By Andrea Hilton on Monday, August 2, 2004 - 08:50 am:

I need some help in development of a HPLC method for determination of calcium in calcium phosphate preparations. I have only UV and fluorescende detectors. Is it possible to develop this method?

Thanks.

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By ? on Monday, August 2, 2004 - 06:34 pm:

Have you considered titration?

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By Andrea Hilton on Tuesday, August 3, 2004 - 05:17 am:

I can´t consider titration because it´s for a dissolution profile. Can anyone have any idea? Derivatization?

Thanks

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By judd on Tuesday, August 3, 2004 - 11:30 am:

AA should work easily with this as it's quite sensitive, easy to do, and works well with complex matrices, though you may need to digest the sample. If you don't have access to an Atomic absorption spectrophotometer, contract labs can do the work reasonably economically. Alternately, a good basic AAS isn't enormously expensive, should you be able to justify it of course.

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By ? on Tuesday, August 3, 2004 - 07:49 pm:

There is no reason you cant do a titration. Take a sample at the given time interval and titrate it. It is simple and fast. No one says you have to do a dissolution by LC.

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By bill tindall on Wednesday, August 4, 2004 - 08:33 pm:

I must agree. An EDTA titration for calcium can be done quicker by an experienced chemist than you can load and crimp an autosampler vile and the precision is 10X better.