Tag Archives: Magic Molecule

Thoughts on part 4 of (PBS) Nova’s Making Stuff series

Last night (Feb.9.11) PBS aired the final part of the Making Stuff  series as part of its Nova tv programming. It was titled Making Stuff Smarter and did not feature a single bot of any kind or any nanoscale computers or labs on chips thereby frustrating (not in a bad way) some of my expectations but I should have become accustomed to that by now.

There was a focus on something called biomimicry, a term I did not hear used while I was watching (confession: I didn’t watch every single minute of the show), where researchers try to make materials that mimic a process or ability observed in nature. They used sharkskin as an example for making a ‘smarter’ material. Scientists have observed that nanoscale structures on a shark’s skin have antibacterial properties. This is especially important when we have a growing problem with bacteria that are antibiotic resistant. David Pogue’s (the program host) interviewed scientists at Sharklet and highlighted their work producing a plastic with nanostructures similar to those found on sharkskin for use in hospitals, restaurants, etc.  I found this on the Sharklet website (from a rotating graphic on the home page),

The World Health Organization calls antibiotic resistance a leading threat to human health.

Sharkjet provides a non-toxic approach to bacterial control and doesn’t create resistance.

The reason that the material does not create resistance is that it doesn’t kill the bacteria (antibiotics kill most bacteria but cannot kill all of them with the consequence that only the resistant survive and reproduce). Excerpted from Sharklet’s technology page,

While the Sharklet pattern holds great promise to improve the way humans co-exist with microorganisms, the pattern was developed far outside of a laboratory. In fact, Sharklet was discovered via a seemingly unrelated problem: how to keep algae from coating the hulls of submarines and ships. In 2002, Dr. Anthony Brennan, a materials science and engineering professor at the University of Florida, was visiting the U.S. naval base at Pearl Harbor in Oahu as part of Navy-sponsored research. The U.S. Office of Naval Research solicited Dr. Brennan to find new antifouling strategies to reduce use of toxic antifouling paints and trim costs associated with dry dock and drag.

Dr. Brennan was convinced that using an engineered topography could be a key to new antifouling technologies. Clarity struck as he and several colleagues watched an algae-coated nuclear submarine return to port. Dr. Brennan remarked that the submarine looked like a whale lumbering into the harbor. In turn, he asked which slow moving marine animals don’t foul. The only one? The shark.

Dr. Brennan was inspired to take an actual impression of shark skin, or more specifically, its dermal denticles. Examining the impression with scanning electron microscopy, Dr. Brennan confirmed his theory. Shark skin denticles are arranged in a distinct diamond pattern with tiny riblets. Dr. Brennan measured the ribs’ width-to-height ratios which corresponded to his mathematical model for roughness – one that would discourage microorganisms from settling. The first test of Sharklet yielded impressive results. Sharklet reduced green algae settlement by 85 percent compared to smooth surfaces.

There’s more to the story so I encourage you to take a look at the page. What I find compelling about biomimicry is that we are learning from nature and mimicking it rather than try to control or destroy what we view as dangerous to us or, in some cases, not valuable. Interestingly, this program featured the military quite prominently in other segments while, as far as I’m aware, failing to mention biomimcry  which suggests (I’m putting on my semiotic hat) that our ideas about controlling nature and using warlike metaphors to describe scientific and medical efforts are still dominant socially and being reproduced.

I enjoyed (with qualifications regarding some of the subtext) the program series (all three of the shows I managed to watch) but, as I’ve noted previously, I’m not the target market so some of it was a bit too fluffy for me.

I found this fourth installment the most interesting and I was delighted to see that they featured climbing robots (based on geckos and mentioned in my Aug. 2, 2010 posting) and invisibility (mentioned most recently in my Jan. 26, 2011 posting although that features a different approach than the one mentioned in the program) along with a few items that were new to me.

Coincidentally the National Film Board of Canada is featuring a film short titled, Magic Molecule in its Feb. 9, 2011 newsletter. Produced in 1964, it introduces us to the fabulous world of plastics. In some ways, it’s very similar to the Making Stuff series. The tone is upbeat and very much pro plastics and its wonders.