Water Filtration for Bioprocessing and Pharmaceutical Use

Meet stringent regulatory water requirements by incorporating filtration for added security

Purified Water and WFI 

Critical Process Filtration provides filters for the production of Purified Water (PW) to remove particles left behind by other systems and to reduce or remove bacterial contamination and cell debris.

With water being the most important commodity in bioprocessing and pharmaceutical production, its varied uses (cleaning, ingredient, solvent, excipient, WFI, etc.) require different grades of purity. Filtration can be fine-tuned to achieve the standards of each while helping to reduce costs and even lower water consumption with single-use filters that eliminate the need for device cleaning.

With most systems using Reverse Osmosis (RO) followed by Deionization (DI) to produce purified water, pre- and post-filtration will be required depending on the initial water quality and finished water quality requirements. The generic illustration below represents the many locations in the water purification process where filters play a critical role.

Purified Water _ Water for Injection System Design (Distillation) (5)

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Brochure: Life Science Products

Application Summary: Filtration for Pharmaceutical & Biopharmaceutical Water Systems


Point of Use Filters

To protect against any bacterial contamination that a risk analysis would deem problematic, either bioburden reduction or sterilizing filters would be implemented at point-of-use outlets off the water distribution loop. 

Particle Removal

Filters are implemented throughout PW processes to optimize system performance, prevent unwanted contamination and extend the life of expensive RO/DI and Distillation components. CPF's PPD Filters are constructed with high-purity pleated polypropylene depth media for prefiltering critical water.  These filters have superior retention and protect downstream filters by removing large amounts of particulate.

GDMB and NSPD filters are part of Critical Process Filtration's economical, general-service product line. These filters are used to remove particles from raw water or from treatment steps such as softeners, mixed media beds, or carbon filters. They also remove particles that could prematurely foul the RO system.

Bioburden Control and Sterilizing

Filters can be installed anywhere there is a possibility of bacterial contamination. Your process risk assessment would determine the type and placement of filters. Although a properly functioning RO system should be capable of producing bacteria-free water, the potential for low-level microbial contamination downstream still exists. Reducing bioburden is accomplished with a BPS filter (Polyethersulfone (PES) membrane) or BNM filter (Nylon 6,6).

More often though, water system operators install a CPF SPS, PPS, DPPS, or HPPS 0.22 or 0.10 micron validated PES sterilizing filter after the RO system as an added step of insurance and to optimize water quality. Choosing the correct PES filter will be determined by load burden, flow rate, life expectancy, and system cleaning requirements. For operations requiring nylon media, the PNM sterilizing filter is the best choice.

CPF's PTR filters can prevent environmental and process gas sources of bacteria and contaminants. These hydrophobic sterilizing filters are made with Polytetrafluoroethylene (PTFE) membrane to capture microbial as air/gas enters a tank. 


When keeping endotoxins out of your process is required, they can be eliminated with either of our positively charged endotoxin removal filters. For both sterilization and removing endotoxin, PPC Filters, made with a double layer of PES, is validated for absolute bacteria retention and also capture negatively charged debris. Depending on the level of contaminant and flow rate, PPC filters will typically exhibit > 3-log removal of endotoxin.

If you are already using a sterilizing filter, our general-purpose GPC Filter, made from a single layer of PES, can be added to capture negatively charged biological contaminants.

Quality Assurance and Standards

Critical Process Filtration filters are designed for use in cGMP compliant processes. Our state-of-the-art manufacturing facility and quality-management system both meet ISO 9001:2015 standards. Each operation from assembly and test to cleaning, drying, and packaging is done in appropriately rated clean rooms, and each filter is assigned a lot code to ensure the traceability of manufacturing data and materials. A sophisticated MRP system collects and processes real-time data from manufacturing centers and inspection points. 

USP Biosafety and FDA Compliance

The materials used to construct pharmaceutical-grade filters are non-toxic and meet the requirements for the MEM Elution Cytotoxicity Test and the requirements for Biological Reactivity Tests in the current version of the United States Pharmacopeia (USP) for Class VI - 121 °C Plastics. Critical Process Filtration filters comply with Title 21 CFR sections 210.3 (b)(6) and 211.72, for non-fiber-releasing filters. The levels of bacterial endotoxins in aqueous extracts from pharmaceutical-grade filters are below current USP limits as specified for water for injection.