Medical Adhesives Mechanical Testing Solutions
Medical adhesives are specialized substances used to bond medical devices, tissues, or other components together. They must comply with strict biocompatibility requirements and are vital in surgeries, wound care, and medical equipment manufacturing. Adhesives used in medical applications require mechanical testing to ensure their strength, durability, and compatibility with various substrates. Sutures are often classified as medical adhesives because they function to mechanically close and secure tissue interfaces, similar to how adhesives bond surfaces together.
ADMET testing systems are trusted by leading medical device manufacturers, universities, and research laboratories to determine the mechanical properties and endurance limits of biomaterials, medical devices and implants. Our systems meet FDA 21 CFR part 11 requirements and are capable of performing tension, compression, flexural, adhesive, torsion, axial-torsion and planar biaxial tests according to ASTM and ISO standards. Our ability to design a system to fit specific needs allows ADMET to provide testing solutions for even the most unique and demanding applications.
Types of Medical Adhesives
Tissue adhesive for the topical approximation of skin
A tissue adhesive for the topical approximation of skin is a device intended for topical closure of surgical incisions, including laparoscopic incisions, and simple traumatic lacerations that have easily approximated skin edges. Tissue adhesives for the topical approximation of skin are Class II medical devices and may be used in conjunction with, but not in place of, deep dermal stitches.
Tissue adhesive for non-topical use
A tissue adhesive for non-topical use is a Class III medical device that is used for adhesion of internal tissues and vessels. Examples of use include the embolization of brain arteriovenous malformation and ophthalmic surgery,
Tissue adhesive with adjunct wound closure device intended for the topical approximation of skin
A tissue adhesive with adjunct wound closure is a Class II medical device intended for topical application only to hold closed easily approximated skin edges of wounds from surgical incisions, including punctures from minimally invasive surgery, and simple, thoroughly cleansed, trauma-induced lacerations.
Types of adhesives include:
- Cyanoacrylate Adhesives: Quick-setting and used for minor wound closures.
- Silicone-Based Adhesives: Known for flexibility and biocompatibility, often used in skin attachments and prosthetics.
- Epoxy Resins: Offer high mechanical and thermal resistance; used in bonding medical devices.
- Acrylic Adhesives: Provide high tensile and shear strength; adhere well to various materials.
- Pressure-Sensitive Adhesives (PSAs): Used in medical tapes and patches; adhere with applied pressure.
- Polyurethane Adhesives: Versatile with excellent wear resistance; often used in flexible medical devices.
- Fibrin Sealants: Derived from blood components and used for hemostasis during surgical procedures.
- Hydrogel Adhesives: Water-based and gentle on the skin; commonly used in wound care and ECG electrodes.
Sutures
Sutures often considered the baseline for wound closure techniques, play a crucial role in the medical field. When it comes to developing new medical adhesives, sutures serve as a comparative standard for evaluating the efficacy and mechanical properties of adhesive products. This assessment includes tensile, shear, and peel tests to ensure that medical adhesives can meet or exceed the performance characteristics of traditional suturing methods. By understanding the mechanical benchmarks set by sutures, developers, and manufacturers can optimize adhesive technologies for various medical applications.
Common Medical Adhesive Test Types & Standards:
Peel Testing is a mechanical testing procedure used to measure the adhesive strength of materials by assessing the force required to separate two bonded surfaces. Some peel testing standards of medical adhesives include:
- ASTM F2256 Strength Properties of Tissue Adhesives in T-Peel by Tension Loading
- Tensile test method to compare and characterize the peel strength of different types of tissue adhesives
- ASTM D3330 Standard Test Method for Peel Adhesion of Pressure-Sensitive Tape
- Six different test methods for testing the peel adhesion strength of pressure sensitive tape
Shear Testing is a mechanical test that evaluates the ability of a material to withstand forces that can cause the internal structure to slide against itself. Some shear testing standards of medical adhesives include:
- ASTM D3654 Standard Test Methods for Shear Adhesion of Pressure-Sensitive Tapes
- Test method to measure the ability of pressure-sensitive tapes and labels to remain adhered under constant load applied parallel to the surface of the tape and substrate
- ASTM F2255 Strength Properties of Tissue Adhesives in Lap-Shear by Tension Loading
- Tensile test method to measure and compare the lap-shear strength of tissue adhesives
Tensile Testing is a mechanical test that involves pulling a material apart and measuring the force and deformation to assess its strength, elasticity, and elongation properties. Some tensile testing standards of medical adhesives include:
- ASTM D882 Standard Test Method for Tensile Properties of Thin Plastic Sheeting
- Test method to determine the tensile properties of plastics in the form of thin sheeting
- ASTM D2256 Thread and Yarn Tensile Testing
- Test method to determine the breaking strength, elongation, and energy of threads, yarns, or other single strand textiles. (Often used for sutures)
- ASTM F2258 Tensile Strength of Tissue Adhesives
- Tensile test to measure and compare the adhesive strengths of tissue adhesives
- ASTM F2458 Wound Closure Strength of Tissue Adhesives
- Tensile test method to measure and compare the wound closure strength of tissue adhesives
Mechanical Properties Measured
Bonding Strength: Mechanical testing assesses the adhesive’s ability to create strong bonds between different materials, tissues, or surfaces. This is crucial for adhesives like wound dressings, where secure adhesion is required for effective wound closure and protection.
Material Compatibility: Medical adhesives must be compatible with a wide range of materials, including skin, tissues, and other medical components. Testing helps identify potential interactions or reactions that could compromise the adhesive’s performance.
Durability: Adhesives used in medical applications must maintain their bond strength over time. Mechanical testing simulates real-world conditions to assess how the adhesive withstands various stressors and maintains its integrity.
Tensile Strength: Medical adhesives must have an appropriate tensile strength for their applications. Tensile strength measures the maximum stress a material can withstand in axial tension before failure. High tensile strength is critical for applications like surgical sutures and other wound closing adhesives, ensuring that the adhesive can withstand the mechanical stresses it will encounter in a physiological environment.
Have any questions on Medical Adhesive test types or standards?
What equipment do I need for medical adhesive testing?
To perform mechanical testing on medical adhesives, you will need a testing frame equipped with the appropriate fixture to clamp the test specimen, a load cell, and a controller. The type of testing system required will be dependent on the adhesive tested, the type of test, and the required calculations.
Testing Frame
eXpert 7600 – Single Column Testing Machine
The eXpert 7600 is a popular medical adhesive testing machine due to its ability to produce accurate results in an affordable and compact package.