DNA origami-mediated plasmonic dimer nanoantenna-based SERS biosensor for ultrasensitive determination of trace diethylstilbestrol

Diethylstilbestrol (DES) is a threatening factor to the human endocrine system. Here, we reported a DNA origami-assembled plasmonic dimer nanoantenna-based surface-enhanced Raman scattering (SERS) biosensor for measuring trace DES in foods. A critical factor influencing the SERS effect is interparticle gap modulation of SERS hotspots with nanometer-scale accuracy. DNA origami technology aims to generate naturally perfect structures with nano-scale precision. Exploiting the specificity of base-pairing and spatial addressability of DNA origami to form plasmonic dimer nanoantenna, the designed SERS biosensor generated electromagnetic-enhancement and uniform-enhancement hotspots to improve sensitivity and uniformity. Owing to their high target-binding affinity, aptamer-functionalized DNA origami biosensors transduced the target recognition into dynamic structural transformations of plasmonic nanoantennas, which were further converted to amplified Raman outputs. A broad linear range from 10−10 to 10−5 M was obtained with the detection limit of 0.217 nM. Our findings demonstrate the utility of aptamer-integrated DNA origami-based biosensors as a promising approach for trace analysis of environmental hazards. [Display omitted] •A DNA origami-based aptasensor targeting diethylstilbestrol (DES) was proposed.•Specificity of base-pairing and spatial addressability of DNA origami were utilized.•The structural transformations of nanoantennas can be converted to Raman outputs.•The biosensor achieved high selectivity and sensitivity sensing with LOD of 0.217 nM.