Filters and Filtration: A Review of Mechanisms That Impact Cost, Product Quality and Patient Safety

Filters are widely used in the pharmaceutical industry and hospital care for multiple applications such as API processing and purification, pharmaceutical and bio-pharmaceutical operations such as sterile filtration and protein purification, analysis of drug products, while administration to the patients and so on. A multitude of filters with different pore ratings and material of construction are available for use in various applications. The wide variety and type of filters available today also mean that we do not completely understand the nature of such filters and random or un-informed usage could introduce unwanted alterations in the quality or quantity of the product. Thus, one needs to be aware that filters could alter the stability, quality and safety of the product if the right choices are not made. Various mechanisms and examples are described wherein the final quality of the product was affected. Adsorption is the major mechanism of interaction between filters and drug product. Filters can adsorb formulation components such as active pharmaceutical ingredient, preservatives and other excipients which could lead to therapeutic failure or toxicity. Other mechanisms include leaching of filter materials into product during filtration which could adversely affect the product by changing the safety aspect of the product. Despite certain challenges involved while working with filter, usage of filters is the pharmaceutical and biopharmaceutical industry is increasing day by day and many crucial operations such as meeting sterility in aseptic operations, purification of peptides/proteins/Active pharmaceutical ingredients, dissolution analysis etc rely heavily on the quality and right usage of the appropriate filters. It is necessary to minimize the adverse interaction between the filter and the drug product and thus deliver the best to the patient and health care for which the end user needs to thoroughly understand their application, nature of the material being processed and details of the filter to better understand the outcome of the filtration process.