Glucose Detection of 4-Mercaptophenylboronic Acid-Immobilized Gold-Silver Core-Shell Assembled Silica Nanostructure by Surface Enhanced Raman Scattering

Abstract

The importance of glucose in many biological processes continues to garner increasing research interest in the design and development of efficient biotechnology for the sensitive and selective monitoring of glucose. Here we report on a surface-enhanced Raman scattering (SERS) detection of 4-mercaptophenyl boronic acid (4-MPBA)-immobilized gold-silver core-shell assembled silica nanostructure (SiO2@Au@Ag@4-MPBA) for quantitative, selective detection of glucose in physiologically relevant concentration. This work confirmed that 4-MPBA converted to 4-mercaptophenol (4-MPhOH) in the presence of H2O2. In addition, a calibration curve for H2O2 detection of 0.3 µg/mL was successfully detected in the range of 1.0 to 1000 µg/mL. Moreover, the SiO2@Au@Ag@4-MPBA for glucose detection was developed in the presence of glucose oxidase (GOx) at the optimized condition of 100 µg/mL GOx with 1-h incubation time using 20 µg/mL SiO2@Au@Ag@4-MPBA and measuring Raman signal at 67 µg/mL SiO2@Au@Ag. At the optimized condition, the calibration curve in the range of 0.5 to 8.0 mM was successfully developed with an LOD of 0.15 mM. Based on those strategies, the SERS detection of glucose can be achieved in the physiologically relevant concentration range and opened a great promise to develop a SERS-based biosensor for a variety of biomedicine applications.

Advancing Glycan Analysis: A New Platform Integrating SERS, Boronic Acids, and Machine Learning Algorithms

“…The thiol-silver bonding enhances the adsorption of 4MBA on silver nanoparticles, resulting in higher signal intensities. [37] Higher SERS signals of 4MBA-glucose nanopapers lead to a higher signal-to-noise ratio (S/N ≈ 417), compared to the spectra on 1TBA-glucose nanopapers (S/N ≈ 148).…”

Nonenzymatic Hydrogen Peroxide Detection Using Surface-Enhanced Raman Scattering of Gold–Silver Core–Shell-Assembled Silica Nanostructures

“…SiO 2 @Au@Ag alloy NPs were prepared using a protocol reported by Pham et al [27,[34][35][36][37][38][39]. The transmission electron microscopy (TEM, JEOL, Akishima, Tokyo) images and UV-vis extinction spectra (Mecasys, Seoul, Korea) of the SiO 2 @Au@Ag alloy NPs are shown in Figure S1.…”

“…The SERS enhancement of the SiO 2 @Au@Ag alloy NPs is due to the enhancement of the cavity plasmon resonance and the variation of the refractive index of nanomaterials, by lead shifting the operation wavelength and enhancing the local electromagnetic fields of the hotspot region [29,30,33]. Because of their reliability and strength, SiO 2 @Au@Ag alloy-based substrates were developed for diagnosing cancers and detecting pesticides, thiram, and glucose [27,[34][35][36][37][38][39]. However, their use in nanozymes and the detection of H 2 O 2 using SERS requires further investigation.…”

Advancing Glycan Analysis: A New Platform Integrating SERS, Boronic Acids, and Machine Learning Algorithms

“…SERS intensities from 4MBA functionalized nanopapers were stronger than the signals from 1TBA functionalized nanopapers. The thiol-silver bonding enhances the adsorption of 4MBA on silver nanoparticles, resulting in higher signal intensities 40 . Higher SERS signals of glucose-4MBA nanopapers lead to a higher signal-to-noise ratio (S/N ≈ 417), compared to the spectra on glucose-1TBA nanopapers (S/N ≈ 148).…”