Features | Partner Sites | Information | LinkXpress
Sign In
GLOBETECH PUBLISHING
GLOBETECH PUBLISHING
JIB

Untethered Microgrippers Sample Biologic Tissue

By BiotechDaily International staff writers
Posted on 13 May 2013
Image: A single μ-gripper next to a catheter (Photo courtesy of Johns Hopkins University).
Image: A single μ-gripper next to a catheter (Photo courtesy of Johns Hopkins University).
A new study describes thermally activated microgrippers that can reach narrow conduits in the body and be used to excise tissue for diagnostic analyses and biopsies.

Researchers at Johns Hopkins University (JHU; Baltimore, MD, USA) designed the submillimeter endoscopic microgrippers (μ-grippers) to resemble biological appendages, such as hands, with rigid phalanges and flexible joints. The residual stress powered actuators allow them to close and grasp without the need for tethers, while the rigid phalanges of the μ-grippers are composed of nickel, and hence, respond to an applied magnetic field. A thermo-sensitive polymer trigger layer on the joints keeps the μ-grippers flat at 4 °C, but softens at 37 °C, causing the μ-grippers to close.

The μ-grippers are small enough that hundreds can be deployed at a time and actuated en masse, and could therefore form the basis for a more statistically efficient means to screen large surface area organs such as the colon. To test the feasibility of biologic tissue sampling with μ-grippers, the researchers used a swine colon in ex vivo studies. They uniformly spread hundreds of μ-grippers by rotating the endoscope during the deployment. The arms of each millimeter-long μ-gripper is composed of chromium and gold actuators that naturally want to bend inwards, but are held back by the thin layer of polymer coating.

To simulate the normal human temperature, the colon was submerged in a water bath kept at 37 °C, whereupon the coating dissolved and the talons snatched up cells at close proximity; the researchers then visually verified the closure of the μ-grippers using endoscopic imaging. After closure, the vast majority of μ-grippers were retrieved using a magnetic catheter inserted through the endoscope. The researchers found that the μ-grippers identified the lesion 45% of the time; when the swarm was boosted up to 1,500 μ-grippers, the efficiency rose to 95%. The study was published in the April 2013 issue of Gastroenterology.

“Our results suggest a new paradigm in medicine whereby large numbers of small, tether-free microsurgical tools could complement individual, large, tethered biopsying devices,” concluded lead author Evin Gultepe, PhD, and colleagues of the department of chemical and biomolecular engineering. “The tissue retrieved by the μ-grippers is of sufficient quality and quantity to allow DNA and RNA extraction, as well as polymerase chain reaction (PCR) amplification in an effort to look for previously identified disease-diagnostic markers.”

Related Links:

Johns Hopkins University



comments powered by Disqus

Channels

Genomics/Proteomics

view channel
Image: This micrograph depicts the presence of aerobic Gram-negative Neisseria meningitidis diplococcal bacteria; magnification 1150x (Photo courtesy of the CDC - US Centers for Disease Control and Prevention).

Infection by Meningitis Bacteria Depends on Dimerization State of Certain Host Cell Proteins

A team of molecular microbiologists has untangled the complex three-way interaction between the non-integrin laminin receptor (LAMR1), galectin-3 (Gal-2), and the pathogenic bacterium Neisseria meningitidis.... Read more

Drug Discovery

view channel

Molecule in Green Tea Used as Carrier for Anticancer Proteins

A molecule that is a key ingredient in green tea can be employed as a carrier for anticancer proteins, forming a stable and effective therapeutic nanocomplex. This new discovery could help to construct better drug-delivery systems. Some cancer treatments depend on medication comprising the therapeutic drug and a carrier... Read more

Lab Technologies

view channel
Image: Yale West Campus is organized into research institutes and core facilities — all designed to promote collaboration and interdisciplinary dialogue (Photo courtesy of Yale University).

American and European Partners Establish a Microscopy Center of Excellence

A prominent American university has announced a partnership agreement with a major European producer of microscopes and imaging tools that will establish a center for the use of cutting-edge imaging technologies... Read more

Business

view channel

Interest in Commercial Applications for Proteomics Continues to Grow

Increasing interest in the field of proteomics has led to a series of agreements between private proteomic companies and academic institutions as well as deals between pharmaceutical companies and novel proteomics innovator biotech companies. Proteomics is the study of the structure and function of proteins.... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.