Fluorescence method can detect tumor markers easily

It is time-consuming and expensive to identify specialized tumor markers that indicate the presence of cancer, even though blood is teeming with proteins. Realizing this, researchers in the Project Group for Automation in Medicine and Biotechnology (PAMB) of the Fraunhofer Institute for Manufacturing Engineering and Automation (IPA; Mannheim, Germany) have developed a new fluorescence method that enables cancer diagnosis to be carried out in a single step.

Related: 'Smart beacons' target cancer tumors

Related: Fluorescence microscopy aids in melanoma development discovery

Tumor markers in the blood help determine whether the patient is afflicted with a malignant tumor and whether it is excreting markers more vigorously—involving highly specific proteins. An increased concentration in the blood provides one indication of the disease for physicians, but it is expensive and time-consuming to detect the markers due to the large amount of molecules and proteins present in blood. To be able to detect a single, specific protein, doctors must first separate and purify the blood in several steps, and then isolate the marker they are searching for from the rest of the molecules.

Concentration of biological molecules in a sample can be observed visually using laser-stimulated fluorescence
Concentration of biological molecules in a sample can be observed visually using laser-stimulated fluorescence. (Image courtesy of Fraunhofer IPA)

To that end, the researchers developed a one-step fluorescence analysis method that improves signal-to-noise ratio in recognizing individual molecules in blood samples, says Caroline Siegert, a scientist at IPA. First, they used magnetic beads (particles measuring a few micrometers in size with a magnetic core) that, when positioned using an external magnet on the test tube, can be halted or steered. To isolate molecules from blood (or other biological samples), the researchers coated the surface of the beads with specialized antibodies. If the proteins that are being searched for meander past the beads, the antibodies grab hold of them. By holding a magnet to the outside of the test tube, the beads—together with the desired proteins—stick to the interior surface of the tube, while the rest of the solution can be easily removed. Also, the samples and investigation are not just exposed to the coated beads, but also to additional antibodies that have fluorescent markers bound to them. These antibodies attach themselves to the proteins being searched for and cause them to glow. The optical signal is very weak, though, and would normally disappear in the background noise. By applying an alternating magnetic field, the magnetic beads flock together in rhythm and the fluorescent markers bound to the surfaces emit their light in sync—and radiate considerably more brightly than any given bead by itself. The advantage of this visualization method is that the optical signal provides immediate insight about whether a tumor marker protein is present in the blood.

The new method not only detects numerous biological molecules such as antibodies, but also nucleic acids that indicate an infection. “Since we use conventional beads, it means the molecules can be quickly and simply isolated after the analysis as well,” Siegart says.

The researchers will present results using their method at the Analytica international trade fair, to be held April 1-4, 2014, in Munich, Germany (Hall A1, Booth 530).


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.


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 ...



Twitter- BioOptics World

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