The invention provides an engineered small
extracellular vesicle as well as a preparation method and application thereof. The preparation method comprises the following steps: S1, removing
cell debris in a sample to obtain supernate; extracting from the supernate to obtain the small
extracellular vesicles; s2, preparing a
phospholipid solution; dissolving the polypeptide A with
Tris. HCl, and then adding the
phospholipid solution for reaction to obtain a coupled polypeptide A
system; taking EDC and sulfo-NHS, then adding
rhodamine polypeptide B and the small
extracellular vesicles, and dissolving the
rhodamine polypeptide B and the small
extracellular vesicles in
tris (
hydroxymethyl) aminomethane
hydrochloride for reaction to obtain a coupled
rhodamine polypeptide B
system; and S3, uniformly mixing the coupled FITC polypeptide A
system and the coupled rhodamine polypeptide B system, and performing
dialysis to obtain the engineered small
extracellular vesicles. The obtained engineered small
extracellular vesicles are stable, can be supplied continuously, can reduce
neurotoxicity effect and relieve the condition of Parkinson's
disease, and provide a new target and a new way for
clinical treatment of Parkinson's
disease.