A new independent study demonstrates proprietary pipette filter tips from Porvair Sciences, Wrexham, UK, have greater than 99% bacterial filtration efficiency (BFE) even at an increased challenge level.

The independent test procedure employed was modified from a standard BFE procedure, based upon ASTM F2101, in order to employ a more severe challenge than would be experienced in normal use. 

For the testing, a suspension of Staphylococcus aureus, ATCC #6538, was delivered to the pipette filter tip at a challenge level of greater than 105 colony forming units. The challenge was aerosolized using a nebulizer and delivered to the pipette filter tip under tests at a fixed air pressure and flow rate of 5 liters per minute. The aerosol droplets were generated in a glass aerosol chamber and drawn through the pipette filter tip into all glass impingers for collection. The challenge was delivered for a one-minute interval and sampling through the all-glass impingers was conducted for two minutes to clear the aerosol chamber. Across a sample set of 10 pipette filterstips the testing demonstrated a mean filtration efficiency of 99.36%. All testing was performed in compliance with US FDA good manufacturing practice (GMP) regulations 21 CFR Parts 210, 211 and 820.

Molded from Porvair’s proprietary Vyon porous plastics, the pipette tip filters are fully compliant with FDA, USP Class VI and European Pharmacopoeia statutory regulations as well as being free from heavy metals. The company says the combination of these ultra-clean materials, with excellent porosity properties, has produced a highly reproducible filtered pipette tip with an excellent edge finish that always provides an optimum fit into the pipette tip, enabling labs to routinely achieve superior liquid handling and dispensing. 

For more information, visit Porvair Sciences

Featured image: Porvair Sciences proprietary pipette filter tips have greater than 99% Bacterial Filtration Efficiency. (courtesy Porvair Sciences)