Stability analysis on class III medical devices

The stability studies of a medical device represent one of the most important analyses within the medical device lifecycle. Their results are unavoidable data that must be included in the technical documentation examined by notified bodies, organs responsible for the conformity assessments to European regulations. Stability is a measure of the device ability to maintain the initial properties and the characteristics owned at the time of manufacture (time 0). Whenever stability is studied on products stored under specified conditions, those studies are termed real-time stability studies. Whereases, if the product is subjected to accelerated aging, achieved through the application of external stresses, they are called accelerated stability studies. A widespread tool to assess the stability of a product through chemical investigations is Fourier Transform Infrared (FT-IR) spectroscopy. Its application guaranties the identification of compounds that are present in a material and the quantitative similarity assessments with other products. The purpose of this master thesis work conducted at Tiss’you regenerative company has been the stability analysis on class III medical devices through chemical investigations with the aim to certify their stability in technical documentations submitted to notified bodies. The studied products have been: Collygen, SpherHA, Sterify gel. The first two devices have been already accepted by notified bodies and they have been real-time studied after 2 years of storing. The last device is the new company proposal and must be still approved. Consequently, accelerated aging protocols have been performed by an external certified company to obtain devices equivalent to 2-years stored products to be analysed. Stability has been examined for all the products with FT-IR spectrometer endowed with Universal Attenuated Total Reflectance (UATR) accessory for solid samples acquisition. However, Sterify gel texture have given first indecisions about the better instrumentation to be used to fulfil such analyses. The High-Performance Liquid Chromatography (HPLC), an analytical technique for the quantification and/or identification of the substances into a solution through a specific chromatogram, have been considered as an alternative to FT-IR spectroscopy. Nevertheless, first trials on HPLC sample preparation soon highlighted the inapplicability of HPLC for Sterify gel stability analyses. The FT-IR acquisitions have been analysed in the instrumentation software where have been obtained correlations between spectra of the aged products (at time 2) and those at time 0. The mean correlations of the aged Collygen and SpherHA with their products at time 0 have been 0.99, while 0.98 for Sterify gel. Therefore, all the devices have been characterized by mean correlations higher than 0.95, threshold to assess stability. Furthermore, a literature-driven peak association testified the presence of characteristic functional groups present in the analysed products. To conclude, the current work certifies the stability of the analysed class III medical devices at time 2. These results will be included in the technical reports submitted to notified bodies. Moreover, Sterify gel stability outcomes encourage future studies aimed at defining its shelf life through further accelerated stability studies