Label-free detection of DNA methylation by surface-enhanced Raman spectroscopy using zirconium-modified silver nanoparticles.

DNA methylation is an important feature of gene epigenetics that affects the metabolic process of organisms. Although surface-enhanced Raman spectroscopy (SERS) has demonstrated great potential in label-free DNA detection, discriminating the various processes involved in DNA methylation remains a challenge. DNA molecules fold themselves, wrapping the hydrophobic bases, thus making it difficult for traditional methods to detect single-base signals.

Electrochemically renewable SERS sensor: A new platform for the detection of metabolites involved in peroxide production.

The accurate detection of hydrogen peroxide (HO)-involved metabolites plays a significant role in the early diagnosis of metabolism-associated diseases, whereas most of current metabolite-sensing systems are often hindered by low sensitivity, interference of coexisting species, or tedious preparation. Herein, an electrochemistry-regenerated surface-enhanced Raman scattering (SERS) sensor was developed to serve as a universal platform for detecting HO-involved metabolites. The SERS sensor was constructed by modifying newly synthesized 2-mercaptohydroquinone (2-MHQ) molecules on the surface of gold nanoparticles (AuNPs) that were electrochemically predeposited on an ITO electrode.

Sensitive and selective SERS probe for detecting the activity of γ-glutamyl transpeptidase in serum.

γ-Glutamyl transpeptidase (GGT) has attracted considerable attention for its regulatory effect on glutathione metabolism in living organisms; further, its close relationship with physiological dysfunctions such as hepatitis and liver cancers has enhanced its applicability. Therefore, the accurate detection of GGT levels is particularly important for the early diagnosis of diseases. Thus, we herein report the development of a surface-enhanced Raman spectroscopic (SERS) probe, namely bis-s,s'-((s)-4,4'-thiolphenylamide-Glu) (b-(s)-TPA-Glu), that comprises of a γ-glutamyl moiety for detection of the GGT activity.

Simultaneous Detection of Intracellular Nitric Oxide and Peroxynitrite by a Surface-Enhanced Raman Scattering Nanosensor with Dual Reactivity.

A functional surface-enhanced Raman scattering (SERS) nanosensor which can simultaneously detect nitric oxide (NO) and peroxynitrite (ONOO) in living cells is explored. The SERS nanosensor is fabricated through modifying gold nanoparticles (AuNPs) with newly synthesized 3,4-diaminophenylboronic acid pinacol ester (DAPBAP), which has two reactive groups. The simultaneous detection achieved in this work is not only because of the SERS spectral changes of the nanosensor resulting from the dual reactivity of DAPBAP on AuNPs with NO and ONOO but also by the narrow SERS bands suitable for multiplex detection.