earticle

영어

We report on the development of an efficient optical-sensing platform for the detection of toxic organophosphates using self-assembled peptide nanotubes. Diphenylalanine (Phe-Phe, FF), found in the key motif of Alzheimer’ b-amyloid, was used as a building block to create self-assembled nanotubes that became highly photoluminescent through in-situ incorporation of lanthanide complexes such as salicylic acid/terbium ions or 1,10- phenanthroline/europium ions during the self-assembly process. We found that photoluminescent FF nanotubes underwent a drastic quenching of their emission within a few seconds upon exposure to paraoxon, a nitrofunctionalized neurotoxin. The photoluminescence quenching occurred due to the interruption of cascaded-energy transfer from FF nanotubes to lanthanide ions. The assay platform provided high selectivity toward paraoxon among other organophosphates (e.g., diethylchlorophosphate, dichlorvos, malathion, phosmat), nitro-group compounds (e.g., nitromethane, nitrobenzene, 4-nitrophenol) and common organic chemicals (e.g., alcohols, ethers, ketones, etc.), capability of which was attributed to the role of the FF nanotubes as a host matrix for lanthanide complexes. The peptide nanotube-based optical sensor hints at an alternative route for the selective detection of neurotoxins while avoiding low selectivity, slow response time, and instability of biological receptors in other biosensors.