Abstract
The morphogenesis of supramolecular assemblies is a highly dynamic process that has only recently been recognized, and our understanding of this phenomenon will require imaging techniques capable of crossing scales. Shape transformations depend both on the complex energy landscapes of supramolecular systems and the kinetically controlled pathways that define their structures and functions. We report here the use of confocal laser scanning microscopy coupled with a custom-designed variable-temperature sample stage that enables in situ observation of such shape changes. The submicrometer resolution of this technique allows for real-time observation of the nanostructures in the native liquid environments in which they transform with thermal energy. We use this technique to study the temperature-dependent morphogenic behavior of peptide amphiphile nanofibers and photocatalytic chromophore amphiphile nanoribbons. The variable-temperature confocal microscopy technique demonstrated in this work can sample a large volume and provides real-time information on thermally induced morphological changes in the solution.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 4234-4241 |
| Number of pages | 8 |
| Journal | Nano letters |
| Volume | 20 |
| Issue number | 6 |
| DOIs | |
| State | Published - Jun 10 2020 |
Funding
This work was supported by the Center for Bio-Inspired Energy Science, an Energy Frontier Research Center funded by the U.S. DOE, Office of Science, Basic Energy Sciences, under award no. DE-SC0000989. The authors thank Salomon Rodriguez for his advice and assistance with stage machining and assembly. The authors also thank Eric Earley and the McCormick Graduate Leadership Council for SolidWorks CAD training, Eric Bruckner (Stupp Laboratory, Northwestern University) for synthesizing additional PMI-CA-1 molecules in the revision of this manuscript, and Mark E. Seniw for assistance with graphics. Synthesis of the peptide amphiphiles was performed at the Peptide Synthesis Core Facility of the Simpson Querrey Institute at Northwestern University, which has current support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205). This work made use of the Keck Biophysics facility (fluorescence measurements) and the Northwestern University Research Student Shop (machining and fabrication). The Keck Biophysics facility received support from a Cancer Center Support Grant (NCI CA060553). The Research Student Shop received support from the Northwestern University Office for Research Shared and Core Facilities. This work also made use of the BioCryo facility of Northwestern University’s NUANCE Center, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205); the MRSEC program (NSF DMR-1720139) at the Materials Research Center; the International Institute for Nanotechnology (IIN); and the State of Illinois, through the IIN. Nuclear magnetic resonance spectroscopy and mass spectroscopy equipment at the Integrated Molecular Structure Education and Research Center was supported by the National Science Foundation under CHE-9871268. It also made use of the CryoCluster equipment, which has received support from the MRI program (NSF DMR-1229693). The work utilized a license of the SolidWorks CAD program provided by the McCormick School of Engineering and Applied Sciences.
Keywords
- confocal microscopy
- in situ microscopy
- nanofibers
- nanoribbons
- supramolecular assembly
ASJC Scopus subject areas
- Condensed Matter Physics
- Mechanical Engineering
- Bioengineering
- General Chemistry
- General Materials Science