Recipe for citrate-phosphate buffer?

[Namjin Chung]

Dear Netters,

I am looking for a recipe for citrate-phosphate buffer which could work 
pH between 3 and 7.  Does anybody know how to make this buffer?  I just 
wondered to make 0.2M citric acid and 0.2M sodium phosphate (mono basic) 
in water.  Is this good?  

Or does anybody know about good buffers working pH range anywhere between 
2 and 4?

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* Namjin Chung                             *                           *
* Program in Molecular Cancer Biology      * Email: nc1 at acpub.duke.edu *
* Duke University Medical Center, Box 3345 * Voice: +1 (919) 684-2363  *
* Durham, NC 27710                         * Fax  : +1 (919) 681-8253  *
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