Filtration sterilizing equipment

Tests in the sterile work areas includes testing the ventilation system, the filtration systems, equipment surfaces and airborne organisms. 

Processes for adenovirus purification typically end with concentration, formulation, and sterile filtration operations [40, 80,106]. Concentration and formulation are usually carried out in ultra-filtration units equipped with 100-300-kDA membranes [40,106]. The exact composition of the formulation buffer will depend on the intended application, mode of administration (injectable, aerosol), and required short-term and shelf stability [104,123]. A typical liquid formulation may include an aqueous buffer supplemented with cryoprotectants (e.g., sucrose) and stabilizers such as the nonionic-surfactant polysorbate-80, the chelating agent EDTA, and the oxidation inhibitors ethanol and histidine [123]. Filtration under sterile conditions is typically performed with 0.22-pm membranes [103,106]. 

The design of a production facility provides important information regarding whether the facility is intended to produce pharmaceutical grade products or biological weapon grade materials. Relevant design elements include containment, purification equipment, sterilization equipment, and ventilation and filtration systems. 

To reduce risks of microbial contamination, aseptic processing is executed in a controlled environment, in which the air supply, facility, materials, equipment and personnel are regulated to control microbial and particulate contamination to acceptable levels [3]. Contact between product and environment should be minimised, sterile equipment should be used, and there should be two consecutive filtration processes through sterile 0.2 pm filters. The first filter will minimise the microbial challenge to the second filter, which should be just before the sterile final container. The shelf-life of the product is often restricted and it may be stored in the refrigerator to further reduce the risks of microbial growth. 

Adsorption of t-PA to process equipment surfaces consisting of either stainless steel or glass was minimized by adding the detergent polyoxyethylene sorbitan monooleate (Tween 80) to the semm-free culture conditioned media at 0.01% (vol/vol). The equipment was also rinsed, before use, with phosphate buffered saline (PBS) containing 0.01% Tween 80. Hydrophilic, plastic equipment was used whenever possible. AH buffers were sterile filtered. Sterile filtration of Hquids and gases is usually carried out using 0.2 or 0.45 p.m filters. 

The first two categories, clarifying and crossflow filters, have been very well developed and optimized for use in biotechnology and standard wastewater treatment applications. Equipment is easily available for these applications, whether as small 0.2 micron sterilizing filter used to terminally sterilize 100 ml of product solution, or a small 500 ml crossflow filter used to concentrate a small amount of antibody solution. Many vendors of this equipment to wastewater treatment applications have their origins in the CPI (Chemical Process Industries), and have incorporated many of the scale-up and optimization properties developed in much larger units used in large scale chemical production. As a result, these two filtration unit operations are one of the most optimized and efficient used in wastewater treatment. 

This material was made up with distilled water to provide 41 g per liter, and the mixture was adjusted to pH 7.0 with potassium hydroxide solution. To the mixture were added per liter 5.0 g of calcium carbonate and 7.5 ml of soybean oil. 2,000 ml portions of this medium were then added to fermentation vessels, equipped with stirrers and aeration spargers, and sterilized at 121°C for 60 minutes. After cooling the flasks were inoculated with a suspension of strain No. ATCC 11924 of Streptomyces lavendulae, obtained from the surface of agar slants. The flasks were stirred for 4 days at 28°C at approximately 1,700 rpm. At the end of this period the broth was found to contain cycloserine in the amount of about 250 C.D.U./ml of broth. The mycelium was separated from the broth by filtration. The broth had a pH of about 7.5. Tests showed it to be highly active against a variety of microorganisms. 

The USP also recommends the use of biological indicators, whenever possible, to monitor all sterilization methods except sterile filtration. Biological indicators are generally of two types. If a product to be sterilized is a liquid, microorganisms are added directly to carefully identified representative samples of the product. When this is not practical, as with solids or equipment to be sterilized, the culture is added to strips of filter paper. The organism chosen varies with the method of sterilization. 

All production processes, such as ampoule washing and sterilization, solution filtration, equipment set-up and operation, sorting, and freeze-drier cleaning and operation, should be covered in detail in a procedure manual to ensure that all operations are understood as well as carried out properly and uniformly. Cleaning, sterilization, sterile filtration, filling, and aseptic processing operations must be validated. 

Some asceptic processes are developed initially in non-sterile facilities and need to be re-designed to produce a sterile product. Thus the type, size and material used for vessels, piping and tubing (particularly product contact surfaces), the selection of appropriate equipment for each unit process i.e. mixing, filtration, filling, etc., the use of disposable or re-usable equipment, the order of unit operations, the fluid transfer between unit operations and... 

Ready to sterilize) Filling occurs in controlled access rooms (level I, class 100) equipped with vertical flow HEPA filtration at the process steps. HEPA filters are located in the classified area over and around the container in-feed and filling/stoppering equipment. Shrouds are attached to the perimeter of the HEPA filter housing and extend below the equipment work surface to maintain air quality of the critical area (level I, class 100) for the filling lines. 

The stoppers and primary contact filling equipment are transferred from the sterile storage area into a filling room. Eor the filling process, the filtration set-up and filling equipment are aseptically assembled under class 100 conditions in the filling room. 

Use unsterilized medium and filter the medium through the normal sterilizing membrane hooked directly to the filing equipment. The media may be prefiltered to reduce bioburden and increase filtration efficiency. 

Medium for use in a process simulation test can be rendered sterile using either moist heat (autoclaving) or filtration. The method chosen depends on the availability of suitable equipment and the information desired from the study. 

Sweet wines, with potential for yeast refermentation, or wines with potential for malo-lactic fermentation, go through a membrane filtration prior to bottling. The membrane filters come in different porosities 0.65-p, pore size is used most commonly when 100 percent yeast removal is desired, and 0.45-p, pore size is used for malo-lactic bacteria removal. Proper sterilization of bottling equipment downstream of the membrane filter is essential to maintain the yeast- or bacteria-free nature of the wine after filtration. 

If it is thought to be an advantage to increase the activity of the conditioned medium, this may be achieved by concentrating it fourfold using a lOkD molecular weight cut-off membrane. This should be done before the final sterile filtration. There are many types and makes of ultra-filtration equipment available on the market. 

Final product isolation in a form suitable for further processing into the final dose form of the pharmaceutical, e.g., as a tablet or an injectable solution. Secondary production of this type is sometimes done in a separate facility, with the raw material referred to as the bulk product or, more recently, the active pharmaceutical ingredient. Examples of unit operations at this stage of processing include lyophilization, precipitation, or crystallization followed by solid isolation using filtration and drying techniques. In some cases, the final product must be produced in a sterile form, which introduces additional complications when selecting suitable process equipment. 

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