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Filter paper thickness? - (Nov/25/2010 )

Hi there,

I have been doing some histology and in preparing the solutions for Mallory Trichrome Stain I discovered that the filtration rates for Solution A (1% Acid Fuchsin) and Solution C (2% Orange G, 0.5% Aniline Blue, 2% Oxalic Acid) is excruciatingly slow. I have been using Whatman's filter papers (90mm, Cat No 1001 090), which seems to be fairly standard, but I would really like to order something that's not as thick. Off hand I wasn't able to find any indications of thickness on their online catalogue, so I was wondering if anyone perchance knew an alternative they could recommend.



It depends more on pore size. Whatman's website gives for your filterpaper Grade 1 with 11 Ám (Particle retention in liquid) and a typical thickness of 180 Ám. A filter paper for routine applications with medium retention and flow rate.
If you want a faster one you could use for example grade 591 (Medium fast, thick) or 595 (Medium fast, thin). Those faster papers of course won't have the sample particle retention properties as the one you used, i.e. fine particles might go through the paper. What you need depends finally how fine your particles are and if it is acceptable that some particles might pass through the paper or not. There is a pdf as decision support to pick the right filter paper for your application on the website.
Finally if you need fast and fine filtration, a suction strainer might be useful for you.