Abstract
We report the application of an optical microscope equipped with a high-resolution dark-field condenser for detecting dynamic responses of cellular nanostructures in real time. Our system provides an easy-to-use technique to visualize biological specimens without any staining. This system can visualize the dynamic behavior of nanospheres and nanofibers, such as F-actin, at the leading edges of adjacent neuronal cells. We confirmed that the nanofibers imaged with this high-resolution optical microscopic technique are F-actin by using fluorescence microscopy after immunostaining the F-actin of fixed cells. Furthermore, cellular dynamics are enhanced by applying noncontact electric field stimulation through a transparent graphene electric field stimulator. High-resolution label-free optical microscopy enables the visualization of nanofiber dynamics initiated by filopodial nanofiber contacts. In conclusion, our optical microscopy system allows the visualization of nanoscale cellular dynamics under various external stimuli in real time without specific staining.
Highlights
Microscopic bioimaging systems have rapidly progressed along with advances in immunostaining methods, and these systems are being used to investigate basic mechanisms of cell proliferation and differentiation.[1,2] In addition, microscopic bioimaging is effective for studying in real-time dynamics[3,4,5] of living cells responding to external stimuli.[6,7] In the past, conventional optical imaging (COI) has been a popular choice for observing real-time cellular structures and dynamics simultaneously, as COI has a large field-of-view (FOV) and easy accessibility
The imaging system is adapted from an inverted COI system with a live cell incubation system operated at 37°C and 5% CO2 [Fig. 1(a)]
In nanoscale optical imaging (NOI), the condenser was put into the culture dish with cell media and positioned at a submillimeter distance above the cells, while the condenser of the COI was positioned several centimeters from the cells
Summary
Microscopic bioimaging systems have rapidly progressed along with advances in immunostaining methods, and these systems are being used to investigate basic mechanisms of cell proliferation and differentiation.[1,2] In addition, microscopic bioimaging is effective for studying in real-time dynamics[3,4,5] of living cells responding to external stimuli.[6,7] In the past, conventional optical imaging (COI) has been a popular choice for observing real-time cellular structures and dynamics simultaneously, as COI has a large field-of-view (FOV) and easy accessibility. Other contrast-enhanced COI techniques have been developed, such as photonic crystal slabs microscopy[8] and reflection interference contrast microscopy.[9] their spatial resolution is similar to that of the conventional microscopy. As a result, these COI techniques still have difficulty in detecting nanometer-sized cytoskeletal elements, for example, F-actin, a key molecule involved in cellular dynamics.[10] a high-resolution real-time imaging system is needed to study nanostructure dynamics
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
