Chinese medicine chemistry: two-phase solvent extraction operation matters needing attention
in order to help the masses of licensed pharmacists examinee test pass smoothly pass licensed pharmacists, the medical education website small make up to sort out the 'Chinese medicine chemistry: two-phase solvent extraction operation notes' knowledge, relevant content: first, using small tube violent vibration wave about minutes, observe two fluid layer stratification after extraction.
If easy to produce emulsion, a large number of extraction to avoid violent vibration wave, can prolong extraction time.
Such as emulsifying phenomenon, emulsion layer can be separated, then use the new solvent extraction;
Or the emulsion layer suction filter, or heat the emulsion layer slightly;
Or a long time to place does not rotate, make its natural stratification.
Emulsifying phenomenon is serious, can be used in a two-phase solvent reflux extraction plant continuously.
, the concentration of the water extract had better be in proportion.
Between, is too dilute solvent dosage is too large, affect the operation.
, solvent and aqueous solution should maintain a certain amount, the proportion of extraction for the first time, more solvent, and is commonly/water extract, the dosage of the later can be a bit less, general / -
, general extraction -
Time can be.
But hydrophilic hard to turn into larger components organic solvent layer, must increase the extraction times, or change the extraction solvent.