Fluorescence-producing, self-powered microfluidic chip detects cancer fast

Researchers at the RIKEN Advanced Science Institute (Wako, Japan) have developed a self-powered microfluidic chip that can perform an analysis for cancer-specific microRNAs in a drop of patient blood in as little as 20 minutes. Claimed as the most sensitive microRNA detector yet, if enough of the target is present, the chip produces a fluorescence signal that can be detected using a fluorescence microscope.

Early detection is vital for the effective treatment of cancer. In many cases, tell-tale biomarkers are present in the bloodstream long before outward symptoms become apparent. Early-stage cancers, for example, release tiny quantities of biomolecules called microRNAs into the blood. The development of an inexpensive and rapid point-of-care diagnostic test capable of spotting such early biomarkers of disease could therefore save many lives.

The test developed by Kazuo Hosokawa and colleagues at Riken is inexpensive to make and relies on an internal pressure gradient to pump the sample through the microchannels, thus eliminating the need for an external power supply—features that make the system highly suitable for practical point-of-care disease diagnosis. Previous versions of the chip, however, could only detect microRNA at concentrations far above those required for early cancer detection.

A self-powered microfluidic chip for cancer biomarker detection. The sample and two fluorescence amplification reagents are added to the three inlet ports. The presence of cancer biomarkers can be detected by fluorescence in the main microfluidic channel
A self-powered microfluidic chip for cancer biomarker detection. The sample and two fluorescence amplification reagents are added to the three inlet ports. The presence of cancer biomarkers can be detected by fluorescence in the main microfluidic channel.

In their latest work, Hosokawa and co-workers increased the chip's sensitivity by boosting the intensity of fluorescence generated by a positive test. The original chip worked by immobilizing target microRNA on probe DNA in the main microchannel, where each bound site produced a fluorescent signal. In the new chips, the researchers added a fluorescence amplification process that involves passing two amplification reagents over the immobilized microRNA. The reagents—a fluorescent tag and a branched linker—bind to immobilized microRNA to form tree-like dendritic structures that amplify the fluorescence signal by up to 1,000 times. Using this amplification process, the researchers were able to improve the sensitivity of the device to a level approaching that required for early cancer detection.

The next step for the team will be to further simplify the device by eliminating the need for a fluorescence microscope, which will involve replacing the fluorescent tags with some other form of marker. "That is a very important direction for future development," says Hosokawa. "We are planning the use of different labelling materials instead of the fluorescent dye, such as gold particles, which would enable naked-eye detection."

Their work appears in the journal PLoS One; for more information, please visit http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0048329.

-----

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

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