Tensile Testing of Two Amniotic Membrane Products: Artacent Wound® and Artacent AC®

Amniotic membrane is a promising biomaterial for regenerative medicine and a plethora of placental membrane products products exist in the market today and are used for varying applications. When assessing and characterizing the multitude of amniotic products on the market, it is important to ensure that each product meets user need for handling capabilities so that the membrane can be properly applied to the wound. One way this characterization can be achieved is via tensile testing using an Instron 5544. The process of tensile testing amniotic products with the Instron 5544 has not previously been well-standardized or optimized for this material. With this study, a standardized test method for tensile testing of dehydrated amniotic membrane has been established. In this study, the established tensile testing procedure is used to distinguish differences in the handling capabilities of Artacent Wound, a dual layer amniotic scaffold, and Artacent AC, a tri-layer amniotic scaffold composed of a layer of chorion between two layers of amnion. In addition, this repeatable test method is also used to assess a modified version of Artacent AC where one of the tissue processing steps has been altered.<br/><br/>Methods:<br/><br/>Tensile Testing<br/>1. Nonslip material is cut to size and applied to Instron Jaw Faces.<br/>2. ASTM D1708 dog bone die cutter is used to cut samples to the proper size and shape.<br/>3. Width and thickness measurements of the sample are taken in triplicate and averaged.<br/>3.The force sensor is calibrated.<br/>4.Tare load of 0.5N is applied to the sample prior to test start.<br/>5. Length measurements of the product are taken.<br/>6. Length, width, and thickness measurements are entered into Bluehill Software.<br/>7. Strain Rate of 0.40mm/min. is entered into software.<br/>8. "Zero displacement" is selected.<br/>8. Test is started until full sample break is achieved.<br/>9. Test is stopped and data is collected.<br/><br/>Data Analysis:<br/>One – Way ANOVA Multicomparison Tukey Tests were used to compare each test group.<br/><br/>Results:<br/>Comparative graphs summarize the failure stress (MPa), failure strain (%) and Young's Modulus (Mpa) of the following test groups:<br/>- Artacent Wound<br/>- Artacent AC<br/>- Modified Artacent AC<br/><br/>Discussion:<br/>There are no significant differences between the measured biomechanical properties of Artacent Wound and Artacent AC, although Artacent Wound has slightly increased strength when compared to Artacent AC.<br/>The modified version of Artacent AC did not show any significant difference when compared to original Artacent AC. However, the modified Artacent AC is shown to have higher Young’s Modulus and failure stress when compared to original Artacent AC. This demonstrates that modifying certain tissue processing steps could be advantageous for improving material handling properties.<br/><br/>Conclusion:<br/>Artacent Wound has increased failure stress and Young’s Modulus when compared to Artacent AC.<br/>Modifying certain steps of the Artacent AC tissue processing procedure is shown to be beneficial for improving handling properties of the scaffold, as it demonstrates increased Young’s Modulus and failure stress when compared to that of original Artacent AC.