Construction And Application Of Luminol Chemiluminescence Sensor Without Additional Oxidant

Chemiluminescence（CL）is a kind of light phenomenon produced by a chemical reaction.The detection method based on this phenomenon is called the chemiluminescence detection method.Compared with other spectral analysis methods（such as fluorescence spectroscopy,UV-Vis spectroscopy,Raman spectroscopy,etc.）,chemiluminescence detection does not require additional light sources and is not affected by background scattered light,so it is applied in many fields.However,traditional luminol chemiluminescence requires adding an oxidant such as hydrogen peroxide（H₂O₂）into the system,which has stability defects due to its easy decomposition.Therefore,this paper is devoted to studying the use of nanoparticles with the activity of oxidase to catalyze the chemiluminescence reaction between luminol and dissolved oxygen,without adding additional oxidants,and then establish a new chemiluminescence detection method,applied to the actual sample detection.The research mainly includes the following two parts:（1）The oxidase-like ferrous disulfide nanoparticles（Fe S₂ NPs）were synthesized,and the glutathione（GSH）sensor based on the ferrous disulfide nanoparticle（Fe S₂NPs）-luminol-manganese dioxide nanoparticle（Mn O₂ NSs）chemiluminescent resonance energy transfer（CRET）system was established.In this system,Fe S₂ NPs with oxidase activity can significantly enhance the CL signal of luminol without the addition of the additional oxidant,while Mn O₂ NSs can quench the CL signal through CRET.When GSH was added into the chemiluminescence system of Fe S₂ NPs-luminol-Mn O₂ NSs,GSH reacted with Mn O₂ NSs to inhibit CRET between luminol and Mn O₂ NSs and restore the CL signal of the system.Therefore,we developed a GSH chemiluminescence sensor based on CRET.Under the optimal conditions,the CL signal of FeS₂ NPs-luminol-MnO₂ NSs system has a good linear relationship with the concentration of GSH in the range of 1-500μM,and the detection limit is as low as0.15μM.The sensor has been successfully applied to the detection of GSH in serum.（2）The oxidase-like copper/silver nanoparticles（Cu/Ag NPs）were synthesized,and the cyanide ion（CN^-）sensor based on the luminol-fluorescein sodium-Cu/Ag NPs system was established,realizing the high sensitivity of CN^-determination.Cu/Ag NPs with oxidase activity can significantly enhance the CL signal of luminol without the need to add additional oxidants.Based on the strong coordination effect of CN^-with Cu²⁺,CN^-interacts with Cu²⁺in the Cu/Ag NPs,reducing the oxidase activity of Cu/Ag NPs,and then quenching the CL signal of luminol-fluorescein sodium-Cu/Ag NPs CRET system.In this system,CN^-concentration and the CL signal of the luminol-fluorescein sodium-Cu/Ag NPs system is a linear relationship with a linear range of0.05-4.00μM and a detection limit of 0.026μM.The sensor has been successfully applied to detect CN^-in tap and lake water.