How to prepare cell cycle test samples correctly?

Cell cycle analysis is a common experimental method in molecular biology, especially in the study of antitumor drugs
All over. But the details are not well handled, and no amount of work can produce a correct, good-looking distribution.
Today, how to prepare the sample of cell cycle test accurately is really a hundred try!
 

A brief introduction to the experimental principle
Propyl iodide (PI) is a nucleic acid dye that binds to DNA and RNA, but it does not penetrate normally
So it has no staining effect on living cells. It can be thinned by the action of cold ethanol or other film breakers
Increased membrane permeability.
After PI enters the cell, it selectively binds to nucleic acid, and after RNase lysis of RNA, the fluorescence of intracellular dyes
The amount of light is proportional to the amount of DNA in the nucleus.
Fluorescence intensity of individual cells was detected by flow cytometry to obtain relative DNA content according to each phase DNA different amounts divide the cells into different cycles.