Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > UCSB Scientists Demonstrate Biomagnification of Nanomaterials in Simple Food Chain

The quantum dot-tainted bacteria stop digestion in the protozoan, and food vacuoles with undigested material accumulate, seen in the right image. This is in contrast to the normal condition of protozoa eating untreated bacteria, seen in the left image.
The quantum dot-tainted bacteria stop digestion in the protozoan, and food vacuoles with undigested material accumulate, seen in the right image. This is in contrast to the normal condition of protozoa eating untreated bacteria, seen in the left image.

Abstract:
An interdisciplinary team of researchers at UC Santa Barbara has produced a groundbreaking study of how nanoparticles are able to biomagnify in a simple microbial food chain.

UCSB Scientists Demonstrate Biomagnification of Nanomaterials in Simple Food Chain

Santa Barbara, CA | Posted on December 20th, 2010

"This was a simple scientific curiosity," said Patricia Holden, professor in UCSB's Bren School of Environmental Science & Management and the corresponding author of the study, published in an early online edition of the journal Nature Nanotechnology. "But it is also of great importance to this new field of looking at the interface of nanotechnology and the environment."

Holden's co-authors from UCSB include Eduardo Orias, research professor of genomics with the Department of Molecular, Cellular and Developmental Biology; Galen Stucky, professor of chemistry and biochemistry, and materials; and graduate students, postdoctoral scholars, and staff researchers Rebecca Werlin, Randy Mielke, John Priester, and Peter Stoimenov. Other co-authors are Stephan Krämer, from the California Nanosystems Institute, and Gary Cherr and Susan Jackson, from the UC Davis Bodega Marine Laboratory.

The research was partially funded by the U.S. Environmental Protection Agency (EPA) STAR Program, and by the UC Center for the Environmental Implications of Nanotechnology (UC CEIN), a $24 million collaboration based at UCLA, with researchers from UCSB, UC Davis, UC Riverside, Columbia
University, and other national and international partners. UC CEIN is funded by the National Science Foundation and the EPA.

According to Holden, a prior collaboration with Stucky, Stoimenov, Priester, and Mielke provided the foundation for this research. In that earlier study, the researchers observed that nanoparticles formed from cadmium selenide were entering certain bacteria (called Pseudomonas) and accumulating in them. "We already knew that the bacteria were internalizing these nanoparticles from our previous study," Holden said. "And we also knew that Ed (Orias) and Rebecca (Werlin) were working with a protozoan called Tetrahymena and nanoparticles. So we approached them and asked if they would be interested in a collaboration to evaluate how the protozoan predator is affected by the accumulated nanoparticles inside a bacterial prey." Orias and Werlin credit their interest in nanoparticle toxicity to earlier funding from and participation in the University of California
Toxic Substance Research & Training Program.

The scientists repeated the growth of the bacteria with quantum dots in the new study and and coupled it to a trophic transfer study - the study of the transfer of a compound from a lower to a higher level in a food chain by predation. "We looked at the difference to the predator as it was growing at the expense of different prey types - 'control' prey without any metals, prey that had been grown with a dissolved cadmium salt, and prey that had been grown with cadmium selenide quantum dots," Holden said.

What they found was that the concentration of cadmium increased in the transfer from bacteria to protozoa and, in the process of increasing concentration, the nanoparticles were substantially intact, with very little degradation. "We were able to measure the ratio of the cadmium to the selenium in particles that were inside the protozoa and see that it was substantially the same as in the original nanoparticles that had been used to feed the bacteria," Orias said.

The fact that the ratio of cadmium and selenide was preserved throughout the course of the study indicates that the nanoparticles were themselves biomagnified. "Biomagnification - the increase in concentration of cadmium as the tracer for nanoparticles from prey into predator - this is the first time this has been reported for nanomaterials in an aquatic environment, and furthermore involving microscopic life forms, which comprise the base of all food webs," Holden said.

An implication is that nanoparticles inside the protozoa could then be available to the next level of predators in the food chain, which could lead to broader ecological effects. "These protozoa are greatly enriched in nanoparticles because of feeding on quantum dot-laced bacteria," Hold said. "Because there were toxic effects on the protozoa in this study, there is a concern that there could also be toxic effects higher in the food chain, especially in aquatic environments."

One of the missions of UC CEIN is to try to understand the effects of nanomaterials in the environment, and how scientists can prevent any possible negative effects that might pose a threat to any form of life. "In this context, one might argue that if you could 'design out' whatever property of the quantum dots causes them to enter bacteria, then we could avoid this potential consequence," Holden said. "That would be a positive way of viewing a study like this. Now scientists can look back and say, 'How do we prevent this from happening?'"

####

For more information, please click here

Contacts:
George Foulsham
(805) 893-3071


Patricia Holden
(805) 893-3195


Eduardo Orias
(805) 893-3024

Copyright © UCSB

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

Thin films offer promise for ferroelectric devices: Researchers at Tokyo Institute of Technology demystify the ferroelectric properties observed in hafnium-oxide-based thin films, revealing a potentially useful device material August 3rd, 2015

Harris & Harris Group Portfolio Company, HZO, Announces Partnerships with Dell and Motorola August 1st, 2015

Advances and Applications in Biosensing, Sensor Power, and Sensor R&D to be Covered at Sensors Global Summit August 1st, 2015

Kalam: versatility personified August 1st, 2015

Marine/Watercraft

Controlling Dynamic Behavior of Carbon Nanosheets in Structures Made Possible July 30th, 2015

Enhanced Graphene Components for Next Generation Racing Yacht March 5th, 2015

BRAAVOO will design an unmanned surveying vessel and marine buoy that carry biosensors to monitor marine pollutants November 12th, 2014

First Observation of Electronic Structure in Ag-Rh Alloy Nanoparticles Having Hydrogen Absorbing: Storage Property –Attempting to solve the mystery of why Ag-Rh alloy nanoparticles have a similar property to Pd– October 30th, 2014

Preparing for Nano

Durnham University's DEEPEN project comes to a close September 26th, 2012

Technical Seminar at ANFoS 2012 August 22nd, 2012

Nanotechnology shows we can innovate without economic growth April 12th, 2012

Thailand to host NanoThailand 2012 December 18th, 2011

Govt.-Legislation/Regulation/Funding/Policy

Self-assembling, biomimetic membranes may aid water filtration August 1st, 2015

Kalam: versatility personified August 1st, 2015

Heating and cooling with light leads to ultrafast DNA diagnostics July 31st, 2015

Theoretical Physicists at Freie Universität Berlin Develop New Insights into Interface between Classical and Quantum Worlds July 31st, 2015

Academic/Education

Pakistani Students Who Survived Terror Attack to Attend Weeklong “NanoDiscovery Institute” at SUNY Poly CNSE in Albany July 29th, 2015

Deben reports on the use of their CT500 in the X-ray microtomography laboratory at La Trobe University, Melbourne, Australia July 22nd, 2015

JPK reports on the use of SPM in the Messersmith Group at UC Berkeley looking at biologically inspired polymer adhesives. July 21st, 2015

Renishaw adds Raman analysis to Scanning Electron Microscopy at the University of Sydney, Australia July 9th, 2015

Materials/Metamaterials

Thin films offer promise for ferroelectric devices: Researchers at Tokyo Institute of Technology demystify the ferroelectric properties observed in hafnium-oxide-based thin films, revealing a potentially useful device material August 3rd, 2015

Shaping the hilly landscapes of a semi-conductor nanoworld August 1st, 2015

Self-assembling, biomimetic membranes may aid water filtration August 1st, 2015

Transparent, electrically conductive network of encapsulated silver nanowires: A novel electrode for optoelectronics August 1st, 2015

Announcements

Thin films offer promise for ferroelectric devices: Researchers at Tokyo Institute of Technology demystify the ferroelectric properties observed in hafnium-oxide-based thin films, revealing a potentially useful device material August 3rd, 2015

Transparent, electrically conductive network of encapsulated silver nanowires: A novel electrode for optoelectronics August 1st, 2015

Harris & Harris Group Portfolio Company, HZO, Announces Partnerships with Dell and Motorola August 1st, 2015

Advances and Applications in Biosensing, Sensor Power, and Sensor R&D to be Covered at Sensors Global Summit August 1st, 2015

Environment

March 2016; 6th Int'l Conference on Nanostructures in Iran July 29th, 2015

Laboratorial Performance of Nanocomposite Membrane Improved in Water Purification July 28th, 2015

Nanosorbents Reduce Amount of Heavy Metals in Petrochemical Wastewater July 23rd, 2015

Nanopaper as an optical sensing platform July 23rd, 2015

Safety-Nanoparticles/Risk management

March 2016; 6th Int'l Conference on Nanostructures in Iran July 29th, 2015

Environmentally friendly lignin nanoparticle 'greens' silver nanobullet to battle bacteria July 13th, 2015

NIST ‘How-To’ Website Documents Procedures for Nano-EHS Research and Testing July 1st, 2015

Proposed TSCA Nanomaterial Rule ‘Premature’, Says Former EPA Toxicologist July 1st, 2015

Quantum Dots/Rods

Quantum networks: Back and forth are not equal distances! July 28th, 2015

Superfast fluorescence sets new speed record: Plasmonic device has speed and efficiency to serve optical computers July 27th, 2015

Engineered hybrid crystal opens new frontiers for high-efficiency lighting: University of Toronto researchers successfully combine 2 different materials to create new hyper-efficient light-emitting crystal July 16th, 2015

Down to the quantum dot: Jülich researchers develop ultrahigh-resolution 3-D microscopy technique for electric fields July 7th, 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