Method for controlling dichloromethane residue in polymer microsphere preparation

The present invention relates to a method for controlling dichloromethane residue in a polymer microsphere preparation. According to the present invention, during a polymer microsphere preparation process, an external leakage bridge solvent is added to a dichloromethane oil phase and/or a water phase, dichloromethane is carried to the water phase during a microsphere curing process through the external leakage bridge solvent, and finally drying is performed, such that dichloromethane residue in the polymer microsphere preparation can be controlled to less than 600 ppm; the method has characteristics of high efficiency, controllability, stable process, safety, and reasonability; and with the method, the problem of dichloromethane residue in the polymer microsphere preparation can be effectively controlled, and complete form, high drug loading, high encapsulation efficiency and good release effect of microspheres can be maintained.