Hydrogels are increasingly popular materials used in the medical field, most commonly as delivery vehicles for drugs or as environments for cell culture. As drug delivery vehicles, hydrogels can effectively transport medications within the body to the target location without inducing an immune response. The design of their internal structure typically allows the drug to be released at the correct prescribed rate, ensuring proper absorption and efficacy. 

Though there are a few standards that provide extremely basic guidelines for evaluating the physical properties of hydrogels and other biomaterials, no specific test procedures exist for this material. ASTM F2150 evaluates the properties for biomaterial scaffolds, the under-arching structure for engineered tissues. This standard simply references the more common tensile standards like ASTM D412 and ASTM D882 to serve as starting points for evaluating the tensile properties of these materials.

For the most accurate results it is imperative that these materials be tested in-vitro, surrounded by a saline solution at body temperature. Most tensile testing of hydrogels aims to identify the strength and modulus of the material in a comparative study of hydrogel compositions. To read the full standard, purchase ASTM F2150.

Materials Testing System

Hydrogels are extremely fragile and sometimes cannot withstand side action style grips. In this case, custom shoulder end grips are ideal and can be designed specifically for the customer’s sample. They should be tested as a dog bone shape to improve the chances of failure within the gauge length.

For testing hydrogels we recommend a 6800 Series single column testing system with low-capacity grips and 100 N load cell. If highly accurate strain measurement is needed, Instron's AVE2 is ideal for this application. In order to create a suitable in-vitro environment, Instron's BioBath is required.