HPLC Analysis of 20 Amino Acids on Amaze SC Mixed-Mode Column in RP and Cation-exchange Modes
Conditions of Experiment
Column: Amaze SC
Separation Modes: reversed-phase cation-exchange
Column Dimenstions: 4.6x250 mm, 5 μm, 100A
Mobile Phase: A: 2% ACN with 0.1% TFA B: 25% ACN with 0.3% TFA from 100% A to 100% B in 20 min, 8 min hold
Detection: Corona CAD
Sample: 0.2 mg/ml
Injection: 5 μL
Flow rate: 1 ml/min
Class of compounds: Amino acid, Neurotransmitter, Supplement
Nature of compounds: Acidic, Hydrophilic, Polar, Zwitterionic
Compounds: Aspartic acid, Serine, Asparagine, Cysteine, Glutamic acid, Threonine, Glutamine, Glycine, Alanine, Proline, Valine, Methionine, Tyrosine, Isoleucine, Leucine, Phenylalanine, Lysine, Histidine, Tryptophan, Arginine
HPLC Analysis of 18 Amino Acids on Amaze HD Column
Conditions of Experiment
Column: Amaze HD
Separation Modes: HILIC, cation-exchange
Column Dimenstions: 3.0x100 mm, 5 um, 100A
Mobile Phase: 80% ACN with 20 mM AmFm pH 3
Detection: ELSD, 45°C
Sample: 0.5-0.8 mg/ml
Injection: 3 uL
Flow rate: 0.6 ml/min
Class of compounds: Amino acid, Catecholamine, Drug, Neurotransmitter, Supplement
Nature of compounds: Acidic, Basic, Hydrophilic, Polar, Zwitterionic
Compounds: Tryptophan, Phenylalanine, Leucine, Methionine, Tyrosine, Isoleucine, DOPA, Valine, Cysteine, Proline, Alanine, Threonine, Glutamic acid, Glycine, Glutamine, Asparagine, Serine, Aspartic acid
HPLC Separation of Underivatized Amino Acids in Buffer-Less Mode on Coresep 100 Core-Shell Mixed-Mode Column
Application description

Amino acids are very polar compounds which are used as a building blocks in pharmaceutical industry. They are widely used as supplements and food additives. Depending on the pH of the mobile phase they can exist in acidic, basic or zwitter-ionic form. At pH below 3, amino acids are basic in nature and have the highest hydrophobicity. Within pH of 3 to 7 amino acids are in zwitter-ionic form where they are the most hydrophilic. There is no mechanism of retention on reversed-phase column and amino acids are not retained. Bufferless ion-separation (BLIS) was introduced by SIELC as a way to retain and analyze amino acids in reversed-phase cation-exchange mode. This mode allows to analyze amino acids as zwitter-ions without any ions/buffers in the mobile phase. The method was adopted for analysis of amino acids on core-shell mixed-mode columns. A similar approach on a reversed-phase core-shell column results in distorted peaks and no separation or significant retention to achieve baseline separation.

Conditions of Experiment
Column: Coresep 100
Separation Modes: reversed-phase and cation-exchange
Column Dimenstions: 3.2 x 50 mm, 2.7 um, 90A
Mobile Phase: 20% ACN with no additives
Detection: UV 205 nm, ELSD
Sample: 0.3 mg/ml
Injection: 1 uL
Flow rate: 1 ml/min
Class of compounds: Amino acid, Supplement
Nature of compounds: Hydrophilic, Polar, Zwitterionic
Compounds: Methionine, Tyrosine, Phenylalanine