Syringe filters are single-use, membrane-based devices used for the removal of particulate impurities from liquid and gas samples prior to analysis by methods such as HPLC, ion chromatography, gas chromatography, ICP, and dissolution testing. Proper filtration of samples improves the quality and consistency of analytical results and decreases instrument downtime. Disposable syringe filters are commonly used for fast and efficient filtering. Selection should be by application. Sterile syringe filters are used to sterilize solutions or clarify sterile solutions, while nonsterile syringe filters are used for general filtration and sample purification. Syringe filters are categorized by two essential characteristics – membrane and filter housing. Both characteristics must be compatible with the application and solution being filtered. Syringe filter membranes are matched by composition, filter diameter, and pore size, while syringe filter housings are matched to end applications based on composition and format.
Featuring reduced sample loss due to minimal hold-up volumes, Millex® syringe filters are ideal for use in a variety of applications including HPLC sample preparation, the filtration of antibiotics and tissue culture additives, and dissolution testing. Our controlled manufacturing process ensures reliable filter performance. Our sterile devices include a certificate of quality. Available with many different membrane and housing options, Millex® syringe filters are compatible with a variety of solvents and sample types.
HPLC-certified non-sterile syringe filters are available with nylon, regenerated cellulose or polytetrafluorethylene (PTFE) membranes in polypropylene housing for extra chemical resistance. Sterile tissue culture-tested syringe filters are available in PES, regenerated cellulose, or surfactant-free cellulose acetate membranes in either polypropylene or acrylic copolymer housings. The larger 50 mm diameter disc filter has a PTFE membrane and polypropylene housing with hose barb connectors and is ideal for filtering aggressive solvents or gases and applications requiring sterile venting of gases. Because they have a hydrophobic membrane, they are also ideal for protecting vacuum lines and pumps.
Whatman® Mini-UniPrep® Syringeless Filters provide a faster and easier way to remove particulates from samples being prepared for High Performance Liquid Chromatography (HPLC) and Ultra High Performance Liquid Chromatography (UHPLC) analysis. Mini-UniPrep® is a preassembled filtration device consisting of a 0.4 mL capacity chamber and a plunger. The plunger contains a filtration membrane at one end and a pre-attached cap/septum at the other. The plunger is pressed through the sample in the outer chamber and positive pressure forces the filtrate into the reservoir of the plunger. Air escapes through the vent hole until the locking ring is engaged, providing an air-tight seal. Within seconds the Mini-UniPrep® can be placed into any device able to contain 2 mL vials for injection into your instrument. The Mini-UniPrep® device is designed to fit into any autosampler accommodating 12 x 32 mm vials. Alternatively the septum can be pierced with a needle and the sample drawn off for manual injection into an analyzer. Use with standard robotics on HPLC instruments with sensitive needles, allowing for higher throughput. For use in routine HPLC/UHPLC analysis, composite assays, protein precipitation, solubility testing, dissolution testing, and sample filtration.