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PubMed · 16895357

All-optical nanoscale pH meter.

Sandra W Bishnoi·Christopher J Rozell·Carly S Levin·Muhammed K Gheith·Bruce R Johnson·Don H Johnson·Naomi J Halas
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Abstract

We show that an Au nanoshell with a pH-sensitive molecular adsorbate functions as a standalone, all-optical nanoscale pH meter that monitors its local environment through the pH-dependent surface-enhanced Raman scattering (SERS) spectra of the adsorbate molecules. Moreover, we also show how the performance of such a functional nanodevice can be assessed quantitatively. The complex spectral output is reduced to a simple device characteristic by application of a locally linear manifold approximation algorithm. The average accuracy of the nano-"meter" was found to be +/-0.10 pH units across its operating range.

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Equipment DesignEquipment Failure AnalysisHydrogen-Ion ConcentrationNanotechnologyOptics and PhotonicsReproducibility of ResultsSensitivity and SpecificitySpectrum Analysis, RamanSurface PropertiesTransducersEvaluation StudyJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Sandra W Bishnoi, Christopher J Rozell, Carly S Levin, Muhammed K Gheith, Bruce R Johnson, Don H Johnson, Naomi J Halas. 2006. All-optical nanoscale pH meter.. https://doi.org/10.1021/nl060865w

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