Abstract

Several physicochemical methods exist to ensure the safety of biological and biopharmaceutical products in manufacture. Whereas physical methods such as heat and radiation may be used, these are often not viable options owing to detrimental effects on product quality. For example, in the case of products that are heat labile or biochemically complex, these methods may result in alteration of the chemistry or function of the product, or random adsorption of key components. Filtration is the separation of particles from a fluid (liquid or gas) by passage of that fluid through a permeable medium. Sterile filtration ensures complete removal of viable organisms. Advances in membrane technology have resulted in the availability of filtrative devices for the removal of viruses in addition to bacteria. Thus membrane filtration is becoming increasingly the method of choice for sterilization of biologicals, especially when the product is heat labile, because the filtration process in inherently nondestructive.

An overview of the general principles of filtration having specific application to bacterial and viral removal is given herein. The emphasis is on ensuring that the sterility and/or safety of biologicals and biopharmaceuticals be maintained.