A competitive fluorescence sensor based on AuNPs-β-CD and 1-(4-(1,2,2-triphenylvinyl) phenyl)pyrene for cholesterol detection

A “turn-on” fluorescence sensor was developed for cholesterol detection on the basis of fluorescence resonance energy transfer (FRET) between the organic fluorophore 1-(4-(1,2,2-triphenylvinyl)phenyl)pyrene (TPE-Py) and a gold nanoparticle-β-cyclodextrin conjugate (AuNPs-β-CD). Mechanistically, the AuNPs-β-CD, an energy acceptor, was synthesized via Au–S bonding, and TPE-Py transferred energy to the AuNPs via FRET, resulting in fluorescence quenching of TPE-Py. In the presence of cholesterol, which has a stronger binding affinity for the β-CD cavity, TPE-Py was competitively displaced, enabling the recovery of the fluorescence signal. This sensor has high sensitivity for cholesterol, with a low detection limit of 66 nM and a linear range of 0.5–30 µM. Furthermore, the sensor was successfully used to determine the cholesterol content in food samples with satisfactory recoveries, revealing its potential for food analysis. Section Graphical abstract The alternative text for this image may have been generated using AI.