Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Introduction to nanotechnology and its ecological implications

Introduction to nano for high school students

Xueying Han

on 9 November 2014

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Introduction to nanotechnology and its ecological implications

Why do properties depend on size?


Specialized instrumentation
Transmission electron microscope (TEM)
Scanning electron microscope (SEM)
Atomic force microscope (AFM)
Physical knowledge and intuition

Can we control the nanoscale?
Nanotechnology and Its Ecological Implications

Shirley Han, Ph.D.
Louise Stevenson, Ph.D. Candidate
Center for Nanotechnology in Society
University of California at Santa Barbara

19 May 2014


Environmental sciences
Future of nanotechnology
Warm up question
Should silver (a known
compound used in many consumer products to kill bacteria) be regulated by the Environmental Protection Agency the same way regardless of its size?

Learning objectives
1) Students will learn what
is, what it's used for, and why it's important

2) Students will learn about how
is regulated

3) Students will learn about experiments scientists are doing to estimate the effect of
on the environment when they
from consumer products through the example of the effect of silver nanoparticles on freshwater algae
Nanotechnology Applications of the Future
Invisibility Cloaks??
1. Aren’t taking up nutrients
Algal cells in late stages of growth:

Ionic silver is toxic to aquatic systems
Second in toxicity only to mercury
Ingredient in commercial algicides
Ag is regulated by the EPA at nanomolar levels in aquatic environment

Silver in aquatic environments

Wound dressings
Food processing surfaces
Potential for environmental contamination
Leaching from consumer products
One of most commonly used
Silver nanoparticles
40 nm silver nanoparticles
Chlamydomonas reinhardtii
Freshwater green algae
Batch culture

Experimental system
Algal defense against the dark arts
Effect of silver nanoparticles on lakes and streams:
Daphnia and algal populations can cycle dramatically

Algal-produced organic material protecting other freshwater species

Organic material mitigation of Ag toxicity
3 different stages of growth

Experimental design
2. More organic material (dissolved organic carbon) produced by algae

Organic material mitigation of Ag toxicity
Organic material mitigation of Ag toxicity
What is Nanotechnology?
Nanotechnology in current day products
Organic material removal
restores toxicity
Stevenson LM, Dickson H, Klanjscek T, Keller AA, McCauley E, et al. (2013)
Environmental Feedbacks and Engineered Nanoparticles: Mitigation of Silver Nanoparticle Toxicity to Chlamydomonas reinhardtii by Algal-Produced Organic Compounds. PLoS ONE 8(9): e74456. doi: 10.1371/journal.pone.0074456
Full transcript