Analytical Medical Device Development and Failure Testing Strategies
Deena Conrad-Vlasak, Business Development
Many of today’s medical devices use polymeric material to take advantage of the light weight, durability, and tunable flexibility. However, influences such as light, heat, oxygen, corrosive materials, and sterilization processes can lead to degradation of these materials and possible device failure. Additives can be incorporated to add clarity, color, mechanical properties, and inhibit degradation, but these additives can increase the complexity of the formulations and introduce the risk of unwanted leaching. It is well documented that leaching may pose a safety risk to the patient and has the potential to interfere with the efficacy of active ingredients. (1-3)
Medical Device Development Testing
Each medical device has a unique and specific set of test requirements that must be reported for approval by various regulatory bodies. This biocompatibility testing is detailed in the ISO 10993 standards. It is important to understand the testing requirement variations for each targeted regulatory body and each phase in the development process. Developing a test plan may reduce the cost of unnecessary or missed tests which can significantly delay marketing the device. Early design evaluation may not require testing under GLP or cGMP that is usually necessary for regulatory submissions. So, finding a laboratory that has ISO certification and is registered with the FDA is an important step. These labs may follow established guidelines and methods that are well recognized by regulatory agencies. However, for new, cutting edge devices, finding a laboratory that has the capability of providing custom methods for material and product specific testing is important. Analytical testing requirements such as material characterization, impurity profiling, leachables and extractables, packaging, and ethylene oxide sterilization residuals are important, as the information obtained is directly relevant to a patient. This type of testing specifies the components in a medical device, and promotes consistent manufacturing standards, helping to mitigate product safety risks, and improved quality at all stages of development. In cases where material or vendor change is needed, it may be necessary to evaluate and compare the safety profile of the old material or process with the new.
Device Failure Testing
A device failure can be devastating both to the patient and the manufacturer. The urgent resolution of the failure is critical. Expert analysis can often help determine the cause of the failure allowing the manufacture to make corrections to prevent re-occurrence. The main types of failures are contamination, physical failure, manufacturing defects and improper material selections (4).There are various analytical techniques such as Fourier transformed infrared spectroscopy (FT-IR), microscopy, and thermal and mechanical testing which are used to determine the failure mode. If contamination or material issues are believed to be the cause of failure, testing such as liquid and gas chromatography, mass spectrometry, and size exclusion chromatography may be used.
To mitigate risk and ensure quality of a medical device it is important to understand the testing requirement of each regulatory body for which the device will be marketed. It is also important to choose a laboratory that has the relevant testing capabilities, and knowledge of the correct and accepted standards. Partnering with a laboratory to create a testing plan may decrease the time to market by avoiding incomplete or unnecessary testing.
3)Extractable and Leachables Testing for Medical Applications, Michael Ruberto, Ph.D Material Needs Consulting, LLC
4)Five Common Causes of Medical Device Failure, Lisa Grasel, Impact Analytical (Midland, MI)