From Cancer to Coatings and Cleanups  

Graduate students James Sullivan and Karpagavalli Ramji work with Professor Sergiu Gorun on their patent for self-cleaning protective coatings.

Professor Sergiu M. Gorun of the Department of Chemistry and Biochemistry and graduate students Karpagavalli Ramji and James Sullivan are the co-inventors of a patent for "Self-cleaning Protective Coatings." These protective coatings, sometimes referred to as "smart paint," actively repel contaminants and, as a result, may protect underlying surfaces better, longer and more completely than other paints.

Professor Gorun, who is the Director of the Center for Functional Materials at Seton Hall, in collaboration with colleagues and students, has also applied the underlying technology in the patent - harnessing the power of light through fluorinated photosensitizers (fluorinated phthalocyanine) - to act as an agent of eradication in the fight against cancer, with promising results.

Video: "Fighting Cancer with Light."

With Karpagavalli Ramji, a doctoral student at Seton Hall, Professor Gorun has worked on applying the same technology (with research assistance from undergraduate student, Christopher Colomier) to eliminate polluting contaminants from water. This research was funded in part by the United States Army, and Ramji's work on the project has won her the prestigious 2016 John J. LaGrosa Award from the New Jersey Water Environment Association, to be presented at its 101st Annual LaGrosa Conference and Exposition in May.

The use of this underlying research and technology to create "self-cleaning protective coatings," or "smart paint," that resulted in the patent co-authored by Ramji, Sullivan and Professor Gorun, was funded in part by the United States Air Force, which supported the research to help better safeguard its many resources from corrosion.

Corrosion is a major issue, and the world-wide market for protective coatings is big business. According to the World Paint & Coatings Industry Association, total global sales for paint and industrial coatings exceeded $128 billion in 2015. The economic impact for protective coatings, however, is far greater- as the cost of materials is normally calculated at approximately one fourth of the cost of coating, bringing the total global economic impact for paint and industrial coatings to over $500 billion in 2015 alone. And that doesn't count "down time," the period of time that a storage tank or a pipeline or some other metallic asset needs to be repainted and may not be used because rust, corrosion or contaminants have begun to threaten the integrity of the underlying surface.

And that's where Professor Gorun and his students come in. By introducing their technology into paint, they are able to repel not only water (as is the case with other commercial paints that inhibit rust) but also potentially a wide array of other contaminants and pollutants as well.

For the Air Force, corrosive pollutants are a major, and costly, issue. Bases steadily hum with the sound of diesel supply trucks and the roar of jet engines. Exhaust eats paint- and metal. With a commanding presence in hundreds of bases across the globe, and trillions of dollars in equipment, the Air Force needs paint that repels pollutants and other contaminants and extends the useful life of its materiel; thus far, the Air Force has contributed in excess of $500,000 toward Professor Gorun's research, which has also been advanced by Porter Scientific, a North Carolina contracting, consulting and service company, as well as the computational work from Professor Stephen Kelty at Seton Hall.

The Basis Research
Think of a solar panel: it captures light and produces electrons (i.e., electricity). Now think of that solar panel as being microscopically small, and instead of producing electrons, when activated by light in its proximity, "the fluoro panel" (fluorinated photosensitizer) takes the oxygen from its environment and transforms it into activated or "singlet" oxygen which, like a tiny ray gun, "shoots" and destroys carbon-based forms in its pathway.

This technology existed in part before Professor Gorun's discovery. But, prior to his research, like a honey bee that stings once and dies, the non-fluorinated photosensitizer shot only once and, along with the target, was almost immediately consumed by the activated or "singlet" oxygen it produced. In short, each use of the non-fluorinated photosensitizers was "a suicide mission." Because of that, in any potential use, new photosensitizers would have to be continually introduced in order to provide continued effect - a costly, impractical and potentially harmful (in the case of medical use) condition.

By fluorinating the photosensitizers, however, Professor Gorun was able to create photosensitizers immune to the ravages of the activated or "singlet" oxygen. Professor Gorun's fluorinated photosensitizers shoot and shoot again and again. In fact, thus far the fluorinated photosensitizers Professor Gorun and his students have created have shown themselves to be "virtually immortal" in the lab.

Because there is no longer a need to continuously replenish the photosensitizers, the research now avails itself to application in numerous commercial, industrial, environmental and medical applications.

Paint
The fluorinated photosensitizers are mixed with a "breathable" polymer matrix paint or coating. The paint itself is silicon-based and has an extremely low carbon content, thus making it not susceptible to the ravages of the activated or "singlet" oxygen produced by the fluorinated photosensitizers. And although the silicon-based matrix paint repels water, it allows oxygen to enter, which, along with light, is necessary for the fluorinated photosensitizers to work. And work they do.

When exposed to light the fluorinated photosensitizers produce these activated or "singlet" oxygen molecules that essentially "patrol" the painted surface, attacking and repelling contaminants and, in some instances, actually changing the molecular structure of the attacking substance to render it inert and incapable of chemically bonding with the paint. In this way, the surface of the painted structure is "cleaned" and the integrity of the underlying material maintained.

Cancer
Less invasive than surgery, the fluorinated photosensitizers are introduced into the body and distribute themselves in tissues they are directed at- including cancerous tissue. In Professor Gorun's more recent work in collaboration with Professor David Sabatino, however, they've studied what may well be the "second generation" in this promising technology in the fight against cancer: coupling the fluorinated photosensitizers with "vectors" or "finder molecules," that may actually seek out and deliver the photosensitizers to the cancer itself.

With either delivery method, when the fluorinated photosensitizers are in place and light is then specifically directed at them, they are expected to work with the naturally occurring oxygen within the body to transform into the "tiny rayguns" that then destroy the cancer cells before them. Afterward, the fluorinated photosensitizers are naturally excreted from the body.

Environmental Cleanup
The same process has shown promise in remediating polluted water, with the fluorinated photosensitizers using the oxygen at large to "deactivate" pollutants within. In addition to the LaGrosa Award bestowed to Karpagavalli Ramji, the research has been lauded by the United States Army as the "discovery of a water purifier," with "potential dual use civilian application in many parts of the world where contaminants - organic and inorganic - impact the potability of water or the availability of water."

Professor Gorun explained, "In all these applications of our research, what we are doing, simply, is taking the power of light and combining it with oxygen and the brilliance of our students to do something useful. As the director of Seton Hall's Center for Functional Materials, it is the essence of what we strive for: the practical application of research and researchers to solve real problems. This is bio-inspired catalysis, and at Seton Hall we have a long and storied history in industry and the scientific community as a focal point in the study of catalysts through our Center for Applied Catalysis. Our work is just one more important step in that journey."