Non-destructive evaluation of the medical device packages using the terahertz time-domain spectroscopy

Abstract

Application of the Terahertz time-domain spectroscopy (THz-TDS) in the pharmaceutical industry is well-known, however the Terahertz in the medical device packaging industry for the non-destructive testing application is not yet explored in detail. Polymers such as polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) are commonly used in medical packaging and they are less absorptive in the terahertz regime. Individual-polymer-wrap packages are suitable for single use medical devices such as syringes and needles. The packaging of the medical devices usually takes place in a clean room after undergoing through the sterilization process. It is important to maintain the medical device sterile until it is used. But this type of package is easy to damage during the transportation and (or) the storage. Therefore, it is necessary to monitor the quality of the package continuously to avoid the use of non-sterile medical devices. Terahertz radiation can be used to quickly and non-destructively identify the damaged packages. Because the Terahertz can see through the polymer cover of the medical package and is changed by the humidity within the package. We show that the THz time-domain spectroscopy is able to classify the damaged and the non-damaged individual-warp medical packages. We take the advantage of various water absorption frequency windows from 300 GHz to 1000 GHz to compare the THz-TDS images of the damaged and the non-damaged packages to prove the humidity changes within the package.