Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Novel chip-based platform could simplify measurements of single molecules: A nanopore-gated optofluidic chip combines electrical and optical measurements of single molecules onto a single platform

The nanopore-gated optofluidic chip is able to distinguish influenza viruses from nanobeads.
The nanopore-gated optofluidic chip is able to distinguish influenza viruses from nanobeads.

Abstract:
Researchers at UC Santa Cruz have developed a new approach for studying single molecules and nanoparticles by combining electrical and optical measurements on an integrated chip-based platform. In a paper published July 9 in Nano Letters, the researchers reported using the device to distinguish viruses from similarly-sized nanoparticles with 100 percent fidelity.

Novel chip-based platform could simplify measurements of single molecules: A nanopore-gated optofluidic chip combines electrical and optical measurements of single molecules onto a single platform

Santa Cruz, CA | Posted on August 14th, 2014

Combining electrical and optical measurements on a single chip provides more information than either technique alone, said corresponding author Holger Schmidt, the Kapany Professor of Optoelectronics in the Baskin School of Engineering and director of the W. M. Keck Center for Nanoscale Optofluidics at UC Santa Cruz. Graduate student Shuo Liu is first author of the paper.

The new chip builds on previous work by Schmidt's lab and his collaborators at Brigham Young University to develop optofluidic chip technology for optical analysis of single molecules as they pass through a tiny fluid-filled channel on the chip. The new device incorporates a nanopore that serves two functions: it acts as a "smart gate" to control the delivery of individual molecules or nanoparticles into the channel for optical analysis; and it allows electrical measurements as a particle passes through the nanopore.

"The nanopore delivers a single molecule into the fluidic channel, where it is then available for optical measurements. This is a useful research tool for doing single-molecule studies," Schmidt said.

Biological nanopores, a technology developed by coauthor David Deamer and others at UC Santa Cruz, can be used to analyze a DNA strand as it passes through a tiny pore embedded in a membrane. Researchers apply voltage across the membrane, which pulls the negatively charged DNA through the pore. Current fluctuations as the DNA moves through the pore provide electrical signals that can be decoded to determine the genetic sequence of the strand.

With the new device, researchers are able to gather electrical measurements on a nanoparticle as it moves through a pore in a solid membrane, and then measure the optical signals when the particle encounters a beam of light in the channel. By correlating the strength of the current decrease as a particle moves through the pore, the intensity of the optical signal, and the time of each measurement, the researchers are able to discriminate among particles with different sizes and optical properties and to determine the flow speed of particles through the channel.

The chip can also be used to differentiate particles of similar size but different composition. In one experiment, the researchers combined influenza viruses with nanobeads of a similar diameter and placed the mixture above the nanopore. The virus was labeled with a red fluorescent tag and the beads were labeled with a blue tag. The researchers correlated the electrical signal with the fluorescent wavelength and the time of each measurement. They found that the blue nanobeads traveled faster through the channel than red influenza virus, perhaps because of a difference in surface charge or mass. Besides identifying pathogens in a mixture, the researchers can also count the number of virus particles.

"This could be used as an analytical device to do reliable counts of virus particles in a sample," Schmidt said.

Currently, Schmidt's group is working on methods to add optical trapping to the device. This would allow a molecule in the channel to be held in one place, investigated, and released, with the potential to analyze hundreds of molecules in an hour. "Having this all on one chip would make single-molecule measurements much easier and more convenient," Schmidt said.

###

In addition to Liu and Schmidt, the coauthors include UCSC graduate student Joshua Parks, and Yue Zhao and Aaron Hawkins at Brigham Young University. This work was supported by the Keck Center for Nanoscale Optofluidics and grants from the National Science Foundation and National Institutes of Health.

####

For more information, please click here

Contacts:
Tim Stephens

831-459-2495

Copyright © University of California - Santa Cruz

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 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

Microfluidics/Nanofluidics

Implantable device shrinks pancreatic tumors: Taming pancreatic cancer with intratumoral immunotherapy April 14th, 2023

Computational system streamlines the design of fluidic devices: This computational tool can generate an optimal design for a complex fluidic device such as a combustion engine or a hydraulic pump December 9th, 2022

Researchers design new inks for 3D-printable wearable bioelectronics: Potential uses include printing electronic tattoos for medical tracking applications August 19th, 2022

Oregon State University research pushes closer to new therapy for pancreatic cancer May 6th, 2022

Govt.-Legislation/Regulation/Funding/Policy

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

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

Optically trapped quantum droplets of light can bind together to form macroscopic complexes 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

Research partnerships

Researchers’ approach may protect quantum computers from attacks 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

'Sudden death' of quantum fluctuations defies current theories of superconductivity: Study challenges the conventional wisdom of superconducting quantum transitions January 12th, 2024

Development of zinc oxide nanopagoda array photoelectrode: photoelectrochemical water-splitting hydrogen production January 12th, 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