1) Based on the Charge of the Stationary Phase
A) Cation Exchange Chromatography
Stationary Phase: Negatively charged groups.
Function: Attracts and exchanges positively charged cations from the solution.
B) Anion Exchange Chromatography
Stationary Phase: Positively charged groups.
Function: Attracts and exchanges negatively charged anions from the solution.
2) Based on the Type of Stationary Phase
A) Gel Type Resins
Structure: Cross-linked polymers with a three-dimensional network.
Examples: Dextrans, agarose.
Features: Porous structure allowing ion exchange.
B) Macroporous or Beaded Resins
Structure: Resins with larger pores and higher surface areas.
Advantages: Increased capacity and faster exchange rates.
3) Based on the Functional Groups Present
A) Strong Acid Resins (SAR)
Functional Groups: Sulfonic acid groups (-SO₃H).
Characteristics: Can exchange all types of cations across a wide pH range.
B) Weak Acid Resins (WAR)
Functional Groups: Carboxylic acid groups (-COOH).
Characteristics: Exchange capacity is pH-dependent.
C) Strong Base Resins (SBR)
Functional Groups: Quaternary ammonium groups.
Characteristics: Can exchange all types of anions.
D) Weak Base Resins (WBR)
Functional Groups: Primary, secondary, or tertiary amine groups.
Characteristics: Exchange capacity for anions is pH-dependent