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Thrombus formation in blood-contacting medical devices is a major concern in the medical device industry, limiting the clinical efficacy of these devices. Further, a locally formed clot within the device has the potential to detach from the surface, posing a risk of embolization. Clot embolization from blood-contacting cardiovascular devices can result in serious complications like acute ischemic stroke and myocardial infarction. Therefore, clot embolization associated with device-induced thrombosis can be life-threatening and requires an enhanced fundamental understanding of embolization characteristics to come up with advanced intervention strategies. Therefore, this work aims to investigate the adhesive characteristics of blood clots on common biocompatible materials used in various cardiovascular devices. This study focuses on characterizing the adhesion strength of blood clots on materials such as polytetrafluoroethylene (PTFE), polyurethane (PU), polyether ether ketone (PEEK), nitinol, and titanium, frequently used in medical devices. In addition, the effect of incubation time on clot adhesion is explored. Results from this work demonstrated strongest clot adhesion to titanium with 3 h of incubation resulting in 1.06 ± 0.20 kPa detachment stresses. The clot adhesion strength on titanium was 51.5% higher than PEEK, 35.9% higher than PTFE, 63.1% higher than PU, and 35.4% higher than nitinol. Further, adhesion strength increases with incubation time for all materials. The percentage increase in detachment stress over incubation time (ranging from 30 min to 3 h) for polymers ranged from at least 108.75% (PEEK), 140.74% (PU), to 151.61% (PTFE). Whereas, for metallic surfaces, the percentage rise ranged from 70.21% (nitinol) to 89.28% (titanium). Confocal fluorescence imaging of clot remnants on the material surfaces revealed a well-bounded platelet-fibrin network at the residual region, representing a comparatively higher adhesive region than the non-residual zone of the surface.
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This content will become publicly available on May 3, 2026
ThermoTape: A Temperature-Responsive Medical Adhesive Minimizing MARSI Risks with Adaptability Across Applications and Wear Durations
Abstract Medical adhesives are vital for securing wearable sensors, wound dressings, and critical medical devices. These adhesives must balance strong adhesion with patient comfort, especially when used over extended periods. Adhesives that maintain their efficacy for more than two weeks are essential for continuous monitoring devices, as they enhance diagnostic accuracy and reduce dressing changes, minimizing patient discomfort and infection risk. However, current long-wear adhesives often use aggressive acrylics that can cause skin injuries. To overcome these limitations, we developed an advanced ThermoTape offering temperature-responsive properties with a polyurethane backing for more than 14 days of wear. A double transfer coating process fabricated PU-ThermoTape, with surface morphology characterized using Atomic Force Microscopy. Differential Scanning Calorimetry and thermography determined the optimal removal window. Peeling strength tests were conducted at room and elevated temperatures to assess performance. In vitro, PU-ThermoTape displayed an average peeling strength of 0.3 N/mm at 25 °C, decreasing by 75% when heated to 45°C, with an optimal removal window of approximately 2.5 minutes. The tape demonstrated excellent skin conformity with its polyurethane backing. In a 14-day wearability study with seven volunteers, PU-ThermoTape outperformed Tegaderm, maintaining temperature-responsiveness and allowing unrestricted daily activities throughout. PU-ThermoTape provides robust adhesion, high skin conformity, and facilitates gentle removal after brief warming, positioning it as a versatile adhesive suitable for various applications with different duration requirements.
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- Award ID(s):
- 2234356
- PAR ID:
- 10588506
- Publisher / Repository:
- ASME - The American Society of Mechanical Engineers
- Date Published:
- Journal Name:
- Journal of Medical Devices
- ISSN:
- 1932-6181
- Page Range / eLocation ID:
- 1 to 13
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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