Glucose Sensing Using Near-Infrared Surface-Enhanced Raman Spectroscopy: Gold Surfaces, 10-Day Stability, and Improved Accuracy
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- 作者：Douglas A. Stuart ; Chanda Ranjit Yonzon ; Xiaoyu Zhang ; Olga Lyandres ; Nilam C. Shah ; Matthew R. Glucksberg ; Joseph T. Walsh ; and Richard P. Van Duyne
- 刊名：Analytical Chemistry
- 出版年：2005
- 出版时间：July 1, 2005
- 年：2005
- 卷：77
- 期：13
- 页码：4013 - 4019
- 全文大小：328K
- 年卷期：v.77,no.13(July 1, 2005)
- ISSN：1520-6882
文摘
This research presents the achievement of significantmilestones toward the development of a minimally invasive, continuously monitoring, glucose-sensing platformbased on the optical quantitation of glucose in interstitialfluid. We expand our initial successes in the measurementof glucose by surface-enhanced Raman scattering (SERS),demonstrating substantial improvements not only in thequality and optical properties of the substrate system itselfbut also in the robustness of the measurement methodology and the amenability of the technique to compact,diode laser-based instrumentation. Herein, we comparethe long-term stability of gold to silver film over nanosphere (AuFON, AgFON) substrates functionalized witha partitioning self-assembled monolayer (SAM) using bothelectrochemical and SERS measurements. AuFONs werefound to be stable for a period of at least 11 days. Theswitch to AuFONs not only provides a more stable surfacefor SAM formation but also yields better chemometricresults, with improved calibration and validation over arange of 0.5-44 mM (10-800 mg/dL). Measured valuesfor glucose concentrations in phosphate-buffered saline(pH ~7.4) based on 160 independent SERS measurements on AuFONs have a root-mean-square error ofprediction of 2.7 mM (49.5 mg/dL), with 91% of thevalues falling within an extended A-B range on anexpanded Clarke error grid. Furthermore, AuFONs exhibit surface plasmon resonances at longer wavelengthsthan similar AgFONs, which make them more efficient forSERS at near-infrared wavelengths, enabling the use oflow-power diode lasers in future devices.