Page 77 - Applied Pharmacognosy
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Evolution of HPLC
Impact of Particle Size Reduction on Resolution
❑ Resolution is increased as a result of using a smaller particle
size. This is due to the increase in the number of theoretical
plates.
HPLC uses high pressure to force LC HPLC
solvent through closed columns
containing fine particles that give
high-resolution separations.
Column Chromatography Particle size μ Pressure
Gravity LC Columns 65 – 200 Gravitational force
Flash LC Columns 40 – 60
Low Pressure LC 40 – 60 2 bar = 30 psi
Medium Pressure LC 25 - 40 ≤ 5 bar = 75 psi
High Pressure LC 5 -20 bar = 100-300 psi
< 10 > 20 bar, > 500 p7s6 i
