Publication Date

Fall 2010

Document Type

Project Summary

Degree Name

Master of Science


Analytical Chemistry

First Advisor

Patty Fu-Giles, Ph.D.

Second Advisor

Timothy Gsell, Ph.D.

Third Advisor

Karen D'Arcy, Ph.D.


The objective of the proposed study is to develop new materials and methods to manage microbial growth in chronic wounds using phototherapy. Chronic wounds are considered as a worldwide health problem. The most common chronic wounds can be classified into three categories: venous ulcers, diabetic ulcers, and pressure ulcers. Venous ulcers, which usually occur in the legs, account for about 70% to 90% of chronic wounds and can become infected easily. Venous ulcers are sores that develop after veins in the legs have been damaged. These ulcers can penetrate deeply into the skin. Occasionally, if a venous ulcer persists for a long time, skin cancer might develop at the edge. It has been shown that several bacteria species can colonize chronic wounds as highly persistent biofilm communities. Chronic wound pathogenic biofilms are host-pathogen environments that colonize and exist as a cohabitation of many bacterial species that cooperate to promote their own survival and the chronic nature of the infection. Bacterial biofilms are highly organised microbial communities living within a protective extracellular matrix. They are difficult to detect and highly resistant to immune or antibiotic elimination. There are specific major populations of bacteria that are evident in the biofilms of all chronic wound types. Species including Staphylococcus, Pseudomonas, Peptoniphilus, Enterobacter, Stenotrophomonas, Finegoldia, and Serratia spp are found to be common chronic wound pathogens.

Our preliminary studies have shown that non-toxic vitamins such as riboflavin (vitamin B2) and cobalamin (vitamin B12) can produce singlet oxygen and free radicals upon irradiation. Furthermore, our data has shown, upon irradiation with low energy visible light, riboflavin and cobalamin both can cleave and damage native double-stranded DNA. It is very important to use low energy visible light in the process owing to it penetrates human tissue much deeper then the high energy UV light. Also, visible light will not damage normal human cells like UV light. The delivery of visible light is a localized process normally using laser light transported by optical fibers. We have the knowledge and technology to discover and develop the drugs as well as design a portable laser system for PACT that can be patented and eventually commercialized.