Interviewer: Do we also test the safety and efficacy of wound dressings in these tests?
Frederike: No, because these are purely technical measurements using lab samples of wound dressing adhesives. But we have other study designs that can be used in clinical trials for medical devices, but those are far more complex.
Interviewer: Besides adhesive strength, are there other technical test designs?
Frederike: Yes, for instance, there's a wear test. It evaluates the overall adhesive properties of a adhesive dressing—how long it sticks and its comfort level. The standard test lasts 8 days. Adhesive dressings are applied at customer-specified spots, like near joints where there's frequent movement. The volunteers then return typically on Day 3, 5, and 8 for assessments on how much of the adhesive dressing remains intact. At the end, adhesive dressings are removed, and volunteers rate the pain upon removal and overall comfort during wear. Sometimes, we introduce a challenge to see how the plaster deals with real world situations, for example taking a shower. Although adhesive areas shouldn't typically get wet, we've even had protocols where volunteers were instructed to take full baths.
Interviewer: Sounds practical!
Frederike: Exactly. We also have a test where we dye the skin blue. This checks if the top layer of skin, the stratum corneum, comes off with the adhesive dressing. After dyeing the skin blue, the adhesive dressing is then applied over the dyed spot. After 24 hours, the adhesive dressing is peeled off, and the color intensity is measured. There's a control patch without the adhesive dressing to compare. This test allows us to see how much, if any, skin cells came off with the adhesive dressing. We've had instances where there was barely any color left after removal, and this dye is deep ink-blue.
Interviewer: What was the most interesting study on this topic recently?
Frederike: We had one where we wanted to see how many times you could reapply and remove the same exact adhesive dressing.
Interviewer: Thank you for the interesting interview!