How can i adjust the pH 4.4 for the mixture of K2HPO4, KH2PO4, CITRIC ACID, TRIETHYL AMINE ?
usually I use H3PO4 to adjust for the above but some people will use HCl . is HCl be used for the adjustment
Mobile phase buffer can be made from a mixture of an acid/base and its conjugate base/acid.
It is normal to use the conjugate acid in order to adjust the pH of your mobile phase. It is phosphoric acid in your case since you have both hydrogen phosphates as your conjugate bases. Just add phosphoric acid dropwise to your mobile phase while stirring until you reach a pH of 4.4 (shouldn't take much).
It is better to use phosphoric acid ( as conjugate acid to K2HPO4 and KH2PO4 ) to adjust pH to 4.4, and to minimize the different ions in the final solution.
Dear Sudhakara Rao Saidam,
I agree with PS Biotech. As you heard from others, HCl will change pH quicker and with less amount. But you must be sure that Cl(-) ion, which will be added to your mobile phase, will have no effect on your system. Thank You and Good Luck
- Badges
- Science method
- Similar topics
- Chemistry
- General Biochemistry
- Biochemical Techniques
- Analytical Chemistry