Related Experiment Video
Updated: Feb 4, 2026

Optical Trapping of Plasmonic Nanoparticles for In Situ Surface-Enhanced Raman Spectroscopy Characterizations
Published on: June 23, 2022
Laser trapping/confocal Raman spectroscopic characterization of PLGA-PEG nanoparticles
Jie Yang1, Ruo-Nan Zhang1, Dong-Jie Liu1
1College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China. yanhu@zzu.edu.cn.
Abstract:
We have immobilized poly(ethylene glycol) (PEG) on the surfaces of poly(lactic-co-glycolic acid) (PLGA) nanoparticles by two different chemical methods, i.e., SOCl2 halogenate-alcoholysis and DCC dehydration. The immobilized PLGA nanoparticles were characterized by DLS, 1H NMR, FT-IR and laser trapping/confocal Raman spectroscopic techniques. As a result, especially the Raman spectra which were measured after optically trapping ca. 10 individual nanoparticles in solution indicated that the PLGA nanoparticles were successfully immobilized with the PEG by the chemical methods.
Related Concept Videos
Social Traps
Raman Spectroscopy: Overview
However, a small fraction of the scattered light exhibits a frequency shift due to the exchange of energy between the incident photons and...
Raman Spectroscopy Instrumentation: Overview
The monochromatic laser source, typically using visible or near-infrared radiation, generates a highly focused beam of light. This light interacts with the molecules of the sample, scattering some of the light. Liquid and gaseous samples are usually tested in ordinary glass capillaries, while solids can be analyzed as powders packed in capillaries or as potassium...
Confocal Fluorescence Microscopy
Matrix-Assisted Laser Desorption Ionization (MALDI)
Colloids

