Basics of Chromatography

• Separation of Analytes

• Type of Equilibrium

M

S

C

CK

Basics of Chromatography

• Ability to dissolve in mobile phase

• Interaction with stationary phase

• Time on X axis• Response on Y

• Chromatography Types

• Separation dependent on time on the column (along with other factors)

• Retention time of the analyte• Retention time of the Mobile Phase

Basics of Chromatography

• Average linear flow rate

• Average linear flow of mobile phase

Rt

L

Mt

L

• Plate Height • Theoretical Measure

of Efficiency

LH

2

• Fig. 26-6• Determining standard deviation from a peak• Std dev = τ W = 4 τ

Basics of Chromatography

• Capacity Factor

• Selectivity Factor

M

SA

V

VKk '

M

MR

t

ttk

'

'

'

A

B

k

k

MAR

MBR

tt

tt

)(

)(

Basics of Chromatography

• The Van Deemter Equation

H = A + B/u + Cu

• Multiple Flow Paths• Tortuosity

• Components of the VanDeemter

• Van Deemter Plot

• How Plate Height is effected by particle size in solid packing

Basics of Chromatography

• Column Efficiency

H

LN

2)(W

tN R

2

2

1

)(54.5W

tN R

Resolution

Basics of Chromatography

• Resolution

W

ttR ARBRS

)()(

The Effect of Mobile Phase on Retention

More on Resolution