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PH-Triggered Molecular Alignment for Reproducible SERS Detection via an AuNP/Nanocellulose Platform.

ABSTRACT: The low affinity of neutral and hydrophobic molecules towards noble metal surfaces hinders their detection by surface-enhanced Raman spectroscopy (SERS). Herein, we present a method to enhance gold nanoparticle (AuNP) surface affinity by lowering the suspension pH below the analyte pKa. We developed an AuNP/bacterial cellulose (BC) nanocomposite platform and applied it to two common pollutants, carbamazepine (CBZ) and atrazine (ATZ) with pKa values of 2.3 and 1.7, respectively. Simple mixing of the analytes with AuNP/BC at pH?

SUBMITTER: Wei H

PROVIDER: S-EPMC4676058 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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pH-Triggered Molecular Alignment for Reproducible SERS Detection via an AuNP/Nanocellulose Platform.

Wei Haoran H Vikesland Peter J PJ

Scientific reports 20151211

The low affinity of neutral and hydrophobic molecules towards noble metal surfaces hinders their detection by surface-enhanced Raman spectroscopy (SERS). Herein, we present a method to enhance gold nanoparticle (AuNP) surface affinity by lowering the suspension pH below the analyte pKa. We developed an AuNP/bacterial cellulose (BC) nanocomposite platform and applied it to two common pollutants, carbamazepine (CBZ) and atrazine (ATZ) with pKa values of 2.3 and 1.7, respectively. Simple mixing of ...[more]

PMID: 26658696

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