Accelerated and signal amplified nanozyme-based lateral flow assay of acetamiprid based on bivalent triple helix aptamer

The lateral flow assay (LFA) has received extensive attention and been widely used in various targets. However, the development of aptamer based LFA (Apt-LFA) is still far behind, especially for small molecule targets detection. The shortcoming of long response time severely hindered the Apt-LFA strip application in on-site detection of small molecules contaminants in environment and foods. Herein, we introduce bivalent triple helix aptamer (BTHA) and nanozyme yielding an accelerated and signal amplified LFA for acetamiprid detection. We obtained a BTHA with two 10 nt arms, which could shorten the response time between the aptamer and acetamiprid by 6 times, thus dramatically accelerating the detection of acetamiprid. Moreover, we integrate Au@Pt nanozyme to further amplify the detection signal by catalyzing the color development of substrate. In conjunction with smartphone-based analytical device, the Apt-LFA strip enabled the on-site quantitative detection of acetamiprid residue. It is believed that our strategy will facilitate the development of Apt-LFA against small molecule contaminants.