Fabrication and Characterization of a Highly-Sensitive Surface-Enhanced Raman Scattering Nanosensor for Detecting Glucose in Urine

Abstract

Herein we utilized coordination interactions to prepare a novel core-shell plasmonic nanosensor for the detection of glucose. Specifically, Au nanoparticles (NPs) were strongly linked with Ag+ ions to form a sacrificial Ag shell by using 4-aminothiophenol (4-PATP) as a mediator, which served as an internal standard to decrease the influence of the surrounding on the detection. The resultant Au-PATP-Ag core-shell systems were characterized by UV-vis spectroscopy, transmission electron microscopy, and surface-enhanced Raman scattering (SERS) techniques. Experiments performed with R6G (rhodamine 6G) and CV (crystal violet) as Raman reporters demonstrated that the Au@Ag nanostructure amplified SERS signals obviously. Subsequently, the Au@Ag NPs were decorated with 4-mercaptophenylboronic acid (4-MPBA) to specifically recognize glucose by esterification, and a detection limit as low as 10−4 M was achieved. Notably, an enhanced linearity for the quantitative detection of glucose (R2 = 0.995) was obtained after the normalization of the spectral peaks using 4-PATP as the internal standard. Finally, the practical applicability of the developed sensing platform was demonstrated by the detection of glucose in urine with acceptable specificity.

Computational Guided Method Applied to LSPR‐Based Biosensor for Specific Detection of the Four‐Serotypes of Dengue Virus in Seropositive Patients

“…Some reasons could explain this factor, but the main one is that the system is not consumer/operator‐friendly with the results largely depending on mathematical calculations to interpret the readouts. [ 42–44 ]…”

Bi-Ligand Modification of Nanoparticles: An Effective Tool for Surface-Enhanced Raman Spectrometry in Salinated Environments

“…It should be stressed, that even though the MPA creates in the presented system the areas with improved accessibility for the analyte, it still mildly shields the analyte from the electromagnetic field around the nanostructures. On the other hand, we believe that the choice of a short-chained ligand can significantly influence the selectivity of analyses [21,22,23]. The blank spectrum of the MPA–PEG–NPs is shown in Figure S5a.…”

Nanosensors based on LSPR are able to serologically differentiate dengue from Zika infections

“…Many nanosensors depend on the use of uncommon electronic/optical devices to perform and cannot operate by using equipments that are immediately available in most diagnostic laboratories. Moreover, many such nanosensors may require specifically trained personnel either to operate the reading devices or to interpret the readouts [63][64][65][66][67] . Although the sensitivity and specificity of many published nanosensors are spectacular, those mentioned constraints might represent significant barriers to the sensors' use, especially in developing and under-developed countries where they are frequently so desperately needed.…”