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By steph89 on Tuesday, July 27, 2004 - 02:10 am:
hello i'm trying to separate methyl paraben and sodium methyl paraben by lc, can anybody help me?
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By tom jupille on Tuesday, July 27, 2004 - 10:54 am:
You have nothing to separate. Methyl paraben and sodium methyl paraben are the same thing in solution. If there is no other source of sodium in your sample, the best you could do would be to analyze the total methyl paraben by LC and the total sodium (by IC or any other technique).
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By Consumer Products Guy on Tuesday, July 27, 2004 - 04:18 pm:
Use water-ACN or water-methanol, with a little acetic acid in the aqueous portion, to force all paraben into its phenolic form, to get total quantitation. Use 280 nm on RP-18 column.
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By A.Mouse on Tuesday, July 27, 2004 - 04:33 pm:
If these are the only two components of your sample, I would take a UV spectrum of both forms, see where the maximum difference is and then see if I can use this for a quantitation of the individual amounts.
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By tom jupille on Wednesday, July 28, 2004 - 09:21 am:
A solution that doesn't involve chromatography? I'm shocked. Shocked!!
hello i'm trying to separate methyl paraben and sodium methyl paraben by lc, can anybody help me?
-------------------------------------------------------------------------------------------------------
By tom jupille on Tuesday, July 27, 2004 - 10:54 am:
You have nothing to separate. Methyl paraben and sodium methyl paraben are the same thing in solution. If there is no other source of sodium in your sample, the best you could do would be to analyze the total methyl paraben by LC and the total sodium (by IC or any other technique).
-------------------------------------------------------------------------------------------------------
By Consumer Products Guy on Tuesday, July 27, 2004 - 04:18 pm:
Use water-ACN or water-methanol, with a little acetic acid in the aqueous portion, to force all paraben into its phenolic form, to get total quantitation. Use 280 nm on RP-18 column.
-------------------------------------------------------------------------------------------------------
By A.Mouse on Tuesday, July 27, 2004 - 04:33 pm:
If these are the only two components of your sample, I would take a UV spectrum of both forms, see where the maximum difference is and then see if I can use this for a quantitation of the individual amounts.
-------------------------------------------------------------------------------------------------------
By tom jupille on Wednesday, July 28, 2004 - 09:21 am:
A solution that doesn't involve chromatography? I'm shocked. Shocked!!
