Page 147 - Applied Pharmacognosy

Mobile Phase Selection

Guidelines for Setting Mobile Phase Conditions

❑ If the sample is cationic i.e. basic: ion pair reagent is used.

Addition of Sodium Perchlorate

ClO4 Ion pair

50 to 200 mmol/L N +
H

Si Basic substances form ion
O pairs with perchlorate ions,

Si thereby balancing the
charge and increasing the

retention strength.

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