rectified current with opposite polarity. The results agreed with the theories developed for current-rectifying conical nanopores, suggesting the similar underlying mechanism among asymmetric nanostructure in general. This surface condition dependence can be used as the fundamental pri ...[more]

PMID: 17090078

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