Bacterial Biofilm Imaging and Treatment of Chronic Wounds Using Cold Atmospheric Pressure Plasma

Wound healing is often delayed by bacterial biofilm; in fact, it has a 78.2% prevalence in chronic wounds. The bacteria is often resistant to antibiotics and antiseptics. The purpose of this research was to evaluate how effectively bacterial biofilms can be removed from chronic wounds with the use of Cold Atmospheric Pressure Plasma (CAP). CAP is a partially ionized gas operable at room temperature. The general procedure for the experiments was to inoculate chicken samples with a bacterium (Pseudomonas Aeruginosa) and then wait for biofilm growth. Then a Trypan blue (0.04%) staining was performed to turn only the biofilm blue; an image was captured, and finally selective CAP treatment via motorized X-Y stage was performed by using the image to differentiate between the stained bacteria and the tissue. The CAP used Argon gas for the source at 1.37 LPM. As a control, other samples were treated with gas flow only. The resulting treatment images were captured with a monochrome camera, and the biofilm was segmented using MATLAB. Finally, this image was compared to fluorescence imaging of the bacteria which fluoresces green under UV illumination. The results are encouraging. The biofilm was cleared after treatment and no growth was shown after 48 hours. After gas treatment the control experiments showed no reduction in bacteria.