5-Aminosalicylic acid

Effect of Acid in Mobile Phase on Retention of Neutral, Acidic, Basic and Zwitterionic Compounds on Core-Shell Mixed-Mode Column
Application description

Seven compounds with different properties were used to study an effect of different acids in the mobile phase on retention of neutral, acidic, basic and zwitterionic compounds on core-shell mixed-mode Coresep 100 column. Retention of neutral compounds (propylparaben and benzoic acid to some extent) are not affected by change of the acid. Basic compounds (norphenylephrine, pyridine, 2-aminopyridine) respond the most to change of the strength of acidic additive. Several folds increase in retention time was observed when sulfuric acid was replaced with formic acid in the mobile phase. Effect of acid on retention time of zwitterionic amino acids was less pronounced but still provided excellent retention and peak shape for zwitterionic compounds (5-aminosalicylic acid, phenylalanine). This methods and Coresep 100 column can be used to retain and separate other acidic, basic, neutral and zwitterionic compounds without the use of ion-pairing reagent in the mobile phase. Various detection techniques can be used based on the properties of the mobile phase and analytes. Methods are compatible with mall major detection techniques 9UV, ELSD, CAD, RI, MS). Core-shell mixed-mode columns provide great combination of unique selectivity, speed and efficiency.

Conditions of Experiment
Column: Coresep 100
Separation Modes: reversed-phase, cation-exchange
Column Dimenstions: 4.6 x 150 mm, 2.7 um, 90A
Mobile Phase: 30% ACN with various acids
Detection: UV 255 nm
Sample: 0.3 mg/ml
Injection: 3 uL
Flow rate: 1 mL/min
Analytes
Class of compounds: Amines, Amino acid, Aromatic acid, Aromatic base, Aromatic compound, Catecholamine, Drug, Isomer, Neurotransmitter, Organic acid, Preservative, Pyridine, Supplement
Nature of compounds: Acidic, Basic, Hydrophilic, Hydrophobic, Neutral, Polar, Zwitterionic
Compounds: 5-Aminosalicylic acid, Norphenylephrine, Phenylalanine, Pyridine, Benzoic acid, 2-Aminopyridine, Propylparaben
HPLC Separation of Three Isomers of Aminosalicylic Acid on Coresep 100 Mixed-Mode Column
Application description

Aminosalicylic acids are organic zwitterionic compounds which are hydrophilic in nature. They are very similar in properties and separation of all three isomers is a challenging task. 3-Aminosalicylic, 4-aminosalicylic and 5-aminosalicylic acids were separated on Coresep 100 core-shell mixed-mode column. Mixed-mode chromatography explores a small difference in hydrophobic and ionic properties of molecules to enhance resolution between isomers and other close related compounds. Retention time is controlled by the amount of ACN, buffer concentration, and buffer pH. Method is fast, robust, reproducible, and can be used for analysis of isomers of aminosalicylic acids in various sample matrices. Various mobile phases can be used with Coresep 100 column to accommodate different detection techniques (UV, MS, CAD, ELSD detection). Isomers of other compounds can be retained and separated if they are hydrophobic and basic in nature.Core-shell mixed-mode columns provide а great combination of unique selectivity, speed, and efficiency.

Conditions of Experiment
Column: Coresep 100
Separation Modes: reversed-phase and cation-exchange
Column Dimenstions: 3.0 x 100 mm
Mobile Phase: 20% ACN with 0.1% H3PO4
Detection: UV 275 nm
Sample: 0.3 mg/ml
Injection: 1 uL
Flow rate: 0.6 mL/min
Analytes
Class of compounds: Amino acid, Aromatic compound, Isomer
Nature of compounds: Hydrophilic, Polar, Zwitterionic
Compounds: 3-Aminosalicylic acid, 4-Aminosalicylic acid, 5-Aminosalicylic acid