Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality

Abstract:
Even tiny amounts of viruses can have disastrous consequences. RNA identification can reveal the type of virus present. A fast and sensitive technique based on optical detection has now been outlined in the journal Angewandte Chemie. Scientists from Germany and Finland have demonstrated the binding of an RNA target to a probe made of gold nanorods and a DNA origami structure. Chirality switches triggered by binding can be measured by circular dichroism spectroscopy.

Viral RNA sensing: Optical detection of picomolar concentrations of RNA using switches in plasmonic chirality

MALDEN, MA | Posted on September 21st, 2018

Identifying the pathogen--often a virus--that is troubling a patient is among the biggest challenges in healthcare. Viruses responsible for Zika fever, AIDS, and hepatitis C contain mutating RNA sequences. Physicians need to know quickly which type of virus their patients have acquired, but current techniques based on multiplying RNA are costly and time-consuming. Now, Tim Liedl from Ludwigs-Maximilians-Universität in Munich, Germany, and his colleagues, have developed a fast detection strategy based on nanoplasmonics, DNA origami, and an optical readout.

Light can induce plasmonic waves in nanosized metal structures smaller than the wavelength of the incident light. This resonance may lead to strongly enhanced light emission even from nanoscopic structures--a feature that is highly interesting for biosensing applications. Liedl and colleagues have created a nanosized sensing probe for RNA molecules.

The probe, a nanosized apparatus made of DNA and gold nanorods, was assembled by the so-called DNA origami technique, which exploits the specific interactions of the DNA bases to fold and glue together single strands in any desired form. The authors constructed two bars of parallel DNA helices loosely connected through a hinge in the middle of the bars. Gold nanorods were placed on top of each of the crossed bars. Both crossing arms were supplied with functionality at their ends: the scientists attached one single DNA sequence complemented with a blocking strand to one arm, and the complementing DNA sequence to the other. In the presence of target RNA, which could be a typical viral RNA sequence, the blocking strand would leave its DNA in favor of RNA hybridization, and both single DNA sequences would complementarily form a double strand whereby the two arms of the cross are pulled together. This structural change introduces chirality to the probe.

Chirality can be detected with circular dichroism. And indeed, the structural changes triggered by the RNA binding induced a circular dichroism signal detectable with a CD spectrometer. Concentrations as low as 100 picomolar of the target RNA were recognized, according to the authors. The scientists hope to establish this technique in lab-on-a-chip systems where few steps are required for sample preparation and low-cost miniature devices lead to sensitive results. Preliminary results on serum from blood with added viral RNA were promising.

The authors admit that the detection limits are still not low enough to be clinically relevant. However, they believe improvements should be possible; including, better protection of the nanosensors from serum proteins, a change to better resonating plasmonic metals, and expansion of RNA recognition sites. This could make the technique a promising diagnostic tool that is not necessarily limited to viral RNA.

####

For more information, please click here

Contacts:
Mario Mueller

Copyright © Wiley

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

RELATED JOURNAL ARTICLE:

About the Author

Related News Press

News and information

Researchers develop artificial building blocks of life March 8th, 2024

How surface roughness influences the adhesion of soft materials: Research team discovers universal mechanism that leads to adhesion hysteresis in soft materials March 8th, 2024

Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

Imaging

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

First direct imaging of small noble gas clusters at room temperature: Novel opportunities in quantum technology and condensed matter physics opened by noble gas atoms confined between graphene layers January 12th, 2024

The USTC realizes In situ electron paramagnetic resonance spectroscopy using single nanodiamond sensors November 3rd, 2023

Observation of left and right at nanoscale with optical force October 6th, 2023

Possible Futures

Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Nanomedicine

High-tech 'paint' could spare patients repeated surgeries March 8th, 2024

Researchers develop artificial building blocks of life March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Discoveries

What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024

Researchers’ approach may protect quantum computers from attacks March 8th, 2024

High-tech 'paint' could spare patients repeated surgeries March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Announcements

What heat can tell us about battery chemistry: using the Peltier effect to study lithium-ion cells March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters

Researchers develop artificial building blocks of life March 8th, 2024

How surface roughness influences the adhesion of soft materials: Research team discovers universal mechanism that leads to adhesion hysteresis in soft materials March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

Nanobiotechnology

High-tech 'paint' could spare patients repeated surgeries March 8th, 2024

Researchers develop artificial building blocks of life March 8th, 2024

Curcumin nanoemulsion is tested for treatment of intestinal inflammation: A formulation developed by Brazilian researchers proved effective in tests involving mice March 8th, 2024

The Access to Advanced Health Institute receives up to $12.7 million to develop novel nanoalum adjuvant formulation for better protection against tuberculosis and pandemic influenza March 8th, 2024

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project