(WHS-P21) USING A SKIN MIMIC SUBSTRATE MODEL FOR MEDICAL ADHESIVE EVALUATIONS
Friday, May 17, 2024
7:30 AM – 5:00 PM East Coast USA Time
Introduction: Current substrates used to evaluate adhesive performance of medical products, such as stainless steel, show minimal correlation with human skin, as their surface energies and moduli are vastly different from the human skin they are trying to emulate. As such, there is an industry need for a substrate that would more accurately represent how adhesives perform on human skin.
Objective: The purpose of this study is to evaluate a new substrate for its ability to produce peel force results similar to that of peel force results gathered from human skin. Using the layers of human skin as a basis for its construction, a prototype skin mimic was created as a multi-layered assembly: the top film layer (representing epidermis), the middle silicone layer (representing dermis), and the bottom anchoring layer (representing subcutaneous tissue/muscle/bone). The mimic was subsequently used to generate peel force data with nine medical tapes, which were then compared to internal clinical peel force data (t=0) of the same tapes for a performance evaluation. Materials/
Methods: Four skin mimics of varying thickness (1.000”, 0.500”, 0.250”, 0.125”) were created. A tensile tester was used to conduct 180-degree peel tests, based off of ASTM D3330/D3330M-04(2018), in order to gather average peel force data for nine distinct medical tapes. Each tape was cut into 1”x5” strips, adhered with a standardized roller onto the skin mimic substrate, allowed to dwell for 1 minute, and peeled off the substrate with the tensile tester. The average peel force for each sample (N/in.) was calculated through the average value of a function (integral method) across a 3” peel interval. Resulting peel force averages for each tape, generated with the skin mimic, were then compared with a previously completed clinical study utilizing the same nine medical tapes. Results/
Discussion: Four out of nine tapes (n=10) showed a statistically significant similarity between mean peel forces on the skin mimic vs human skin. The remaining did not exhibit similarity, primarily due to the large variability of the clinical data vs the high repeatability of the skin mimic data.
Conclusion: The skin mimic showed a correlation with the data from the clinical study on human skin, but with a higher level of repeatability as indicated by the low standard deviation of skin mimic data. A high level of repeatability will be critical when evaluating adhesives for changes in performance, as it becomes increasingly more difficult to attribute differences in results to variations in the adhesive when variability is high due to the method and/or study participants.