Stimuli-responsive surface-enhanced Raman scattering (SERS) nanoparticles have been developed by using colloidal gold nanocrystals and a class of thiolated block copolymers consisting of a pH-responsive polymer segment, an amphiphilic polyethylene glycol segment, and a lipoic acid anchoring group. The results demonstrate that SERS signals can be switched on and off by molecular conformations in response to pH. An important finding is that neutralized polymethacrylic acid (PMAA) molecules are able to interact with amphiphilic polyethylene glycol (PEG) chains, leading to highly compact and intermingled copolymer structures on the surface of nanoparticles. This type of molecular conformation change provides a new strategy for controlling plasmonic coupling and electromagnetic Raman enhancement and raises the possibility of using SERS nanoparticle tags for biomolecular binding and enzymatic cleavage studies.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2703497 | PMC |
http://dx.doi.org/10.1021/ja902226z | DOI Listing |
Mikrochim Acta
January 2025
College of Chemistry and Chemical Engineering, Xinjiang Normal University, Urumqi, 830054, China.
A AuNSs@PB@Ag-Apt surface-enhanced Raman scattering (SERS) probe has been developed by embedding Prussian blue (PB) between Au core and Ag shell. The PB SERS probe illustrates strong SERS activity in the Raman silent region of 2070 cm, and has a zero background signal, ensuring high sensitivity for the detection of Staphylococcus aureus (S. aureus).
View Article and Find Full Text PDFACS Nano
January 2025
Department of Chemistry, Seoul National University, Gwanak-ro 1, Gwanak-gu, Seoul 08826, South Korea.
Surface-enhanced Raman scattering has been widely used for molecular/material characterization and chemical and biological sensing and imaging applications. In particular, plasmonic nanogap-enhanced Raman scattering (NERS) is based on the highly localized electric field formed within the nanogap between closely spaced metallic surfaces to more strongly amplify Raman signals than the cases with molecules on metal surfaces. Nanoparticle-based NERS offers extraordinarily strong Raman signals and a plethora of opportunities in sensing, imaging and many different types of biomedical applications.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Laboratory of Toxicant Analysis, Academy of Military Medical Sciences, Beijing 100850, China. Electronic address:
Organophosphorus nerve agents (OPNAs) are highly lethal chemical warfare agents (CWAs), which poses a serious threat to human health and safety. The accurate and rapid identification of OPNAs is crucial for medical diagnosis and effective treatment. However, distinguishing between various OPNAs and their analogues using on-site point-of-care testing (POCT) remains challenging.
View Article and Find Full Text PDFACS Sens
January 2025
The Education Ministry Key Lab of Resource Chemistry, Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Municipal Education Committee Key Laboratory of Molecular Imaging Probes and Sensors, and Department of Chemistry, Shanghai Normal University, Shanghai 200234, P. R. China.
Microneedle (MN) sensors have great promise for food safety detection, but the rapid preparation of MNs for surface-enhanced Raman scattering (SERS) sensors with tunable and homogeneous nanoparticles remains a great challenge. To address this, a SERS sensor of gold nanoparticles@polydopamine@poly(methyl methacrylate) MN (AuNPs@PDA@PMMA-MN) was developed. The extended-Derjaguin-Landau-Verwey-Overbeek theory was applied to calculate the interaction energy between AuNPs and PDA.
View Article and Find Full Text PDFRSC Adv
January 2025
The Center for Chemical Biology, School of Fundamental Science and Technology, Graduate School of Science and Technology, Keio University 3-14-1 Hiyoshi, Kohoku-ku Yokohama 223-8522 Japan +81-45-566-1580 +81-45-566-1839.
We prepared a cellulose nanofiber (CNF)-based porous membrane with three dimensional cellular structures. CNF was concentrated a surfactant-induced assembly by mixing CNF with a cationic surfactant, domiphen bromide (DB). Furthermore, they were accumulated by centrifugation to obtain a CNF-DB sol.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!