Self-made frits for nanoscale columns in proteomics

We report here the production of self-made frits for nano-columns. The frits introduce a minor Received: November 24, 2004 dead volume and can be placed in capillaries with a wide range of diameters (20-250 Pm tested) Revised: December 21, 2004 in an extremely simple and low-cost procedure. The obtained columns appear to be comparable Accepted: January 11, 2005 to no-frit columns with near-ideal chromatographic characteristics. We expect that this frit will be useful for the spotting of gradients onto MALDI plates but also where special ESI set-ups do not allow for no-frit solutions.