Research


Overview

Synthetic polymers are heterogeneous systems composed of molecules with different molecular weight and chemical structure. The polydispersity of polymer molecules, which influences both the processing and the performance of polymer materials. is intrinsically generated from the heterogeneity in polymerization kinetics among individual polymer molecules during the synthesis process.

Our research will be focused on the studies of polymerization reactions and polymer physical properties using Magnetic Tweezers and Single-molecule Localization Microscopy, aiming to (1) explore the origin of the heterogeneity in polymerization kinetics and (2) establish the structure-property relationship of polymer materials on molecular level.


Research Interests

1. Real-time visualization of living polymerization reactions at single molecule level

2. Characterization of the physical properties of single chains

3. Inter-chain interactions and single-chain behaviors in bulk materials

4. Polymer-surface interactions


Single-molecule Microscopes in Our Lab

Magnetic Tweezers (MT)

MT uses external magnetic field to exert stretching forces onto a single polymer chain tethered between the surface and the magnetic particle. The physical properties of the polymer chains can be extracted, such as the contour length and bending stiffness.

More about MT:

Single Polymer Growth Dynamics”. Science, 2017, 358, 352-355.

Quantitative Guidelines for Force Calibration through Spectral Analysis of Magnetic Tweezers Data“. Biophys. J., 2010, 99, 1292-1302.

Quantitative Modeling and Optimization of Magnetic Tweezers“. Biophys. J., 2009, 96, 5040-5049.

Magnetic tweezers: micromanipulation and force measurement at the molecular level“. Biophys. J., 2002, 82, 3314-3329.

Single-molecule Localization Microscopy (SMLM)

SMFM captures the fluorescent signals from single fluorescent objects under laser excitation. The objects could be organic dyes, fluorescent proteins, nanoparticles or polymers. The location of the objects can be determined within a range of tens of nanometers.

More about SMLM:

Super-resolution imaging of nonfluorescent reactions via competition“. Nat. Chem., 2019, 11, 687-694.

Sub-particle reaction and photocurrent mapping to optimize catalyst-modified photoanodes“. Nature, 2016, 530, 77-80.

Concentration and chromosome-organization dependent regulator unbinding from DNA for transcription regulation in living cells”. Nat. Commun., 2015, 6, 7445

Single Particle Tracking Measurements Confirm GM1 Clustering in Solid Supported Bilayers”. J. Am. Chem. Soc., 2012, 134, 15832-15839