I have to determine concentration of sodium citrate using HPLC method. Previous literature's used potassium phosphate buffer of pH 2.5 as mobile phase (isocratic). As there is risk of clogging the HPLC tubes by using buffer, i would like to know an alternative mobile phase which can be used. Any leads, would be appreciated!
By adding acid to the mobile phase you are converting the citrate anion to citric acid. Try using an 'Acclaim' column or equivalent that are commonly used for organic acid analyse.
By adding acid to the mobile phase you are converting the citrate anion to citric acid. Try using an 'Acclaim' column or equivalent that are commonly used for organic acid analyse.
See attached below.
https://www.phenomenex.com/Application/Detail/14666
You should have no fear in clogging your lines. You can store the column in mobile phase when it is not used over a 'few' days. For a longer period, follow the manufacturer's directions for column storage. NEVER let the column go dry!
When the HPLC is not used (at the end of a run) used HPLC water to flush the tubing. 10x column volumes should be enough (about 100 mL). When the HPLC is switched use the 'new' mobile phase or a miscible solvent to eliminate water (IPA switching to Hexane normal phase)
Bruce Neagle Thank you. I appreciate your input. When i prepare potassium phosphate buffer i am adjusting pH using orthophosphoric acid (85%). Am I right in thinking this would cause conversion of citrate anion to citric acid like you suggest?
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