Polymer-coated quantum dots 'shine' inside living cells

Quantum dot with an amphiphilic polymer coating
A quantum dot with an amphiphilic polymer coating, at which other polymer chains can be 'clicked' to form new combinations with other quantum dots.

Quantum dots emit more intense and longer-lasting light than that produced by fluorescent markers, but they do not dissolve in water and pose toxicity risks for use in living organisms. Recognizing this setback, researchers at the University of Twente’s MESA+ Institute for Nanotechnology (Enschede, The Netherlands) and at the A*STAR Institute of Materials Research and Engineering in Singapore have developed a coating that allows quantum dots to be used inside the human body—even inside living cells.

The new coating enables quantum dots, which are semiconductor nanocrystals, to cast light on biomedical processes. These dots consist of several hundred to several thousand atoms that emit visible light when they are exposed to invisible UV radiation, for example, and range from a few to several tens of nanometers in size. The coating’s benefits are not limited to improved solubility in water alone. Other molecules can "lock on" to its surface, which could make coated quantum dots sensitive to certain substances, for example, or allow them to bind to specific types of cells, such as tumor cells.

The researchers developed an amphiphilic coating, which pairs hydrophobic and hydrophilic properties. The "water hating" side of the polymer material attaches to the surface of the quantum dot. Its exposed hydrophilic side then makes the quantum dot/coating combination soluble in water. The coating builds up on the surface of the quantum dot through a process of self-assembly. The coating polymer has the added benefit that other molecules can be bound to it. Another important plus is that it does not adversely affect the quantum dot’s light-emitting properties.

The researchers published their work in the October issue of Nature Protocols. For more information, please visit http://www.nature.com/nprot/journal/v6/n10/abs/nprot.2011.381.html.

-----

Follow us on Twitter, 'like' us on Facebook, and join our group on LinkedIn

Follow OptoIQ on your iPhone; download the free app here.

Subscribe now to BioOptics World magazine; it's free!

Get All the BioOptics World News Delivered to Your Inbox

Subscribe to BioOptics World Magazine or email newsletter today at no cost and receive the latest news and information.

 Subscribe Now
Related Articles

New bioimaging technique offers clear view of nervous system

Scientists at Ludwig-Maximilians University have developed a technique for turning the body of a deceased rodent entirely transparent, revealing the central nervous system in unprecedented clarity....

Fluorescent jellyfish proteins light up unconventional laser

Safer lasers to map your cells could soon be in the offing -- all thanks to the humble jellyfish. Conventional lasers, like the pointer you might use to entertain your cat, produce light by emittin...

Fluorescence microscopy helps provide new insight into how cancer cells metastasize

By using fluorescence microscopy, scientists have discovered an alternate theory on how some cancer cells metastasize.

In vivo imaging method visualizes bone-resorbing cell function in real time

In vivo imaging can visualize sites where osteoclasts (bone-resorbing cells) were in the process of resorbing bone.

BLOGS

Neuro15 exhibitors meet exacting demands: Part 2

Increasingly, neuroscientists are working with researchers in disciplines such as chemistry and p...

Why be free?

A successful career contributed to keeping OpticalRayTracer—an optical design software program—fr...

LASER Munich 2015 is bio-bent

LASER World of Photonics 2015 included the European Conferences on Biomedical Optics among its si...

White Papers

Understanding Optical Filters

Optical filters can be used to attenuate or enhance an image, transmit or reflect specific wavele...

How can I find the right digital camera for my microscopy application?

Nowadays, image processing is found in a wide range of optical microscopy applications. Examples ...

CONNECT WITH US

            

Twitter- BioOptics World

Copyright © 2007-2016. PennWell Corporation, Tulsa, OK. All Rights Reserved.PRIVACY POLICY | TERMS AND CONDITIONS