The invention relates to
a DNA nano-molecule
machine for
exosome and
surface protein analysis and application. The
DNA nano-molecule
machine comprises an identification probe generating response to asurface marker of an
exosome, a
signal probe containing two Toehold regions and a fuel probe capable of driving
cycling of a strand displacement reaction. The
exosome is subjected to polyvalent conjugation with a specific
aptamer in the identification probe through the
surface marker of the exosome, so as to release an initiating strand in the identification probe; the initiating strand invades the
signal probe and drives branches of the strand to migrate and release a
quenching strand through being conjugated with a Toehold region I, a
fluorescence reporter group is liberated, and a concealedToehold region II is exposed; and the fuel probe starts up a Toehold-mediated strand displacement cyclic reaction through being conjugated with the Toehold region II, and continuous
branch migrationand polyvalent
recovery occur. Supersensitive quantitative detection on the exosome can be achieved; bi-color or multicolor analysis on two or more kinds of
protein markers on the surface of the exosome can be achieved; and the operation is simple, the consumed time is short, the sample consumption is low, the sensitivity is high, and the specificity is good.