Real-Time Nanoscale Investigation of Soft Matter Defects
Research areas:
Optics, Quantum Optics, Atoms, Molecules, Plasmas
Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
Polymer Materials
Project leaders:
Ermakova, Anna, Dr.
Max-Planck-Institute for Polymer Research
Ackermannweg 10, 55128 Mainz
+49 (0)6131-379-311
anna.ermakova[a]mpip-mainz.mpg.de
Budker, Dmitry, Univ.-Prof. Dr.
Johannes Gutenberg University Mainz
Department of Physics (QUANTUM)
Staudingerweg 18, 55099 Mainz
+49 (0)6131-39-29630
budker[a]uni-mainz.de
Summary
The soft matter properties and applications strongly depend on their purity and can be changed dramatically
in the presence of defects. Contemporary attempts to study defects in soft matter rely mainly on optical (e.g., widefield microscopy, fluorescence microscopy, etc.) or electron and X-ray imaging techniques. These
methods mainly focus on structural imaging and defect localization rather than their dynamic processes such as migration or transformation of soft matter defects.
An entirely new technique is required for studying defect dynamics, which would enable sufficiently fast
detection of ultra-low electrical currents with high resolution, down to the level of single defects.
The main goal of our project is the real-time investigation of nanoscale dynamic processes inside single self-
assembling peptide nanofibers and their formation mechanisms using nanodiamonds with color centers. This
project aims to answer fundamental questions related to nanofiber and nanogel formation. Particularly our
novel experimental method will contribute to the understanding, of whether nanofiber growth occurs by
extension at their ends or by incorporation of new peptide units into the existing nanofiber. Furthermore, this
will allow for observation of possible movement or migration of nanofibers and their peptide units inside a
nanogel system. The experimental technique used in this research is based on the quantum properties of
nitrogen-vacancy centers in nanodiamonds, which are sensitive to external magnetic fields. Therefore, some
building units of peptide nanofibers will be labeled with magnetic nanoparticles and some with nanodiamonds
containing nitrogen-vacancy centers (Figure 1A). The relative positions between magnetic particles and
nanodiamonds will be detected during the formation of nanofibers. We expect to observe the dynamic
processes of structural changes within a single nanofiber (Figure 1B) as well as within 2D and 3D hydrogel
nanofiber systems (Figure 1C). Subsequently, this novel experimental technique developed within our project can be applied to other soft materials such as organic semiconductors and liquid crystals to better understand them and, ultimately, improve their properties for technological applications.
Figure 1. (A) Investigation of dynamical processes of peptide movement in nanofibers via measurements of
the distance between a nanodiamond (ND) and magnetic particle (MP), which are attached to peptide units.
(B) Investigation of dynamical processes of the nanofiber growth by measuring the distance between the
nanodiamond and magnetic particle, which are attached to peptide units. (C) Nanodiamonds with NV centers incorporated into hydrogel matrix for 3D imaging of structural defects and electric field distribution inside the material.