## Honors Theses

Symes, Steven J.

#### Department Examiner

Mebane, Robert; Rybolt, Tom; Thomas, Tricia

#### Department

Dept. of Chemistry

#### Publisher

University of Tennessee at Chattanooga

#### Place of Publication

Chattanooga (Tenn.)

#### Abstract

Decreasing the risk of infection following surgery for traumatic bone breaks is a major focus of the medical and scientific community. Drug delivery devices are emerging as powerful solutions for combating infection following these procedures. Current devices, however, suffer several drawbacks including poor antibiotic release rate and control the devices themselves not being biodegradable. This thesis studies the \textit{in vitro} release rate for antibiotics tobramycin and vancomycin from a biodegradable medical implant. Antibiotics, collagen, and bone growth factors are incorporated into Poly(lactide-co-glycolide)-based electrospun nanofibers by local company eSpin for development. The drug-loaded nanofibers are immersed in phosphate buffered saline (PBS) at 37$^{\circ}$ C and assayed at specific time intervals to monitor antibiotic elution rate. The high concentration of phosphate and inorganic salts in PBS require a clean up step before quantification using ultra performance liquid chromatography tandem mass spectrometry. Several methods for clean-up are examined, including: dialysis, liquid-liquid extraction, and three solid phase extractions. While no single method successfully extracted both antibiotics from the PBS matrix, this survey of methods provides direction for future work in developing this novel drug delivery device.

#### Acknowledgments

First and foremost, I need to acknowledge Dr. Steven Symes for supporting me during this work and for his mentorship during my tenure at UTC. Caitlin Quinn has provided a significant amount of help with lab work, presentation preparations, and in providing motivation to finish this thesis. I would also like to acknowledge the efforts of Marcus Morgan, Karl Green, and Daniel Shults for assisting in lab work for this project. A large thank you is due to the Grote Chemistry fund, the US Army, the UT College of Medicine and the Provost Student Research Awards for supporting myself and this project over the last two years.

#### Degree

B. S.; An honors thesis submitted to the faculty of the University of Tennessee at Chattanooga in partial fulfillment of the requirements of the degree of Bachelor of Science.

5-2015

#### Subject

Biomedical engineering; Drug delivery devices; Medical instruments and apparatus -- Design and construction

#### Keyword

Solid Phase Extraction; HPLC-MS/MS ; Nanofibers; Dialysis; Tobramycin; Vancomycin

Chemistry

Theses

ix, 81 leaves

English