A universal chirality detection platform based on immuno-recognition-driven nanoparticle assembly has been fabricated for the first time. A strong shifted chiral signal was produced by asymmetric plasmonic nanoparticle dimers. Using bisphenol A (BPA) as a model target substrate, the LOD was 0.02 ng mL(-1).

In this work, we report the application of gold nanorods ladder assemblies as chiroptical sensors for detecting mercury ions (Hg(2+)). By taking advantage of the Hg(2+)-mediated T-T base pair of DNA and the high sensitivity of CD measurements, the method offers a simple and sensitive detection of target Hg(2+) residues in water. Therefore, the developed method will be a promising tool for monitoring heavy metal ions, other small molecules and biomacromolecules.

The ability to recognize and quantify the molecular chirality of enantiomers at the nanolevel in biological systems constitutes the basis of many critical areas for specific targeting in drug development and metabolite probing. Plasmonic nanoparticle dimers exhibit circular dichroism effects at visible wavelengths, amplifying the chiral signal of chiral molecules. We demonstrate the self-assembly of plasmonic chiroptical dimers through multibody attractive forces mediated by cysteine, which amplified the plasmonic chirality of enantiomers using enantiomeric cysteines (L and D), and achieved chiral recognition and a quantitative chiroptical sensing platform, with a detection limit of 20 pM level for L-cysteine. The versatility of nanoparticle dimers with customized chiroptical response opens up the avenue for adaptation of the plasmonic chiroptical platform for the drug development and proteomic profiling of metabolites. Results and discussionAs Cys plays a crucial biological role in the human body (e.g. the synthesis of DNA, protein folding, detoxication of cytotoxicity, cell-cell signal transmission, etc. [41][42][43][44][45] ), chiral recognition of Cys