Surface-enhanced Raman scattering (SERS) represents a compelling detection methodology centered on the electromagnetic fields, commonly termed "hot spots", generated around noble nanoparticles. Nonetheless, the efficacy of electromagnetic field (EMF) amplification is constrained when utilizing individual nanoparticles. There has been a notable lack of experimental and theoretically simulated studies regarding the increase of the electromagnetic field when gold nanorods with different aspect ratios undergo self-assembly in either perpendicular or parallel orientations to substrates. This research presents a novel and facile methodology for fabricating SERS nanosubstrates. This method entails self-assembling gold nanorods (AuNRs) with short and medium aspect ratios (ARs) through natural evaporation. By manipulating the water-to-ethanol ratios, we ascertain the appropriate conditions for the rational alignment of the nanorods in both perpendicular and parallel orientations relative to the silicon substrate. These nanosubstrates have been experimentally evaluated for their ability to improve the Surface-Enhanced Raman Scattering (SERS) performance, presenting a novel perspective in this field. In addition, a computational analysis employing the finite-difference time-domain (FDTD) method was conducted to elucidate the electromagnetic field generated by nanoarrays when subjected to incident light of varying wavelengths, including 532 nm, 638 nm, and 785 nm. Notably, the FDTD simulation outcomes indicated that gold nanorods (AuNRs) possessing an aspect ratio of 3.0 and nanogaps of 2.0 nm exhibited exceptional electromagnetic field characteristics when aligned parallel to the substrate under 532 nm laser illumination. Conversely, when the AuNRs were oriented perpendicular to the substrates, they produced lower EMFs upon interaction with excitation laser light. These findings can potentially contribute to the advancement of SERS nanosubstrate design.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/d4dt03259d | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A wearable antifouling electrochemical sensor integrated with an antimicrobial microneedle array for uric acid detection in interstitial fluid.
Anal Chim Acta
February 2025
Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science & Technology, Qingdao, 266042, China. Electronic address:
Wearable microneedle array (MNA) based electrochemical sensors have gained increasing attention for their capability to analyze biomarkers in the interstitial fluid (ISF), enabling noninvasive, continuous monitoring of health parameters. However, challenges such as nonspecific adsorption of biomolecules on the sensor surfaces and the risk of infection at the microneedle penetration sites hinder their practical application. Herein, a wearable dual-layer microneedle patch was prepared to overcome these issues by integrating an antimicrobial microneedle layer with an antifouling sensing layer.
View Article and Find Full Text PDFUltrabright contrast agents with synergistic Raman enhancements for precise intraoperative imaging and photothermal ablation of orthotopic tumor models.
J Nanobiotechnology
January 2025
State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai, 200438, China.
Background: Intraoperative imaging is critical for achieving precise cancer resection. Among available techniques, Raman spectral imaging emerges as a promising modality due to its high spatial resolution and signal stability. However, its clinical application for in vivo imaging is limited by the inherently weak Raman scattering signal.
View Article and Find Full Text PDFDevelopment of a smartphone-assisted multiple colorimetric detection assay for GSH in food based on the degradation of gold nanorods.
Anal Sci
January 2025
School of Life Sciences, Shanghai University, 381 Nanchen Rd, Shanghai, 200444, China.
Glutathione (GSH) is a tripeptide and natural reducing agent composed of glutamic acid, glycine, and cysteine. Its level in the human body is closely linked to human health, such as diabetes, Alzheimer's disease, and cancer. The supplementation of exogenous GSH could bring health benefits and GSH detection in food is of considerable importance.
View Article and Find Full Text PDFFabrication of TeNT/TeO heterojunction based sensor for ultrasensitive detection of NO.
J Hazard Mater
January 2025
School of Integrated Circuits, Dalian University of Technology, Dalian, Liaoning 116024, China. Electronic address:
Tellurium nanotubes (TeNT) heterojunction with Tellurium oxide (TeO) were prepared by in situ oxidation at elevated temperatures in air. The chemiresistive type NO sensor was then fabricated by depositing the synthesized TeNT/TeO on the integrated gold electrodes. The response of the TeNT/TeO based sensor to 600 ppb NO was 38.
View Article and Find Full Text PDFBacterial Wastewater-Based Epidemiology Using Surface-Enhanced Raman Spectroscopy and Machine Learning.
Nano Lett
January 2025
Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
Although wastewater-based epidemiology has been used extensively for the surveillance of viral diseases, it has not been used to a similar extent for bacterial diseases. This is in part owing to difficulties in distinguishing pathogenic from nonpathogenic bacteria using PCR methods. Here, we show that surface-enhanced Raman spectroscopy (SERS) can be a scalable, label-free method for the detection of bacteria in wastewater.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!