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Bioburden Reduction and Prefilters for Sterile Filtration

Protect Your Sterile Filters

Prefiltration is a critical process step that extends the life of your more expensive (final) filter by reducing bioburden and removing unwanted particles earlier in the process. The right prefiltration selection must yield the desired product quality as well as be the most efficient and cost-effective solution for your application. Prefilters are recommended in applications where 100% retention of contaminants above a specified pore size is not required. MilliporeSigma offers a wide range of pore sizes and filter formats to meet your prefiltration needs.

Choosing the Right Membrane
  • Milligard® - cellulosic multimedia filters offer the finest prefiltration levels available, providing unsurpassed protection of the final sterilizing filter from premature plugging.
  • Polysep® II - multimedia filters combine borosilicate glass fiber with mixed esters of cellulose to provide higher retention efficiency for more critical degrees of prefiltration.
  • Lifegard™ - borosilicate glass microfiber media filters offer increased adsorptive capacities, ideal for deformable particle retention.
  • Clarigard® - high performance polypropylene depth filters are comprised of fine diameter polypropylene fibers within an optimized graded density structure. The resulting cartridge filter provides superior retention of particulate and bioburden as well as enhanced throughput capacity.
  • Polygard®-CN - polypropylene filters provide high retention efficiency, high flow rates, and high dirt-holding capacity with a melt-blown medium fabricated in a pleated format.
  • Polygard®-CR - polypropylene depth filters offer moderately high retention efficiency, high flow rates, and high dirt-holding capacity by virtue of a graded density of concentrically wrapped media.
  • Polygard®-CT - polypropylene depth filters provide moderate retention efficiency, high flow rates, and high dirt-holding capacity by virtue of their unique density of concentrically wrapped media.

Choosing the Right Format

Cartridge Filters are commonly used for larger processes requiring more filtration area and/or lower unit operating cost. Cartridge filters are used in conjunction with stainless steel housings and can safely withstand multiple steam-in-place cycles. MilliporeSigma cartridge filters are robust, strong, and reliable.

Capsule Filters
  • Opticap® XL disposable capsule filters have a unique design to minimize hold-up volume and reduce production losses and are available in a range of sizes for easy scale-up.
  • Opticap® XLT disposable T-line capsule filters are available with or without a pressure gauge port for ease in monitoring process conditions. The T-line design accommodates series or parallel filtration to match your application needs.
  • Optiscale® disposable capsule filters provide a convenient small-volume option for process development, screening and scaling.

Single-use Redundant Filtration Guide - Learn More

Single-use Redundant
Filtration guide

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Sterile Filter Selector Interactive App - Learn More

Sterile Filter Selector
Interactive app

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