Mal-PEG-OH (MW 2000) can be used as a macroinitiator to obtain amphiphilic diblock copolymers by ring-opening polymerization of LA. Nanoparticles prepared using amphiphilic block copolymers can form active drug delivery systems. Nanoparticles encapsulate Triptolide (HY-32735), which can avoid the disadvantage of Triptolide’s poor water solubility and reduce its toxicity.