Chemical engineering’s film stars (Day 137)

London skyline

London’s evolving skyline

I was casting an eye over the evolving sky-scrape of London recently and marveled at some of the new architecture and buildings which have appeared like the Shard, the Gherkin and the Cheesegrater.

The UK is not renowned for its tall buildings, but the success of the UK’s capital and growing population (which is forecast to make it the most populous country in the European Union over the next few decades), has led to a bit of vertical thinking.

Of course, these buildings are the result of some fantastic engineering and there for everyone to enjoy – on a functional and aesthetic level.

One of the [minor] frustrations of being a chemical engineer is that not everything we do is so self-evident. In fact, some of us operate at levels no one can see, but our efforts influence some of our biggest man-made objects – and keep us safe.

One of those fields is chemical engineering’s very own ‘film stars’ or coatings.

The ability to repel liquids and contaminants has important practical applications to industry and everyday life.

Some coatings are used to help stop the formation of life-threatening bacteria on medical instruments, ice build-up on air planes, fouling on ship hulls, anti-corrosion and the efficient transportation of products like crude oil by pipeline.

One of the entrants at last year’s IChemE Global Awards – Harvard University – were a great example of the type of technology developed by chemical engineering.

Harvard were able to mimic the pitcher plant’s inner skin design to produce a transparent coating capable of being economically applied to almost any object – large or small.

Their multi-stage coating process involved attaching a thin, but rough layer of porous silica particles which were used to lock-in a lubricating layer onto the surface to be protected. Its diverse applications could include acting as an anti-graffiti coating on walls or on medical implants to aid blood flow.

Soldier's equipmentThere are other applications too – in unusual places. Soldiers in the field are constantly struggling to keep out dust, dirt and germs from their weapons, personal effects and even their own bodies.

Scientists in the US  are undertaking work to find a better way to cut down on bacterial biofouling to reduce the number of pathogens soldiers, sailors and airmen face.

One of the people involved in the project is Dr. Gabriel Lopez, professor of biomedical engineering from Duke University.

Gabriel has been involved in the successful demonstration of a newly developed methodology to deposit multi-functional films which have antimicrobial and fouling-release properties when exposed to light from a special laser.

During tests, the team were able to demonstrate, with good results, how the deposited films were characterised and tested against Escherichia coli K12 and Staphylococcus epidermidis.

Light activited killer films

Light-activated killer films. Image by Dr. Gabriel Lopez.

The film’s biocidal and bacterial-release ability was retained even after several attach-kill-release cycles.

These smart surfaces will potentially have field applications as devices for detecting, capturing, and destroying chem-bio warfare agents, acting to repeatedly capture and kill bacteria. They might also be useful for testing predictive models that evaluate bacterial agent adhesion on relevant surfaces.

Work like this may not be as visible as a skyscraper, but the engineering is just as impressive, with huge potential.

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Are you a chemical engineer that is working on a ‘behind the scenes’ project to protect or improve quality of life? Please tell us your story.