Thor Rollins

Considerations for Sterilization and Biocompatibility of 3D-Printed Orthopedic Devices

Thor Rollins, Martell Winters, and Matthew Jorgensen, PhD collaborated on a whitepaper that is available for download: Considerations for Sterilization and Biocompatibility of 3D-Printed Orthopedic Devices

This whitepaper is an in-depth look at the various biocompatibility and sterilization considerations surrounding 3D-printed orthopedic devices. 3D-printed orthopedic medical devices are gaining attention and popularity due to their potential for enhanced biocompatibility, customizability, and cost-effectiveness. As of late 2015, FDA had cleared more than 85 total 3D-printed medical devices, with more regulatory clearances on the horizon.

The whitepaper is available for download on the Qmed website or click HERE.

LIVE Webinar: How to Develop a Risk-Based Safety Evaluation per New US FDA Guidance

Register HERE for the three-day live webinar series “How to Develop a Risk-Based Safety Evaluation per New US FDA Guidance” presented by Nelson Laboratories’ experts: Thor Rollins, Sarah Campbell, and Audrey Turley.

This three-day webinar will incorporate the new US FDA guidance on biocompatibility into the three main steps in developing a Biological Safety Evaluation (BSE): Biological Evaluation Plan (BEP), Testing Options, and Biological Evaluation Report (BER). Composed of three one-hour presentations followed by Q&A sessions, the webinar will cover each step in developing a BSE in detail. This webinar will provide insight into regulatory expectations when it comes to evaluating device safety.

The presenters for this three day webinar provide a combined 50 years of experience in their field of expertise. Thor Rollins is a leading biocompatibility expert and has worked closely with medical device companies and the FDA for over 15 years. Dr. Sarah Campbell is a board certified Toxicologist with an extensive 17 year background in practicing and using analytical chemistry for toxicological evaluation. This combination of expertise is important to in order to handle the important aspects of material/chemical characterization and toxicological risk assessment. Audrey Turley has 20 years of experience working in research, laboratory, and test design functions in the medical device industry.


The new FDA guidance document for ISO 10993-1 focuses on a risk based approach to biocompatibility. The first step is to develop a BEP. This webinar will go over the thought process and information needed to develop a useful testing plan.

Date: August 30, 2016
Time: 11:00 AM PDT | 2:00 PM EDT
Duration: 60-minutes


Thor S. Rollins, B.S., RM (NRCM)
Senior Scientist


Justifying out of testing using chemical characterization vs performing full biocompatibility testing. The first important step in determining the risk of a medical device to a patient is to know and understand your materials and processes. This webinar will go over the steps in evaluating device materials and an extractable/leachable chemical testing needed to demonstrate biocompatibility.

Date: August 31, 2016
Time: 11:00 AM PDT | 2:00 PM EDT
Duration: 60-minutes


Sarah Campbell, PhD, DABT


The ISO 10993-1 and new FDA guidance document asks you to write a BER to demonstrate that the identified risks have been mitigated. We will go over the information needed and the important points that should be included in the report.

Date: September 1, 2016
Time: 11:00 AM PDT | 2:00 PM EDT
Duration: 60-minutes


Audrey Turley, B.S., RM (NRCM), CBA (ASQ)
Research Scientist

U.S. ISO Certified Experts Announced


Thor Rollins, Michelle Lee, and Audrey Turley have been accepted as U.S. experts to four working groups in the Biological Evaluation ISO Technical Committee 194: WG5 (Cytotoxicity – Thor), WG8 (Sensitization and Irritation – Michelle), WG9 (Effects on blood – Michelle), and WG6 (Genotoxicity, Carcinogenicity, and Reproductive Toxicity – Audrey). This placement allows participation in the annual ISO meetings to discuss changes to the ISO 10993 and movements surrounding the approach to biocompatibility of medical devices. These meetings have recently been closed, and only those that are nominated and accepted by the co-chair of the respective working groups are allowed to attend and participate in the international annual meeting. Meet the experts:

Thor Rollins started his career at Nelson Laboratories as the study director over cytotoxicity testing. He is familiar with the test procedure and can speak to its application to medical devices providing a deep knowledge of all the complexities that can occur in cytotoxicity testing. Thor frequently works with clients who run into issues with cytotoxicity and need help mitigating patient risk.

Michelle Lee has been highly involved in several ISO round robins over the last few years including a Hemolysis, Complement, and currently an in vitro irritation round robin. Nelson Laboratories have been the top testing laboratory involved providing input on sample type, sample preparation, and protocol development for these projects. Michelle is also working to develop an in vitro sensitization assay using 3D human tissues.

Audrey Turley was one of the key personnel in bringing the in vitro chromosomal aberration assay in-house at Nelson Laboratories. Once the test was validated, she stepped in as the study director for the next six years. Currently, Audrey is working as a technical consultant to help clients perform risk assessments to address carcinogenicity risks.

Nelson Labs Experts Invited to Present at Joint Conference

Thor Rollins, consulting manager, and Audrey Turley, research scientist, have been invited to speak at the joint conference of the Association of Analytical Communities Southern California Section (AOAC SCS) and Food and Drug Agency (FDA) 2016 Spring Conference. Rollins and Turley will be presenting the morning of Wednesday, April 27 at Chapman University, School of Pharmacy, Irvine. Click here for the full agenda.

DSC01871Rollins will be presenting on the application of chemical characteristics to medical devices. His presentation will cover how the industry is taking extractible and leachable applications and applying them to medical devices. The discussion will focus on what the challenges are, what benefits they have, where we are right now with the program and speculate about what these applications mean to the future of medical devices.

“I am excited for the opportunity to contribute to the discussion with colleagues and FDA experts about the future of the science behind biocompatibility and medical devices,” said Thor Rollins.

Turley will be presenting on in vitro alternatives to traditional animal testing. Specifically, she will be talking about in vitro irritation, sensitization and thrombogencity.

Visit the Nelson Labs website to view recent presentations by Rollins, How to Use Biocompatibility to Evaluate Changes in Medical Devices, and Turley, New Approaches to Assessing Biocompatibility for Medical Devices.

How to Use Biocompatibility to Evaluate Changes in a Medical Device

Thor Rollins is a Biocompatibility Specialist and Vivo Section Leader at Nelson Laboratories, Inc.Medical devices often go through many changes throughout their normal product lifecycles. Whenever a device goes through one of these changes, it should also undergo a review to determine the impact the change had on the biological safety of the device.  While many changes have little impact and can be justified based on the minimal risk, other changes (or a compilation of changes) could pose a serious biological safety impact and require a revalidation.  This presentation will cover the questions manufacturers need to ask to determine what impact changes may bring to their devices and the testing that should be performed to measure the impact of these changes.

Click here to view a thorough, yet dynamic, presentation by Thor Rollins, Senior Scientist at Nelson Laboratories, Inc.

Evaluating The Impact of Change with Chemical Characterization

Analyst performing FTIR Test to identify residuals

Analyst performing FTIR Test to identify residuals.

When dealing with orthopedic medical devices, even small changes in the manufacturing process or device materials can impact patient safety. With these changes comes the risk of introducing new compounds that may leave residue on the device or leach harmful compounds that put the patient at risk. Because of the high patient risk, the biocompatibility of the device must be re-evaluated after any change.

The most thorough method to determine the effect of a change is to repeat the biocompatibility tests that were performed in the original submission to bring the device to market. However, this can be costly and time-intensive. One alternative is chemical characterization testing. Chemical characterization test methods characterize the device materials and determine the compounds that may leach or extract from the device. Chemical characterization, combined with specific biocompatibility tests, is a more cost effective and efficient way to evaluate the impact of a change in the manufacture of a device.

Common changes orthopedic device manufacturers encounter are generally outside of their control. These changes include alterations to the device material or vendor supply. Internal changes are also implemented to improve the device or the manufacturing process which can impact the biocompatibility of the device.

When a change occurs, the manufacturer must evaluate the impact of the change on the device as a whole. A few key characteristics of evaluating change include:

  • Evaluate any new material or compounds that could be introduced to the patient as a result of that change.
  • Evaluate how much the change affects the patient contacting portion of the device.
  • If the affected portion of the device does not have direct patient contact there may be less testing required than a change that would affect the direct patient contacting surface areas of the device.
  • If a processing change has occurred, evaluate whether or not the new process removes residuals as effectively as the original process.

Because every orthopedic device is unique, there are many ways to assess the impact of a change. The potential impact to the patient must be evaluated with any change and chemical characterization is one way manufactures can evaluate that change.

Chemical characterization testing is most effective when the original device configuration is compared to the device after a change has occurred. If the characterization of the two devices is shown to be similar, fewer biocompatibility tests may need to be repeated. A test plan, along with a risk assessment, is the most successful approach to take when evaluating the impact of a change to the overall biocompatibility and patient safety of a device.

For more information on using chemical characterization to evaluate changes in medical device manufacturing we recommend Thor Rollins’ and Alexa Tatarian’s ODT Magazine article, “How to Approach Change in Orthopedic Device Manufacturing,” as well as their complimentary on-demand webinar, “The Power of Chemical Characterization to Assess Changes.” You may also visit Nelson Labs online at for more information about our biocompatibility testing laboratory services.