HPLC is the separation of sample components between the column packing and the mobile phase for mass exchange. Therefore, the mobile phase is required to have the following characteristics:
a. the flow relative to the sample has a certain solubility, to ensure that the sample components will not precipitate in the HPLC column(or remain in the column for a long time).
b. The mobile phase is inert and does not react chemically with the sample (except in special cases).
c. The viscosity of the mobile phase should be as small as possible so that a good separation effect can be obtained when using a longer analytical column; at the same time, the HPLC column pressure drop is reduced and the life of the liquid pump is prolonged (the temperature can be lowered to reduce the viscosity of the mobile phase).
d. The physical and chemical properties of the mobile phase should be compatible with the detector used. If a UV detector is used, it is best to use a solvent with a lower UV absorption.
e. The boiling point of the mobile phase should not be too low, otherwise, bubbles will be easily generated, which may make the experiment impossible.
f. After the mobile phase is prepared, it must be degassed. Removal of traces of gases dissolved in the mobile phase facilitates both the detection and prevention of trace oxygen in the mobile phase from interacting with the sample.
没有评论:
发表评论