Inventions for a Better Life

04.15.2014 | Science, Research, Faculty

(Cover photos used under Creative Commons from Abi Skipp Flickr photostream)

Two discoveries in University of Dayton laboratories recently received patents, paving the way for use in medical treatments that — among other applications — could make antibiotics 1,000 times more effective.

Jayne Robinson, biology professor and department chair, developed a unique method of applying an organic compound known as a porphyrin to break up and prevent the formation of bacterial biofilms, more commonly known as slime.

Proving the adage that there is strength in numbers, bacteria multiply and thrive by forming colonies. These colonies produce a sticky, slimy biofilm that acts as a barrier to predators, Robinson said.

This biofilm is also one of the primary defenses bacteria have against antibiotics. Eliminate the biofilm and antibiotics become more effective, in some cases up to 1,000 times more effective, Robinson said.

The compound could easily be applied using a spray or gel and could be used in medical facilities or at home, Robinson said.

"It's showing itself to be non-toxic in laboratory tests and much safer than bleach," she said. "Used in combination with an antibiotic, these compounds could effectively sterilize surgical instruments and implants, protect burn patients from infection and improve the fight against infections anywhere they occur."

And that's the truly innovative feature of Robinson's discovery: the porphyrin compound works even in the dark.

Scientists have known for years that porphyrins strongly absorb light and convert it to energy that generates compounds toxic to bacteria. Using porphyrins to kill bacteria is not new, but using it to break up biofilms and enhance antibiotic effectiveness without light is.

With Robinson's new method of preparing and applying the porphyrin compounds, the biofilm destruction can now be delivered to infections deep within tissues where this type of therapy has failed. It could also have non-medical applications, such as breaking up bacterial biofilms inside fuel lines, improving fuel efficiency.

The patent, U.S. Patent #8551456, was awarded to Robinson and Tracy Collins, now a post-doctoral fellow at Wright State University who earned her Ph.D. under Robinson at the University of Dayton.

A 'bio-inspired' ceramic

Ceramic materials are strong, non-toxic and have a variety of uses in medicine, construction and manufacturing. Ceramic coatings in particular are useful in strengthening biomedical implants and improving tissue adhesion.

However, the manufacturing process for ceramic coatings poses considerable risk to the environment. Requiring high temperature, high pressure and chemical solvents, the process consumes a large amount of fossil fuel and produces greenhouse gas emissions, while the solvents must be transferred, stored and disposed of.

University of Dayton biology assistant professor Karolyn Hansen believes there is a more effective and more environmentally friendly alternative to ceramic coatings, and it's something humans have been fascinated with for centuries: oyster shells.

The oyster's hard, outer shell is slowly and continuously constructed throughout its life. The beautiful and shiny inside of the shell is produced by a specialized tissue known as the mantle, and is responsible for shell creation. It lays down alternating layers of organic material and mineral material as it builds out the shell.

By depositing cells extracted from the mantle of an oyster onto a surface, Hansen and her team were able to successfully induce the creation of oyster shell layers as a coating.

This "bio-inspired," oyster-derived material is a strong, natural ceramic and can be manufactured at room temperature and pressure with no chemical solvents, Hansen said.

"It has numerous benefits," she said. "It's a step toward development of environmentally-friendly coatings that are mechanically tough and resistant to fracture. Potential applications include corrosion-resistant coatings and improved coatings for metallic biomedical implants." 

The process of building alternating layers also creates microscopic dips and cracks that provide more surface area for tissue to adhere, improving the biocompatibility of implants. 

This unique process of extracting and depositing oyster cells and inducing shell layering on a surface received U.S. Patent #8541031. In addition to Hansen, the inventors include Douglas Hansen of the University of Dayton Research Institute; and Andrew Mount, Neeraj Gohad and MaryBeth Johnstone of Clemson University.

For more information, contact Cameron Fullam, assistant director of media relations, at 937-229-3256 or fullam@udayton.edu.