Only over the past 20 years have we begun to harness the unique properties of nano-scale materials, while nature has been using nano- “technology” since the beginning of time to prevent infections, repel water, create colors, and climb vertical surfaces. Inspired by nature’s advances, scientists and engineers are generating biomimetic applications for nanotechnology in today’s world.
Shark Skin: The power of anti-bacterial invincibility
Sharks have been swimming in the oceans for millions of years without the problematic accumulation of algae and bacteria on the surface of their skin. This is because the nano-scale patterns on the shark’s skin deflect the accumulation of barnacles, algae, and bacteria (Figure 1). Algae and bacteria tend to settle on surfaces and ultimately establish colonies and biofilms. It is easier to colonize a smooth surface, whereas establishing a biofilm over a rough surface requires too much energy for colonization and makes signaling between cells in the colony difficult. Surfaces that prevent the underwater growth of bacteria, algae, and organisms are known as anti-fouling. These surfaces are essential for maintaining functional pipelines, ships, submarines, and other submerged infrastructures and technologies. Until now, anti-fouling techniques have primarily involved coating surfaces with chemicals that can be toxic to humans and the environment, in addition to their bacterial and algal targets. To avoid these problems, scientists and engineers have begun to integrate this anti-bacterial nano-scale pattern onto high-traffic surfaces. Sharklet Technologies Inc. has incorporated this pattern onto railings and door handles in airports and hospitals and also on medical equipment to reduce bacterial colonization.
Figure 1. Nano-scale patterns on shark skin help prevent bacteria and algal growth
Image adapted from: Source1 Source2
Take a look at your wrist. Have you ever wonder what makes your watch tick with such precision? What if I told you the same technology that causes your watch to work is also key to one of the most sensitive balances on the planet? Sounds crazy right?!
Well, I promise it’s not crazy! The answer to both lies in the properties of quartz. Quartz is a mineral that you can find in granite and sandstone, and you may even have some jewelry containing this gemstone. What makes quartz so beneficial is the fact that it produces an electrical current when it is squeezed. The reverse is also true, meaning that if we apply a voltage to quartz it will deform or move back and forth in response to this (electrical) stress. Quartz and other materials that exhibit this property are known as piezoelectric materials. (Languate note: the roots of the word piezoelectric come from the Greek word piezin meaning to press or squeeze)
The University of Minnesota’s Office for Equity and Diversity awarded Kadir Hussein with their Scholarly Excellence in Equity and Diversity (SEED) Award. Kadir is an undergraduate student who does research as part of the Center for Sustainable Nanotechnology under the guidance of Professor Christy Haynes at the University of Minnesota. He participated in our Research Experiences for Undergraduates program this past summer and was a pleasure to work with. The SEED award that he received “honors and acknowledges diverse students who are doing outstanding work at the University of Minnesota, both in and out of the classroom.”
In addition to doing excellent scientific work with our research center, he is president of the Oromia Student Union (Oromia, Ethiopia is where Kadir was originally from) and president of the University of Minnesota’s chapter of the National Organization for the Professional Advancement of Black Chemists and Chemical Engineers. As if this didn’t keep him busy enough, Kadir also serves as a peer mentor for the North Star STEM Alliance Program and Huntley House for African American Men, a living-learning community that aims to “build community by exploring the shared experience of African American males in and out of the classroom.”
When does he sleep?! Congratulations Kadir!
An acronym you have probably seen a whole lot of in recent years is LED, or Light Emitting Diode. Long used only for low-intensity illumination (think of the blinking lights on the front of your computer), the new generations of LEDs are being used to replace all sorts of light sources from car head lights to flat panel televisions to the common light bulb. Compared to old style incandescent (or filament) bulbs and even the new compact fluorescent bulbs, LEDs use much less energy to generate the same amount of light and last longer than both other types of bulb.
LED bulbs of three different colors. Thanks to advances in LED technology, more powerful bulbs are being manufactured. Image source
This post is written by Anna Bisaro and originally appeared on Medill Reports, a project of Northwestern University graduate journalism students.
Sustainability. The magic word that rings with the promises of a better world and cost savings. People want to create clean energy, recycle wastes and eat locally-grown food, all in the quest for sustainability.
But what about the nanoparticles people cannot see which are growing in popularity in industry, agriculture and all along the path to sustainability and innovation?
Nanoparticles are designer molecules that can customize just about any product as used today in cancer treatments, medical diagnostics, batteries, solar cells and even sunscreen. But, the potential effects of these particles on living things, as well as on the environment, remain unknown. Preliminary research by the Center for Sustainable Nanotechnology lab at Northwestern University is finding that nanoparticles could affect cellular membranes.
An illustration of what the lipid bilayers, representative of cellular membranes, look like in a constructed cell, supported by silica. Northwetern researchers are looking at how gold nanoparticles interact with cells.
“There are many compounds in the environment where we know they are not environmentally benign,” said Northwestern chemistry professor Franz Geiger. We found out too late about the dangers associated with asbestos and chlorofluorocarbons. “Was that predictable?” he said. Continue reading on Medill Reports.
The idea that an image is worth a thousand words applies just as much in science as it does in other contexts. Using images, scientists can convey complex information more quickly and often more clearly than is possible using words—which do you prefer: words (left) or a picture (right)?
Today I want to talk about how we in the Center for Sustainable Nanotechnology zoom in on the nanoworld; specifically, how we see living things, like cells, interacting with nanomaterials. We care about this because we think that nanomaterials, given their incredibly small size, may interact with living things in strange ways. But if we want to see this interaction, we’ll first need to come up with some way to see things on the nanoscale. It turns out that this is no easy task, which may not surprise you. But why exactly is it so hard to see small things like nanomaterials and cells? And how can we overcome these difficulties? Continue reading
Adventures In the Nano Zone! That is the title of the internet presentation that scientists from the Center for Sustainable Nanotechnology gave last Friday to 8th graders at the Hewitt School, an all-girls school in New York City. That was followed by lively Q&A sessions. During this week, Hewitt School students will be asking Center scientists more questions via comments at the end of this blog post, so stay tuned!
Some screenshots of students from the webinar introduction
Here’s the deal. Hewitt School teacher, Kristina Walter, had a section on nanotechnology planned for her students and also happened to see a link on Facebook to one of our blog posts. Crazy! Together, we came up with a little experiment. Last Friday’s “webinar” was an introduction to nanotechnology and the goals of our research center. As the students come up with projects related to nanotechnology, they will get some help from Center scientists via a Q&A in the comments section of this blog post. In another post, we will publish a sampling of some of the student projects. We’re happy we could help out and are super excited to see what the students come up with!
Yay internets! Yay science!
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