Suppressed DNA base pair stacking assembly of gold nanoparticles in an alcoholic solvent for enhanced ochratoxin A detection in Baijiu.

The currently established DNA nanoprobes for the detection of mycotoxin from beverages have been limited by complicated sample pretreatment and uncontrollable nanoparticle flocculation in complex systems. We develop a rapid colorimetric approach for ochratoxin A (OTA) detection in Baijiu in a sample-in/"yes" or "no" answer-out fashion through target-modulated base pair stacking assembly of DNA-functionalized gold nanoparticles (DNA-AuNPs). The colorimetric signification of OTA relies on the competition of OTA with the AuNP surface-grafted DNA in binding with an OTA-targeted aptamer.

SERS-based test strips: Principles, designs and applications.

Test strips represent a class of point-of-care testing (POCT) tools for analysis of a variety of biomarkers towards diagnostics. Conventional test strips offer benefits of simple operation, visualization, and short detection time, along with the drawbacks of relatively low sensitivity and unavailability of quantitative analysis. Recently, the combination of surface-enhanced Raman scattering (SERS) and test strips have evolved to provide a powerful platform capable of ultrasensitive and multiplex detection of extensive analytes of interest.

Opposite Effects of Flexible Single-Stranded DNA Regions and Rigid Loops in DNAzyme on Colloidal Nanoparticle Stability for "Turn-On" Plasmonic Detection of Lead Ions.

Strains in biomolecules greatly restrict their structural flexibility. The effects of DNA's structural flexibility on nanoparticle stability have remained less explored in the field of plasmonic biosensors. In the present study, we discover the opposite effects of a rigid loop and a flexible single-stranded DNA (ssDNA) region in DNAzyme on the colloidal stability of gold nanoparticles (AuNPs), which afford "turn-on" plasmonic detection of Pb.