|Lay, Jr, Donald - Don|
Submitted to: American Society of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/2005
Publication Date: 7/24/2005
Citation: Moulton, K., Lovell, F., Williams, E., Ryan, P., Lawrence, M., Karsi, A., Lay Jr, D.C. 2005. Application of glycerol as an optical clearing agent to enhance photonic transference and detection of salmonella typhimurium through pig skin. American Society of Animal Science. 83(1)246.
Technical Abstract: The objective of this investigation was to evaluate glycerol (GLY) and GLY+DMSO as an agent to optically clear pig skin and increase photonic transference and detection of photon emitting Salmonella typhimurium (S. typh.-lux; transformed with plasmid lux CDABE), in a laboratory model for Salmonella detection in swine. Pig skin obtained from a slaughter facility after hair removal was processed in the lab to remove the subcutaneous fat and measured for thickness. A 96-well plate containing S. typh.-lux was imaged for 5 min using a photon counting camera. Skin (3 mm thick) was then placed over the plate containing S. typh.-lux and imaged for 5 min. The skin was then treated with varying ratios of GLY, DMSO and saline (PBS) in a dose- and time-dependent manner and the plate imaged again for 5 min. The ratio of photonic emissions comparing treated vs untreated skin and no skin (control plates) were used for analysis (n=8 experimental replicates). Treatment for 4 h with 50% GLY-PBS and 50:30:20% GLY:DMSO:PBS increased (P<0.05) photonic emissions (4.9 +/- 0.8 and 6.5 +/- 0.9%, respectively) compared to skin not treated (0.24 +/- 0.05%), 100% PBS (0.20 +/- 0.03) or 30:70% DMSO:PBS (0.50 +/- 0.08). Altering the ratios of DMSO (10, 20, 30, 40, and 50%) in the presence of 50% GLY(and PBS to volume) demonstrated that DMSO at 20 and 40% (13.8 +/- 1.2 and 14.4 +/- 1.1%, respectively) increased (P<0.05) photonic emissions compared to 10% DMSO (10.8 +/- 1.3%) and 50% GLY:PBS alone (10.4 +/- 1.0), but was not increased (P>0.05) from DMSO at 30% and 50% (12.8 +/- 1.0 and 12.3 +/- 1.1%, respectively). Treatment of skin with 50% GLY and 50:30% GLY:DMSO did not differ (P>0.10) in photonic emissions at 30 min, 1, 2, 4, or 8 h post-treatment; and both treatment groups exhibited greater (P<0.05) photonic emissions than no treatment, DMSO alone, or PBS at 2, 4, and 8 h. These data indicate that GLY and GLY+DMSO may be used as effective optical clearing agents on pig skin when treated for 4 or 8 h to allow for an increased detection of emitted photons from S. typh.-lux through the skin.