The live visualization with fast kinetics of the interaction between cells has been long term challenges because of the lack of efficient stimulation methods. We propose an approach to achieve single cell resolution stimulation and FRET-base calcium live cell imaging to visualize fast kinetics of calcium transport between physically connect neighboring cells. Chemical stimulation stimulates cells within a dish at the same time and is not suitable for the study of cell-cell interaction. We replaced chemical stimulation with ultrasound-based mechanical stimulation approach to provide precise spatiotemporal resolution. To achieve this, we integrated 3D translation stages and epi-fluorescence microscope and a developed 150 MHz high frequency ultrasound with f number of 1 and aperture size of 1 mm. The 150 MHz transducer can focus within 10 micrometers in diameter and directly stimulate cells by disturbing cell plasma membranes without microbubbles. High frequency stimulation was used to introduce calcium ions into cytoplasm of cells. Results demonstrate calcium transport between cells, visualized by FRET calcium biosensor after only one cell was stimulated by the developed high frequency ultrasonic transducer.
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Fluorescence Resonance Energy Transfer Measurements in Polymer Science: A Review
Fluorescence resonance energy transfer (FRET) is a non‐invasive characterization method for studying molecular structures and dynamics, providing high spatial resolution at nanometer scale. Over the past decades, FRET‐based measurements are developed and widely implemented in synthetic polymer systems for understanding and detecting a variety of nanoscale phenomena, enabling significant advances in polymer science. In this review, the basic principles of fluorescence and FRET are briefly discussed. Several representative research areas are highlighted, where FRET spectroscopy and imaging can be employed to reveal polymer morphology and kinetics. These examples include understanding polymer micelle formation and stability, detecting guest molecule release from polymer host, characterizing supramolecular assembly, imaging composite interfaces, and determining polymer chain conformations and their diffusion kinetics. Finally, a perspective on the opportunities of FRET‐based measurements is provided for further allowing their greater contributions in this exciting area.
more » « less- NSF-PAR ID:
- 10386734
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Rapid Communications
- Volume:
- 43
- Issue:
- 24
- ISSN:
- 1022-1336
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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