Microbial Enumeration | Bioburden Testing

Effortless Membrane Transfer with Microsart®@filter and Microsart®@media

Safeguard patient safety and manufacturing process performance and count the number of microbes in your sample using touch-free membrane transfer to agar.

Assurance that pharmaceutical products are free of microbiological contaminants is a key quality control (QC) requirement for patient safety. Membrane filtration is the regulatory-preferred method for microbial enumeration/bioburden testing (USP <61>, <62> and <1231>, Ph.Eur. 2.6.12, JP 4.05), which quantifies colony-forming units (CFUs) of aerobic mesophilic bacteria and fungi on the agar plate medium. However, transferring the membrane filter to the microbiological medium is one of the most common sources of contamination and false-positive results.

Microsart® filters are ready-to-use sterile filter units that combine a funnel, filter base and gridded membrane filter into a single unit. Microsart® @media dishes are pre-filled with different types of agar medium and sterile packaged. Together, they enable a touch-free membrane transfer that reduces the risk of secondary contamination.

Image of a scientist using Microsart @filters and e.jet pump
Image of a scientist using Microsart @filters and e.jet pump
Microsart® @media
Touch-Free Membrane Transfer

Microsart® @media’s patented adhesive lid transfers the filter and positions it precisely onto the agar plate to allow touch-free transfer of the membrane.

Minimized Risk of Cross-Contamination

The integrated venting function of the new Microsart® Manifold minimizes the risk of cross-contamination during filtration.

Easy Colony Enumeration

Microsart® @media’s convenient, liftable interior lid provides easy access to colonies after incubation.

Choose Your Microsart® @media Type

Media comes sterile packaged, ready-to-use, and pre-filled, according to USP (<61>) and EP (2.6.12).

Choose Your Microsart® @filter Funnel and Membrane Type

Filter base and gridded membrane comes combined with ready-to-use 100 mL or 250 mL funnel.

Easy Connectors Allow Removal Without Cracking

The bayonet closure allows easy adjustments onto - and removal from - the stainless-steel manifold.

Constant Flow Rates Create Sufficient Vacuum with the Microsart@ e.jet pump and Microsart Manifold

Use Microsart® @media and @filter with the Microsart® e.jet transfer pump and Microsart® manifold.

Combine Your Microsart® @media and Microsart® @filter With Optimal Equipment

The fully autoclavable, Microsart® Manifold is made of high-grade stainless steel.

Product Highlights

Microsart e.motion Membrane Filters & & Microsart e.motion Filter Dispenser

Make Membranes Move

Sartorius membrane filters feature the widest selection, three filter colors, two diameters and a variety of pore sizes. The various filter colors and distinctly visible gridlines provide the best contrast with colonies for easy and reliable quantification and identification. The membrane filter band specially designed for the Microsart® e.motion dispenser can be conveniently inserted and easily changed as needed.

  • Membrane filters for colony counting, particle testing and microscopy
  • Outstanding recovery rates for microorganisms
  • Individually sterile-sealed filters are packed on a special pleated band
  • Convenient dispenser enables automatic, touch-free membrane filter dispensing

Microsart® Manifolds

Choose between different sizes of manifolds, from single to multi-branch. The manifold sizes are connectable with each other by quick connection for easy adaptation to daily workload. Depending on the application and criticality of product to be tested, users can choose different funnel and filtration units, from reusable to single sterile solutions.


Tool-free assembly/disassembly facilitates handling, cleaning and sterilization of the manifolds.

Quick connectors on both sides of the manifolds improve usability and allow pump positioning on the left or right side.

Silicone feet prevent the manifold from sliding on the work bench and facilitate overall handling.


The Manifold is made of 100% stainless steel. The high quality of the material (Stainless Steel 316L - 1.4404) and the use of one material type ensures long work life of the manifolds.


Low height ensures efficient and ergonomic operation under the laminar flow, especially when heavy bottles must be repeatedly lifted over the funnel. 

Easy to operate valves minimize the risk of strain injuries when numerous samples must be analyzed in a short period of time. 


Depending on the number of daily tests, users can choose between one, two, three or six-branch manifolds.

The number of filtration positions can be extended easily using the quick connectors. This facilitates adaptation of the installation to the workload. 

Microsart® @Filter PVDF

Do you need to test samples containing aggressive chemicals and adsorptive biological substances like antibiotics for microbial limit testing?

  • We have the answer for quantitative detection of microorganisms in aggressive or difficult-to-filter solutions.

Related Resources

Application Note

Recovery of Burkholderia cepacia Complex Species

Using Microsart® @filter

Access App Note

Article: Bioburden Testing of Viscous Samples

How to Achieve Pharmacopeia-Compliant Bioburden Testing of Viscous Samples

Access the Article

How to Choose a Microbiology Laboratory Pipette

This guide outlines some of the important factors to consider when choosing a manual or electronic pipette for PCR and other microbiological analyses.

Access the Guide

Datasheet: Sterile Single-Use Filtration Units 

Microsart® @Filter units combine the benefits of membrane filtration with the advantages of a ready-to-use filtration unit.

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Datasheet: Microsart® Manifolds 

The filtration stand that adapts to your needs.

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Datasheet: Microsart® e.motion Dispenser 

With the new Microsart® e.motion dispenser, the membrane filters are automatically released from their sterile packaging at the touch of a button, by...

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Datasheet: Microsart® e.jet — Laboratory Transfer Pump with Quick Conn...

New vacuum filtration pump for Microbiological Analysis greatly reduces operating complexity.

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