A nanosheet made of organic polymers has been developed to prevent the drying and deforming of biological samples, thus enabling high-quality imaging under microscopes.
Be it cosmology or biology, the advancement of science largely relies on the advancement of measuring instruments and methodology. In the past couple of decades, scientists' passion to see the invisible has vastly improved microscopes and other equipment resulting in high-resolution images, three-dimensional images, and longer recording times of biological samples. However, current setups do not prevent them from drying and deforming during observations, resulting in blurred images.
Scientists from Hokkaido University and Tokai University in Japan have developed a nanosheet made of a fluorine-containing polymer known as CYTOP® and investigated its effectiveness in producing clear images when wrapped around biological samples. CYTOP® is a commercially available chemical agent developed by Asahi Glass Co., Ltd.
The researchers successfully produced a nanosheet of CYTOP® by spreading its solution on a layer of poly-vinyl-alcohol (PVA). The nano-thin layer of CYTOP® was easily detached from the PVA layer by soaking them in water. The thickness of the nanosheet could be adjusted by changing the concentration of its solution. The nanosheet retained CYTOP®'s high water repellent properties which should help retain a sample's water content when used as wrapper.
The team then tested the nanosheet's wrapping properties by using alginate hydrogel to simulate biological samples such as tissue. They found that the gel retained 60% of its water content after 24 hours when wrapped whereas the unwrapped gel became totally dehydrated after about 10 hours.
Experimenting with various thicknesses, they found that a 133-nm-thick sheet provides sufficient water retention and surface adhesion which is necessary for fixing samples to the cover slip.
They next applied an actual biological sample: 1-mm thick brain slices from mice. Without a CYTOP® wrap, evaporation of the embedded water caused local, non-uniform sample shrinkage, leading to blurred images. By wrapping the brain slices in a CYTOP® nanosheet, however, images with a high spatial resolution could be obtained from scanning a large area (more than 750 μm x 750 μm) over a long time (about 2 hours).
Similar results were obtained even when the sample was embedded in agarose gel -- a common technique used for mounting biological tissues that could disturb the clarity of taransparentized samples -- without disturbing the clarity.
"The wrapping technique is still at an early stage, but it establishes and verifies the superiority of nanosheet wrapping for tissue imaging," say the researchers of the paper published in Advanced Materials.
Naoki Namba | EurekAlert!
Contacting the molecular world through graphene nanoribbons
19.02.2018 | Elhuyar Fundazioa
When Proteins Shake Hands
19.02.2018 | Friedrich-Schiller-Universität Jena
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.
But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...
Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.
The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...
Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters
Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
19.02.2018 | Materials Sciences
19.02.2018 | Materials Sciences
19.02.2018 | Life Sciences