It is good practice to filter solvents to prevent pump and other system component damage.

Upchurch Scientific® Inlet Solvent Filters are available in 2, 10, and 20 µm porosities for general use, preparative, and specialized applications. Large surface areas prevent pump cavitation while stainless steel and polymer versions offer chemical compatibility. Special 'Bottom-of-the-Bottle' versions are also available to allow solvent to be drawn to within ¹/₈" (or less) of the bottom of a solvent bottle. For inlet solvent filtering, 10 to 20 µm porosity is usually recommended to filter the mobile phase without causing pump cavitation. If performing helium sparging for solvent degassing, use a 2 µm porosity filter to prevent particulates originating in the sparging system from entering the mobile phase reservoir and to disperse the sparging gas most efficiently. Please note: maximum recommended flow rate is determined by both porosity and surface area of the filter. It is recommended that inlet solvent filters be replaced every six months to one year, depending upon the amount and type of solvent filtered, to ensure proper system performance. All Upchurch Scientific® inlet solvent filters are easy to replace without tools. For those filters using a plastic fitting, the tubing can be reconnected by finger tightening the fitting into the new filter. Filters with stems or ports allow easy tubing press-fit.

General Use Inlet Solvent Filters: these conventional, disposable filters feature 316 stainless steel filter cups and tubing connections via a fitting or stem. Maximum recommended flow rates range from 40 to 100 ml/min.

Stainless Steel Bottom-of-the-Bottle™ Filters: The patented design of these filter assemblies feature a design that allows solvent to be drawn within ¹/₈" (3.2 mm) of the bottom of a solvent bottle. Replaceable 2 or 10 μm stainless steel filter cups allow flow rates of up to 10 ml/min and 40 ml/min, respectively, and are economical to replace. Connect either ¹/₈ or ³/₁₆" Ext.Ø tubing with the provided fitting.

UHMWPE Bottom-of-the-Bottle™ Filters: The design of these biocompatible UHMWPE solvent filters allows tubing to pass through to the bottom of the filter cup, enabling the filter to draw from within 0.10" (2.5 mm) of the bottom of a solvent bottle. The filter cups are replaceable and tubing is connected via the supplied fitting (for ¹/₁₆ or ¹/₈" Ext.Ø tubing). Maximum recommended flow rates for these filters is up to 5 ml/min. Please note: UHMWPE is a hydrophobic material. To establish proper surface wetting, priming of the filter with methanol or acetonitrile may be necessary.

PEEK™ Bottom-of-the-Bottle™ Filters: These highly recommended biocompatible filters are made from 100% PEEK polymer, including two built-in PEEK frits. The bottom frit (2 or 10 μm) will draw solvent from within 0.080" (2.0 mm) of the bottom of a solvent bottle. The 2 μm frit on the side may be used for a ¹/₈" Ext.Ø helium sparging line. Versions for small neck (GL-38) bottles are available. No fittings are required; simply press-fit appropriately sized fluoropolymer tubing firmly into the top holes. Versions for small neck (GL-38) bottles are available. Maximum recommended flow rates for these unique filters is up to 30 ml/min.