Shape-Shifting Nanoprobes Report on Internal Body Conditions Using Magnetic Fields

by Bidita Debnath on April 13, 2015 at 11:27 PM

Shape-Shifting Nanoprobes Report on Internal Body Conditions Using Magnetic Fields
Researchers have devised and demonstrated new shape-shifting probe devices that will be able to detect and measure localized conditions on the molecular scale deep within tissues.

National Institute of Standards and Technology (NIST) and the National Institutes of Health (NIH) scientists' new, shape-shifting probe is about 5 to 10 times smaller than a single red blood cell, one of the smallest human cells and is capable of sensitive, high-resolution remote biological sensing that is not possible with current technology.

Lead author Gary Zabow said that instead of optically based sensing, the shape-changing probes are designed to operate in the radio frequency (RF) spectrum, specifically to be detectable with standard nuclear magnetic resonance (NMR) or magnetic resonance imaging (MRI) equipment. In these RF ranges, signals are, for example, not appreciably weakened by intervening biological materials. As a result, they can get strong, distinctive signals from very small dimensions at substantial depths or in other locations impossible to probe with optically based sensors.

The novel devices, called geometrically encoded magnetic sensors (GEMs), are micro engineered metal-gel sandwiches and each consists of two separate magnetic disks that range from 0.5 to 2 micrometers (millionths of a meter) in diameter and are just tens of nanometers (billionths of a meter) thick.

Scientists tested the sensors in solutions of varying pH, in solutions with ion concentration gradients and in a liquid growth medium containing living canine kidney cells as their metabolism went from normal to nonfunctional in the absence of oxygen. That phenomenon caused the growth medium to acidify and the change over time was sensed by the GEMs and recorded through real-time shifting in resonant frequencies. Even for the un-optimized, first-generation probes used, the frequency shifts resulting from changes in pH were easily resolvable and orders of magnitude larger than any equivalent frequency shifting observed through traditional magnetic resonance spectroscopy approaches.

One of the most significant features of GEMs is that they can be "tuned" in fabrication to respond to different biochemical states and to resonate in different parts of the RF spectrum by altering the gel composition and the magnet shapes and materials, respectively. So placing two different populations of GEMs at the same site makes it possible to track changes in two different variables at the same time.

Zabow added that they think that these sensors can potentially be adapted to measure a variety of different biomarkers, possibly including things such as glucose, local temperatures, various ion concentrations, possibly the presence or absence of various enzymes and so forth.

The study appears online in the journal Nature.

Source: ANI

News A-Z
News Category
What's New on Medindia
Stroop Effect
Plant-Based Diet may Reduce the Risk of COVID-19
Lower Respiratory Tract Infections Linked to Obstructive Sleep Apnea in Children
View all

Medindia Newsletters Subscribe to our Free Newsletters!
Terms & Conditions and Privacy Policy.

More News on:
Healthy Living 

Recommended Reading
People Willing to Donate Tissue Samples to Biobank: Survey
Majority of people were willing to donate tissue samples and medical information to a biobank for .....
Experts Describe New Approach to Promote Regeneration of Heart Tissue
Adult mammals have low level of cardiac muscle cell; so their heart tissues have limited capacity .....
Cherenkov Emission Measures Radiation Dose Delivered to Tissues
Cherenkov radiation is emitted when electrons are fired through water at a speed faster than the ......
Woman Gives Birth to Twins After Ovarian Tissue Transplant into Abdomen
An Australian lady named Vali Creus, has become the first and so far the only woman in the world ......

Disclaimer - All information and content on this site are for information and educational purposes only. The information should not be used for either diagnosis or treatment or both for any health related problem or disease. Always seek the advice of a qualified physician for medical diagnosis and treatment. Full Disclaimer

© All Rights Reserved 1997 - 2021

This site uses cookies to deliver our services. By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use