(http://www.fishersci.com/wps/portal/PRODUCTDETAIL?productId=610584&catalogId=29101&pos=1&catCode=SE_SC&fromCat=yes&keepSessionSearchOutPut=true&brCategoryId=null&hlpi=y&fromSearch=Y). In North America the main manufacturer (I think) is Whatman, possible to order through Fisher (the link above). Just be sure they are binder-free, and if you don't care about measuring carbonates, the best preservation is by acidifying with 6N HCl (100 uL for 30 mL water is what works for the St. Lawrence river- 3 years and counting!). We also combust them at 500 degC for a few hours to ensure no contamination with soluble organics.

On Thu, Apr 2, 2009 at 1:51 PM, Gurumurthy G P <gurumurthy.gp@manipal.edu> wrote:

Dear all members,

Greetings from Manipal, India

Could you please suggest me which membrane filter are preferable for measuring dissolved organic carbon in river water???? I would appreciate if you direct me to website of suppliers.

Anticipated thanks

Yours sincerely

Gurumurthy G P

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Gurumurthy G P - Junior Research Fellow, Department of Civil Engineering,

Manipal Institute of Technology, Manipal University, Manipal 576 104. INDIA

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