Navigation Links
Novel chip-based platform could simplify measurements of single molecules
Date:8/14/2014

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.

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.


'/>"/>

Contact: Tim Stephens
stephens@ucsc.edu
831-459-2495
University of California - Santa Cruz
Source:Eurekalert

Related biology technology :

1. Synthetic Biologics Academic Collaborator to Present Novel Monoclonal Antibody Combination for Treatment of Whooping Cough (Pertussis) at 54th ICAAC
2. Diagenode Launches Novel CRISPR/Cas9 Monoclonal Antibody
3. Harnessing Novel Techniques to Beat Dreadful Diabetes
4. University of Illinois researchers demonstrate novel, tunable nanoantennas
5. Novel Ms Techniques Speed Detection of Biopharmaceutical Product and Process Impurities, New Webinar Hosted by Xtalks
6. Global Record Systems Announces Research Collaboration Agreement with FDA to Create a Novel “Big Data” Paradigm for Collection of Patient Safety and Outcomes Information
7. Sequenom Announces Issuance Of European Patent For Novel Methods Of Detecting Fetal Aneuploidy
8. Data Highlights BGB324 as a Potential Novel Treatment Option for Drug Resistant Chronic Myeloid Leukemia
9. NKT Therapeutics Identifies Novel anti-iNKT Antibodies for Depleting or Activating iNKT Cells
10. Phase 2a Findings Demonstrate that CSL112, A Novel Apolipoprotein A-I Infusion Therapy, Has a Favorable Safety Profile, is Well Tolerated and Increases Cholesterol Efflux Capacity in Stable Atherothrombotic Patients
11. SignalRX Pharmaceuticals Issued U.S. Patent Covering Novel Kinase Inhibitors For Treating Cancer and Other Diseases
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/27/2016)... PUNE, India , April 27, 2016 /PRNewswire/ ... cytometry market research report with specific focus on ... Japan , to the healthcare ... and research library. Complete report on ... profiling 11 companies and supported with 282 tables ...
(Date:4/26/2016)... ... 26, 2016 , ... BaseHealth , the comprehensive predictive ... as Chief Business Officer. Arianpour, a genomics pioneer and visionary commercial leader with ... recently Chief Commercial Officer of Pathway Genomics. He has held senior executive roles ...
(Date:4/26/2016)... ... April 26, 2016 , ... Heidelberg Instruments, a leader ... innovation for its Volume Pattern Generator (VPG) line of lithography systems. The breakthrough ... as well as a solution for mid volume direct write lithography applications. ...
(Date:4/26/2016)... MA (PRWEB) , ... April 26, 2016 , ... This ... Town Scottsdale and will offer attendees an opportunity to get the lowdown on female ... , Over cocktails and appetizers, Dr. Jesse Hade, of Boston IVF - The Arizona ...
Breaking Biology Technology:
(Date:3/15/2016)... -- --> --> According ... "Digital Door Lock Systems Market - Global Industry Analysis, Size, ... digital door lock systems market in terms of revenue was ... to grow at a CAGR of 31.8% during the period ... (MSMEs) across the world and high industrial activity driving inclusive ...
(Date:3/14/2016)... , Allemagne, March 14, 2016 ... ) - --> - Renvoi : image ... --> --> ... biométriques, fournit de nouveaux lecteurs d,empreintes digitales pour ... de DERMALOG sera utilisé pour produire des cartes ...
(Date:3/10/2016)... --> --> ... and Access Management Market by Component (Provisioning, Directory Services, ... Organization Size, by Deployment, by Vertical, and by Region ... market is estimated to grow from USD 7.20 Billion ... a Compound Annual Growth Rate (CAGR) of 12.2% during ...
Breaking Biology News(10 mins):