LAUSR

Spherical nucleic acid probes (SNAPs) are 3D nucleic acid nanostructures with multiple superiorities over bare nucleic acid chains. Au based SNAPs that employ gold nanoparticles (AuNPs) as cores, densely modified nucleic acid chains (commonly via Au-S bond) as shells, have been extensively investigated for the diagnostic and therapeutic of diverse diseases. However, the abundant biothiols in living cells can severely displace the nucleic acid chains from AuNPs and restrict their theranostic performance. Herein, we report the design and preparation of a selenol terminal functionalized molecular beacon (MB-SeH), which was further employed to prepare Au-Se bond-based SNAP (SNAP-Se) for bioimaging. A series of experiments proved the successful preparation of MB-SeH and SNAP-Se, and the obtained nanoprobe could avoid the biothiol interference and eliminate the false positive signals during imaging biomarker in living cells. This work will open a new avenue for the design and application of SNAPs.