cytotoxicity testing

New Approaches to Assessing Biocompatibility for Medical Devices

Audrey Turley

The regulatory environment for biological safety evaluation of medical devices is changing rapidly. Biological safety evaluations following ISO 10993 have typically been addressed with biocompatibility  testing on animals; however, alternate options are now available using literature research and chemical characterization tests when appropriate to reduce animal testing. Considerable progress is being made in the development and standardization of new in vitro test methods; particularly for cytotoxicity, sensitization and irritation, the basic tests performed for any medical device regardless of the device’s application. These alternative in vitro methods provide multiple benefits, including: less sample amount, less time required to perform the test, and reduced animal use.

Click here to view Research Scientist Audrey Turley’s presentation from MD&M West 2016.

What will be learned:
• Learn how to use a risk assessment approach for process and material changes
• Understand how to use material and chemical characterization to reduce animal testing
• Update on development of alternative in vitro testing methods for irritation and sensitization


Nelson Laboratories On Demand Webinar: The Power of Chemical Characterization to Assess Changes in Your Medical Device

Nelson Laboratories Cytotoxicity Testing, Biocompatibility Testing

Click Here To Watch Nelson Laboratories’ On Demand Webinar

“Every change will have a different biocompatibility impact depending on the type of variable being introduced or taken away from the medical device.”
– Alexa Tatarian, Nelson Laboratories, Inc. Study Director

Join Nelson Laboratories’ biocompatibility expert Thor Rollins and Study Director Alexa Tatarian for on demand webinar The Power of Chemical Characterization to Assess Changes in Your Medical Device. While initial instinct may compel device manufactures to perform a costly re-test when alterations are made, this webinar highlights chemical characterization, a cost effective limited scope alternative for evaluating the impact of change on the overall biocompatibility of a medical device.  If you are a medical device manufacturer, don’t miss the opportunity to learn more about chemical characterization.

Webinar highlights:

  • Typical changes manufacturers encounter
  • Evaluating the impact of the change in relation to patient safety
  • Testing options available to evaluate changes
  • Case studies

Medical device manufacturers will walk away from this webinar with a better understanding of the opportunity to use chemical characterization to evaluate changes that may occur in their medical device from time to time. Attendees will also be reminded that any change no matter how major or minor requires testing, but that testing can be customized to account for the type of change because not all changes require the same level of testing. WATCH NOW!

ISO Meeting and Biocompatibility Standards Update, Mishima, Japan

by Thor Rollins, Biocompatibility Expert, Nelson LaboratoriesGC

I recently attended ISO (International Organization of Standardization) meetings in Mishima, Japan to participate in updating various biocompatibility testing standards. These updates are intended to reflect the best care and safety possible, regarding biocompatibility, for any given device. The updates discussed at this series of ISO meetings included the following:

  • Compound Limits: Safety limits need to be determined for each compound that can come off of a medical device during use. Currently, Ethylene Oxide (EO) gas is the only compound listed in an ISO standard that has a residual limit. However, the plasticizer diethylhexyl phthalate (DEHP), a plastic compound used in medical devices such as tubing, will likely have a limit set in the future.
  • Cytotoxicity Test: A test wherein a device, or portion of a device, is applied to living cells to see how the cells react to the materials used in the manufacture of the device. This is considered the most sensitive biocompatibility test and is a great screening tool for medical devices. The current cytotoxicity tests are qualitative; however the standard is now emphasizing the use of a quantitative version of the cytotoxicity test.   The early results from these quantitative methods have shown an increased sensitivity over the qualitative methods. A series of round robin tests are being planned to verify that the quantitative test method is consistently more sensitive.  These tests will then be followed by a discussion of clinical relevance of making the test more sensitive.
  • Different Population Limits of Chemicals: A person’s healthy limits for chemical exposure from using a medical device can vary depending on body size. For this reason, new standards for these limits are being discussed to introduce new limits according to the physical characteristics of the target population of the intended recipient. Currently, the industry standard is set for an average person weighing 70 kilograms (154 pounds), much higher than the weight of a child or infant. The new standard will consider the weights of intended populations, such as small children and infants.
  • Gas Path Devices: When using delivery systems that are intended to supply gases needed for medical purposes, compounds from those devices can come off and enter the human body. For this reason, it is necessary to standardize the effects of these compounds, in addition to the amount of compounds that will be allowed to be released during use.

Standards are reached through global consensus and serve to make the industry more efficient and effective, in addition to providing additional safety. As these standards are implemented, Nelson Laboratories will ensure the standards are met with the same quality as before.