The research group of YANG Liangbao at the Institute of Health and Medical Technology, Hefei Institutes of Physical Science (HFIPS), Chinese Academy of Science (CAS) has recently developed a Surface-enhanced Raman Spectroscopy (SERS) method to automatically capture target molecules in AgNP/MoS2 nano-pockets, which enables highly sensitive and long-duration dynamic detection of some chemical reaction processes.
The results were published in Analytical Chemistry and selected as the front cover.
SERS is a kind of molecular spectroscopy with fast, highly sensitive, and fingerprint identification properties.
"This research is based on our previous SERS studies." said Prof. YANG Liangbao, "which we have been engaging in for years."
In this experiment, the team covered a large-area monolayer nanoparticle film with a two-dimensional material called MoS2, and created an AgNP/MoS2 nano "pocket". This nano "pocket" was then placed on the target molecules to be tested. Using a multi-physics field model and finite element simulation method, the team analyzed the electric field enhancement distribution of the AgNP/MoS2 nano "pocket" structure in both solution and air, as well as the dynamic process of solution evaporation.
They found that the nano "pocket" not only possessed a high density of hotspots but also had the ability to actively capture molecules. Compared to a single-layer Ag NP film, the addition of MoS2 slowed down the evaporation of the solution, extending the window of SERS detection and further enhancing the electric field. This structure enabled high sensitivity and stability in dynamic SERS detection for up to 8 minutes.
Additionally, this structure can be utilized for detecting anti-tumor drugs and monitoring structural changes of xanthine in serum.
The related methods are expected to be more applicable to the in-situ detection of substance transformations or other chemical reaction kinetics in biological systems, according to the team.
This research was funded by the Research Instrument and Equipment Development Program of the Chinese Academy of Sciences, the National Natural Science Foundation of China, and the Natural Science Research Program of Anhui Province.
Front cover of Analytical Chemistry (Image by CHEN Siyu)
(top) AgNP/MoS2 nano-pockets" formed by assembling a large-area monolayer nanoparticle film at the liquid-liquid interface (bottom) in a large-area monolayer nanoparticle film covered with the two-dimensional material MoS2 (Image by CHEN Siyu)
