How to understand the chromatographic separation? Put it in short, the more similar the separated substance to the stationary phase, the longer the residence time on it. In this way, different substances in a complex mixed solution can be separated according to time, and the separated substances are sequentially entered into the detector to be detected by the detector, and then the scientific researchers can use these detected signals (chromatographic peaks) to calculate the concentration and content of a substance.
To choose the right liquid chromatography column, firstly we should know the packing matrix and its influencing factors.
Packing matrix
1. Silica gel matrix-pH 2-8 —————— At high or low pH, silica gel will dissolve
2. Al2O3. NH2O-pH1-14 ————- Chemical modification is difficult
3. Polymer matrix-pH1-14 ————- Complex pore structure, uneven pore size results in insufficient column efficiency, organic solvents may cause swelling and damage to the polymer matrix.
Packing matrix
1. Silica gel matrix-pH 2-8 —————— At high or low pH, silica gel will dissolve
2. Al2O3. NH2O-pH1-14 ————- Chemical modification is difficult
3. Polymer matrix-pH1-14 ————- Complex pore structure, uneven pore size results in insufficient column efficiency, organic solvents may cause swelling and damage to the polymer matrix.
Influencing factors
1.Physical factors
Purity of silica gel —Purity of filler silica gel and residual metal ion concentration
Column size — length and inner diameter of packed bed
Particle shape —-spherical or irregular
Particle size — average particle diameter
Surface area—the sum of the outer surface of the particle and the inner pore surface, expressed in m2 / gram
Pore size— The average size of the pores or cavities of the particles, ranging from 80-300 & Aring
1.Physical factors
Purity of silica gel —Purity of filler silica gel and residual metal ion concentration
Column size — length and inner diameter of packed bed
Particle shape —-spherical or irregular
Particle size — average particle diameter
Surface area—the sum of the outer surface of the particle and the inner pore surface, expressed in m2 / gram
Pore size— The average size of the pores or cavities of the particles, ranging from 80-300 & Aring
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