Fluorescence lights up cells programmed to die
Programmed cell death, or apoptosis, occurs tens of millions of times every day in every human body. Researchers in South Korea have devised an easy method to detect apoptotic cells by fluorescence, as they report in Chemistry—An Asian Journal.
Their method makes it easier to detect improper biological regulation of apoptosis, which can lead to neurodegenerative diseases, autoimmune diseases, and cancer.
Apoptosis is involved in macroscopic developmental processes as well. For example, in an embryo, the cells between fingers die by apoptosis to form individual digits, and the tail of a tadpole is resorbed by apoptosis when it metamorphoses into a frog.
Upon apoptosis, the relative composition of the outside and inside of the cell membrane changes, and one component, phosphatidylserine (PS), migrates from the interior to the exterior. Kyo Han Ahn and collaborators at Pohang University of Science and Technology designed an artificial membrane vesicle that fluoresces when it interacts with PS. This so-called liposome is held together by a polydiacetylene backbone and is decorated with zinc atoms at its periphery.
The zinc atoms interact with PS but not with other components of the cell membrane. This interaction distorts the shape of the backbone, causing fluorescence of the liposome. The "turn on" effect eliminates washing steps to remove extra fluorescent marker, making the method easy to use. The selectivity of the interaction means that only apoptotic cells are marked fluorescently. Microscopy images show that the fluorescence is localized on the cell surface, confirming the mode of interaction between liposome and PS.
About the Author
Kyo Han Ahn is professor of chemistry at the Pohang University of Science and Technology (POSTECH; South Korea) and director of the Center for Electro-Photo Behaviors in Advanced Molecular Systems there. His research interests include molecular recognition and sensing, nanometer sized biological functional materials, and luminescent materials.
Author: Kyo Han Ahn, Pohang University of Science and Technology (Rep. Korea), http://www.postech.ac.kr/chem/mras/index.html
Title: Turn-On Fluorescence Detection of Apoptotic Cells Using a Zinc(II)-Dipicolylamine-Functionalized Poly(diacetylene) Liposome
Chemistry - An Asian Journal, Permalink to the article: http://dx.doi.org/10.1002/asia.201201139
Kyo Han Ahn | Wiley-VCH
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...