Identification of the degradation products of a crosslinked polyester using LC-MS

In the process of developing new biomedical devices, in addition to meeting the required criteria for their intended applications, it is imperative to also identify the degradation products over the lifetime of their intended use. Determining the major degradation products from a device is an important consideration when completing the biological evaluation of medical devices under the ISO 10993 series guidelines. Furthermore, adequate identification of the degradation products may provide preliminary insights into potentially toxic products that may arise as the device degrades. We developed a method that can be used to identify the degradation products of a polyester intended to be used as a medical device. A biodegradable polyester prepared from thiomalic acid, 1,8-octanediol and maleic acid and its nitric oxide (NO)-releasing analogue degraded over a 10-week period was used as a model system. Using a reproducible liquid chromatography-mass spectrometry (LC-MS) method, we resolved and identified major component over the degradation process. Our method highlights the advantages of using LC-MS to accurately identify the components of degradation and provides a framework for future biomedical device studies. (C) 2019 Elsevier Ltd. All rights reserved.