[Skip to Content](https://www.sigmaaldrich.com#main-content) [](https://www.sigmaaldrich.com/US/en) Products Cart0 USEN Products [Login / Register](https://www.sigmaaldrich.com/oidc-sign-in) [Order Lookup](https://www.sigmaaldrich.com/US/en/order-lookup) [Quick Order](https://www.sigmaaldrich.com/US/en/quick-order) Cart0 [Home](https://www.sigmaaldrich.com/US/en)[Sample Preparation by Filtration](https://www.sigmaaldrich.com/US/en/applications/analytical-chemistry/sample-preparation/filtration)Millicup™-FLEX Disposable Vacuum Filtration Units and Demo Video # Millicup™-FLEX Disposable Vacuum Filtration Units and Demo Video  Millicup™-FLEX disposable vacuum filtration Millicup™-FLEX disposable vacuum filtration units place control in your hands, providing the benefits of traditional glassware with the time-saving flexibility of disposable solutions. - Compatible with organic and aqueous solvents - User-selected, 47 mm membrane filter - Ergonomic, clampless design - Reduced contamination risk - Filter directly into vacuum-rated storage bottles - Easy access to membrane after filtration - Fully recyclable components ## How to use Millicup™-FLEX Filtration Units __Select membrane__ 1. Based on your application and solvent, select the appropriate 47 mm membrane filter. We offer mixed cellulose ester (MCE), polytetrafluoroethylene (PTFE), polycarbonate membrane filters, Millipore Express® PES membranes, and Durapore® PVDF membranes, among other niche membrane filters. __Assemble Millicup™-FLEX filtration unit__ 2. Connect the threaded membrane support collar to a vacuum-rated, receiver bottle by turning in a clockwise manner until the collar is fully tightened, ensuring the gasket remains in place. 3. Using smooth-tip forceps, place a 47 mm membrane disc onto the support collar. 4. Without disturbing the filter, center the base of the funnel on top of the membrane support base and gently press down until you hear an audible “click”. __Connect vacuum source and filter solution__ 5. Attach one of the included tube adapters to the integrated vacuum port, connecting one end of the vacuum tubing to the system and the other end to the vacuum source. 6. Pour sample into funnel and apply vacuum until filtration is complete, rinsing the funnel (if required) while the vacuum is on.  __Remove filtration device and recycle__ 7. Turn off the vacuum and remove tubing. If membrane removal is desired, gently lift up on the funnel for access. 8. Remove the collar by turning in a counter-clockwise manner until loosened. If desired, place a cap onto the receiver bottle for storage. 9. Recycle the filtration unit appropriately. [](https://www.sigmaaldrich.com)[See our complete recycling instructions below](https://www.sigmaaldrich.com#recyclable). ## How to Recycle Millicup™-FLEX Disposable Vacuum Filter Units All three components of the Millicup™-FLEX unit are fully recyclable, minimizing your environmental impact. Before placing the unit in your lab’s mixed plastic or single-stream recycling, you must remove the membrane and rinse any residual solids from the funnel and support collar.  ## Extractables Testing Using Polypropylene Membrane Filters and Millicup™-FLEX Vacuum Filter Units Extractables from consumables, accessories, and apparatuses including filter holders can potentially introduce contaminants that interfere with detection and analysis. We used HPLC, UPLC, and direct infusion mass spectrometry to analyze levels of extractables in Millicup™-FLEX vacuum filtration units. In these studies, 70% acetonitrile was filtered through hydrophilic polypropylene 0.45 µm membrane filters ([PPHH04700](https://www.sigmaaldrich.com/US/en/product/mm/pphh04700)) placed in Millicup™-FLEX devices. No extractables (indicated by contaminant peaks) were observed in any of the methods tested. ## Reusability Testing Using Millicup™-FLEX Vacuum Filter Units We also evaluated the reusability of Millicup™-FLEX devices as described in the previous section. For these analyses, 70% acetonitrile filtered 1X, 5X, 10X, and 20X using the same Millicup™-FLEX funnel and collar. For each filtration step, a new polypropylene membrane filter was used. Three different Millicup™-FLEX devices were tested. Analyses by HPLC, UPLC, and direct infusion mass spectrometry showed similar spectra for each filtration step, with no detectable contaminant peaks. These results suggest that Millicup™-FLEX vacuum filtration units are re-useable for at least twenty HPLC/UPLC mobile phase preparations. Users should always test performance with specific chemicals before re-using the Millicup™-FLEX device. Millicup™-FLEX vacuum filtration units offer reliable filtration in a flexible format compatible with user-selected 47 mm membrane filters. These devices are fully recyclable, reusable, compatible with organic and aqueous solvents, and can be set up quickly in just 20 seconds. With no detectable levels of extractables, Millicup-FLEX™ filter units are suitable for use in high sensitivity filtrate and retentate analyses. ## Millicup™-FLEX Disposable Vacuum Filtration Units Sorry, an unexpected error has occurred Response not successful: Received status code 500 __Related Articles__ - [HPLC Analysis of Polyphenols in Nero d'Avola Red Wine on Discovery® HS C18 (UV 280 nm)](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/analytical-chemistry/filtration/hplc-analysis-of-polyphenols-in-nero-d-avola-red-wine) - [Samplicity® G2 Filtration System](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/analytical-chemistry/filtration/samplicity-in-hplc) - [Qualitative Thin Layer Chromatography Analysis Ginkgo](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/analytical-chemistry/thin-layer-chromatography/qualitative-thin-layer-chromatography-analysis-ginkgo) - [Determination of Caffeine in Coffee Using High Performance Thin Layer Chromatography](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/analytical-chemistry/thin-layer-chromatography/quantification-of-caffeine) - [Determination of Quinine in Tonic Water and Caffeine in Coffee and Cola Drinks Using TLC-MS](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/analytical-chemistry/thin-layer-chromatography/tlc-determination-of-quinine-in-tonic-water-and-caffeine) - [User Guide Dispensing Pressure Vessel Fitting Kit](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/analytical-chemistry/user-guide-dispensing-pressure-vessel-fitting-kit) - [HPLC Analysis of Water-Soluble Vitamins Using Titan C18 Column](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/food-and-beverage-testing-and-manufacturing/water-soluble-vitamins-titan-c18) - [Purification of Serum Peptides for MALDI Mass Spectrometry with Amicon® Ultra Centrifugal Filters](https://www.sigmaaldrich.com/US/en/technical-documents/protocol/protein-biology/protein-mass-spectrometry/purification-of-serum-peptides-for-maldi-mass-spectrometry) - [View More](https://www.sigmaaldrich.com/US/en/search/facet-search?focus=sitecontent&term=facet-search) __Related Product Categories__ - [Laboratory Filter Holders](https://www.sigmaaldrich.com/US/en/products/filtration/laboratory-filter-holders) Top __Sign In To Continue__ To continue reading please sign in or create an account. 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