In the pharmaceutical industry, the safety, purity, and stability of drugs are directly related to patients’ lives and health. As a core link in the entire pharmaceutical production process, liquid filtration undertakes the important mission of removing impurities, microorganisms, and particulate contaminants. Liquid filter bags have become an indispensable key equipment in liquid processing scenarios of the pharmaceutical industry due to their high filtration precision, stable chemical compatibility, ease of replacement, and compliance with the strict standards of Good Manufacturing Practice (GMP). Starting from the special filtration requirements of the pharmaceutical industry, this article systematically sorts out the core application scenarios, selection key points, and technological development trends of liquid filter bags, providing comprehensive application references for industry practitioners.
I. Core Requirements for Liquid Filtration in the Pharmaceutical Industry: Equal Emphasis on High Purity and Compliance
Pharmaceutical production involves multiple links such as active pharmaceutical ingredient (API) synthesis, preparation manufacturing, injection preparation, and process water treatment. The liquid systems (such as liquid medicines, solvents, buffers, and process water) in each link must meet extremely high purity requirements, which put forward three core demands for filtration equipment:
- Absolute Safety: Filter materials must not undergo chemical reactions with liquid medicines or release extractables (such as heavy metals and organic impurities). At the same time, they must be sterilizable (e.g., withstanding 121°C moist heat sterilization or γ-ray sterilization) to avoid introducing secondary pollution;
- Precise Filtration Precision: According to different drug types (such as oral preparations, injections, and biological products), precise filtration from the micrometer level (e.g., 1-20μm) to the sub-micrometer level (e.g., 0.22μm) must be achieved. Among them, 0.22μm filtration is regarded as a key standard for “sterile filtration”, which can effectively retain microorganisms such as bacteria and fungi;
- Strict Compliance: The production process of filter bags must comply with GMP standards and have a complete quality traceability system (such as material certification and batch test reports). At the same time, they must meet the requirements of international regulatory authorities such as the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) to ensure that drugs can pass the compliance review of the global market.
By using inert polymer materials such as polypropylene (PP), polyester (PE), and polytetrafluoroethylene (PTFE), combined with processes like hot-melt welding and silicone-free sealing, liquid filter bags can fully meet the above requirements and become one of the preferred solutions for liquid filtration in the pharmaceutical industry.
