Recent studies analyzed the impact that different sterilization methods have on the elements present in hydroxyethyl cellulose-based gels. The researchers sterilized four samples of gels with a similar basic composition. One sample contained two active pharmaceutical ingredients (APIs)—Chlorhexidine and Lidocaine, two samples contained only one of each of these APIs, while the fourth sample did not contain any APIs.
All the four samples were sterilized with gamma radiation, hot steam, and electron beam methods. For comparison, four different gels were studied and sterilized using gamma radiation, and they were analyzed again with an additional gamma sterilization step.
The study discovered changes in viscosity, rheology, color, odor, as well as the formation of volatile decomposition products in the samples. The stability of the APIs—Chlorhexidine and Lidocaine contained in the three samples was also evaluated. It was observed that the amount of Chlorhexidine and Lidocaine degraded in the first samples. The research did not consider the efficiency of the sterilization methods, but rather, focused on demonstrating the chemical and physical changes occurring due to different sterilization methods and radiation doses.
Radiation, heat, steam, electron or gamma beam are most commonly used sterilization methods. Sterilization should not affect or alter the product, which could otherwise degrade its effectiveness and even harm patients.
Product transformations can be observed by changes in color or the degradation of elements within the formulation. Moreover, radiation can result in the formation of new compounds that might have a toxicological impact on the entire process. The dose of radiation is calculated by the product and the particular type of contaminant as mandated by the International Organization for Standardization (ISO).
In addition to analyzing the impact of sterilization on products, its effects on component materials and packaging must also be considered. Each chemical substance and polymer reacts differently to radiation; therefore, it is crucial to ensure that the given dose does not hamper the product quality of safety throughout its shelf life.