Molecular switch and application thereof

The invention provides a molecular switch and application thereof, the molecular switch comprises an aptamer sequence, a first linear chain and a second linear chain, the aptamer sequence can bind to a protein to be detected, and the aptamer sequence comprises a repression group at the 3'terminal; the first linear chain sequentially comprises a first sequence, a second sequence and a third sequence from the 5'end, the first sequence comprises a second primer sequence, and the second sequence and the third sequence are complementary with the aptamer sequence and the second linear chain; the 3'end of the second linear chain abuts against the aptamer sequence, the second linear chain sequentially comprises a fourth sequence, a fifth sequence and a sixth sequence from the 5 'end, the fourth sequence and the sixth sequence are complementary with the third sequence and the second sequence respectively, the fifth sequence forms a split ring, and the sixth sequence forms a split ring. The split ...