Predicting the Future Using Accelerated Aging: Start Early in the R&D Process
Karl Hemmerich, president of Ageless Processing Technologies, previews some advice he’ll be sharing in depth at his MD&M West conference session on Thursday, February 13.
For predicting how medical-device and pharmaceutical packaging and materials will age and degrade over time, “crystal balls work best, but they’re hard to come by,” jokes Karl Hemmerich, president of Utah-based Ageless Processing Technologies and a conference speaker at MD&M West. Hemmerich’s talk, titled “The Current Art of Accelerated Aging: Conducting Accelerated-Aging Tests To Provide Experimental Data in Support of Performance and Shelf-Life Claims,” will forego discussion of crystal balls in favor of the history, theory, and mechanisms behind accelerated aging and how it can accurately predict changes in product properties over time.
While the science and much of the methodology are not new, Hemmerich says, gaining a solid understanding of accelerated-aging techniques and when and how to employ them is well worth medical- and pharmaceutical-packagers’ time and attention.
When a company is “in R&D mode, especially,” Hemmerich says, “it needs to knock off designs that aren’t going to work. So you use accelerated-aging techniques to get a look forward and cross off some of your options. If you have five potential materials you can use, do accelerated aging to eliminate two, three, or four of them. Go with your optimum choice instead of simply settling for the one you used last time.”
After all, to effectively develop a product, “you have to understand what that product is, how it functions, how it’s stressed, what the materials are, and what causes those materials to fail,” Hemmerich states. “What are your failure points? And what will cause failure?” If you can’t find that crystal ball, “put some science” to these questions, Hemmerich will tell attendees of his talk, by using collision theory, on which accelerated-aging is based, and applying heat, oxygen, radiation, or your accelerant of choice. Doing so will likely reveal “the Achille’s heel of your product” and a time relationship, Hemmerich shares.
During his many years in product development, Hemmerich has observed a growing understanding by industry and regulatory agencies alike of accelerated aging and its benefits, but “there’s still a lot of mystery” surrounding it, he says, and no definitive regulatory statement on accelerated aging exists. Some ASTM standards address the topic, such as ASTM D3045-92(2010), Standard Practice for Heat Aging of Plastics Without Load, which Hemmerich will address in his MD&M talk, as well as AAMI TIR 17:2008, Compatibility of Materials Subject to Sterilization and relevent ISO standards. “And FDA surely knows about accelerated aging and will comment on 510k submissions or similar documents if it believes testing has been done improperly,” he says. But some inherent mystery remains, because accelerated aging is, of course, modeling. It’s not a precise experiment but rather an estimate.
Maureen Kingsley, Writer, Copyeditor, and Proofreader