Adhesives are widely used in the medical device industry for dental implants, bone cements, and wound closure products. Wound closure products include tissue adhesives that can be found in bandages, secondary dressings, and a variety of surgical sealants. The adhesive strength of these products must be well defined. An adhesive that isn’t strong enough may result in a wound that heals poorly, or it can lead to an infection. If an adhesive is too strong, it may damage the underlying tissue or cause the patient unnecessary pain when removing. A fundamental challenge with testing bio adhesives is characterizing adhesive strength in physiologically relevant conditions.
Soft tissue substrates should be tested under physiologically relevant conditions, most preferable in a bath or temperature controlled enclosure at 37°C. The BioBath with submersible pneumatic grips is recommended. The grips and pull rod that attach to the force transducer are designed to minimize buoyancy chances during low force testing. We also recommend a low capacity load cell, given that adhesive strength for biological applications is typically under 10-20 N. Bluehill® Universal's Peel, Tear, Friction Module is ideal for this test type in order to measure first peak force, average force over the seal, and average force per width of the specimen.