Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > NRL Scientists Unravel Complex Quantum Dot-Dopamine Interactions

Intracellular pH sensing. Fluorescent micrographs collected from COS-1 cells co-injected with 550 nm emitting QD-dopamine conjugates and red FLX internal standard nanospheres in buffer at pH 6.5. The growth media was switched to pH 11.5 supplemented with the drug Nystatin and micrographs were captured at the indicated time intervals from both the QD and FLX emission channels. Merged images are shown in the bottom row and pH values extracted at each time interval are shown below.
Intracellular pH sensing. Fluorescent micrographs collected from COS-1 cells co-injected with 550 nm emitting QD-dopamine conjugates and red FLX internal standard nanospheres in buffer at pH 6.5. The growth media was switched to pH 11.5 supplemented with the drug Nystatin and micrographs were captured at the indicated time intervals from both the QD and FLX emission channels. Merged images are shown in the bottom row and pH values extracted at each time interval are shown below.

Abstract:
Scientists at the Naval Research Laboratory in conjunction with the Scripps Research Institute in La Jolla, Ca., recently reported a detailed study of the interactions of water soluble semi-conductor quantum dots (QDs) with the electro-active neuro-transmitter dopamine. These biocompatible QD-dopamine nano-assemblies may be used as the active component for sensors that are used to detect a wide variety of target analytes ranging from sugars to peroxides.

NRL Scientists Unravel Complex Quantum Dot-Dopamine Interactions

Washington, DC | Posted on October 18th, 2010

According to NRL's Dr. Michael Stewart, a member of the research team "The nature of the QD-dopamine interaction has been the subject of more than 25 recent research papers that attempted to uncover and exploit the exact nature of how the QDs interact with these small electro-active chemicals during the sensing process. Until now, it remained unclear as to whether dopamine acted as an electron acceptor or as an electron donor to quench luminescence from the QD."

"The chemical state of dopamine changes from a protonated hydroquinone in acidic media to an oxidized quinone in basic environments. A series of carefully designed experiments allowed the research team to establish that only the quinone form is capable of acting as an electron acceptor resulting in quenching of the QD emission. The rate of quinone formation and hence QD quenching is directly proportional to pH and can therefore be used to detect changes in the pH of solutions. Using this nano-scale sensor, the research team was able to demonstrate pH sensing in solution and even visualize changes inside cells as cell cultures underwent drug-induced alkalosis," explained Dr. Scott Trammell.

The interdisciplinary group of scientists involved in this project from NRL include: Dr. Michael Stewart and Dr. Kimihiro Susumu of NRL's Optical Sciences Division, and Dr. Igor Medintz, Dr. Scott Trammell, and Dr. James Delehanty from NRL's Center for Bio/Molecular Science and Engineering, along with Professor Phillip Dawson and Dr. Juan B. Blanco-Canosa of the Scripps Research Institute.

This research was supported by NRL's Nanoscience Institute and the Defense Threat Reduction Agency (DTRA), and is focused on areas tasked to the Department of Defense under the President's National Nanotechnology Initiative. The research was published in the August 2010 issue of Nature Materials.

####

For more information, please click here

Contacts:
Dom Panciarelli
(202) 767-2541

Copyright © Naval Research Laboratory

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

New Hopes for Treatment of Intestine Cancer by Edible Nanodrug March 2nd, 2015

Imec, Holst Centre and Renesas Present World’s Lowest Power 2.4GHz Radio Chip for Bluetooth Low Energy March 1st, 2015

Imec, Murata, and Huawei Introduce Breakthrough Solution for TX-to-RX Isolation in Reconfigurable, Multiband Front-End Modules for Mobile Phones: Electrical-Balance Duplexers Pave the Way to Integrated Solution for TX-to-RX Isolation March 1st, 2015

Imec Demonstrates Compact Wavelength-Division Multiplexing CMOS Silicon Photonics Transceiver March 1st, 2015

Govt.-Legislation/Regulation/Funding/Policy

First detailed microscopy evidence of bacteria at the lower size limit of life: Berkeley Lab research provides comprehensive description of ultra-small bacteria February 28th, 2015

Warming up the world of superconductors: Clusters of aluminum metal atoms become superconductive at surprisingly high temperatures February 25th, 2015

SUNY Poly CNSE Researchers and Corporate Partners to Present Forty Papers at Globally Recognized Lithography Conference: SUNY Poly CNSE Research Group Awarded Both ‘Best Research Paper’ and ‘Best Research Poster’ at SPIE Advanced Lithography 2015 forum February 25th, 2015

European roadmap for graphene science and technology published February 25th, 2015

Sensors

Penn researchers develop new technique for making molybdenum disulfide: Extra control over monolayer material with advantages over graphene February 19th, 2015

Researchers build atomically thin gas and chemical sensors: Sensors made of molybdenum disulfide are small, thin and have a high level of selectivity when detecting gases and chemicals February 19th, 2015

Production of Biosensor in Iran to Detect Oxalic Acid February 18th, 2015

Improved fire detection with new ultra-sensitive, ultraviolet light sensor February 17th, 2015

Announcements

New Hopes for Treatment of Intestine Cancer by Edible Nanodrug March 2nd, 2015

Imec Demonstrates Compact Wavelength-Division Multiplexing CMOS Silicon Photonics Transceiver March 1st, 2015

onic Present breakthrough in CMOS-based Transceivers for mm-Wave Radar Systems March 1st, 2015

Graphene Shows Promise In Eradication Of Stem Cancer Cells March 1st, 2015

Military

Simulating superconducting materials with ultracold atoms: Rice physicists build superconductor analog, observe antiferromagnetic order February 23rd, 2015

Perfect colors, captured with one ultra-thin lens: No need for color correction -- Harvard physicists' flat optics, using nanotechnology, get it right the first time February 19th, 2015

Penn researchers develop new technique for making molybdenum disulfide: Extra control over monolayer material with advantages over graphene February 19th, 2015

New nanogel for drug delivery: Self-healing gel can be injected into the body and act as a long-term drug depot February 19th, 2015

Quantum Dots/Rods

Optical nanoantennas set the stage for a NEMS lab-on-a-chip revolution February 24th, 2015

QD Vision Named Edison Award Finalist for Innovative Color IQ™ Quantum Dot Technology February 23rd, 2015

Ocean Optics Names Winner of 2015 Young Investigator Award: Cash prize and grant awarded during SPIE BiOS/Photonics West 2015 conference February 21st, 2015

Rediscovering spontaneous light emission: Berkeley researchers develop optical antenna for LEDs February 3rd, 2015

Nanobiotechnology

Untangling DNA with a droplet of water, a pipet and a polymer: With the 'rolling droplet technique,' a DNA-injected water droplet rolls like a ball over a platelet, sticking the DNA to the plate surface February 27th, 2015

Bacteria network for food: Bacteria connect to each other and exchange nutrients February 23rd, 2015

Building tailor-made DNA nanotubes step by step: New, block-by-block assembly method could pave way for applications in opto-electronics, drug delivery February 23rd, 2015

Better batteries inspired by lowly snail shells: Biological molecules can latch onto nanoscale components and lock them into position to make high performing Li-ion battery electrodes, according to new research presented at the 59th annual meeting of the Biophysical Society February 12th, 2015

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




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE