Construction Of Fluorescence Sensor Arrays And Their Applications In Multi-targets Detection

The development of fast,sensitive,and high throughput detection methods has always been a technical challenge for environmental analysis due to the variety,low concentration,and complex morphological structure of pollutants in water environment.The fluorescence sensor array based on array analysis adopts the sensing mode of artificial simulation of olfactory system,which has the advantages of simultaneous acquisition of multi-channel information and rapid identification of complex samples.It greatly improves the analytical efficiency and detection throughput,and provides a new opportunity for the efficient analysis of pollutants in complex environment.In this paper,four kinds of high efficiency fluorescent sensor arrays were developed for the four kinds of common pollutants:cyanide,heavy metal ions,pesticide residues,and PAHs,which breaks through the limitations of array analysis,such as insufficient quantization ability and difficulty in detecting low chemically active species,and successfully establishes a new method for multitarget simultaneous analysis in complex water environment.The main research includes the following four parts:(1)The ultra-sensitive cyanide fluorescence sensor based on triphenylamine was synthesized,and then cured to cellulose paper to obtain a test paper with significant visual signal changes,combined with color recognition and array analysis,a portable rapid sensitivity detection system was constructed.The detection limit of this strategy was as low as 160 n M,well below the drinking water standards and superior to similar fluorescent sensors.Through the in-depth study of the response mechanism,it was found that the ultra-strong reaction activity of DCV group and the multi-channel signals collection were the main reasons for the ultra-sensitive response of the array.This detection system does not require the use of large instruments,has the advantage of sensitive and portability,and has the potential for on-site detection.(2)A fluorescent sensor array based on polypyridine was developed,and realized the accurate identification and ultra-sensitive quantification of 11 metal ions.The four fluorescent sensors composed of the array exhibited differentiated chelating abilities for different metal ions,providing a variety of multi-channel signal outputs for many heavy metal ions.Combined with multi-channel signal and pattern recognition analysis,11metal ions with similar electronic configuration,affinity and easy mutual interference,such as Fe²⁺,Fe³⁺,Co²⁺,Ni²⁺,Cu²⁺,Zn²⁺,as well as multi-component mixtures of metal ions and binary mixtures of different forms,were accurately detected.The edetection limins were as low as 33.9 n M,which was superior to its peers,and improved the deficiency of the conventional fluorescent sensor array in quantization ability.(3)A multi-channel fluorescent sensor array system composed of three cholinesterase and four thiocholine fluorescent sensors was constructed,which enabled the high-throughput identification of 30 widely used organophosphorus and carbamate pesticides,and allowed the establishment of a brief standard response library with in-class aggregation and dispersion between classes.The database not only enabled the rapid determination of residual categories in actual contaminated samples,but also sensitively quantified a variety of pesticide residues.The detection limits were as low as 16 ppb,well below the maximum allowable concentration in the environment,and obtained results were equivalent to the high-efficiency liquid chromatography.(4)A fluorescent sensor array composed of four kinds of reusable carbon quantum dots/polyvinyl alcohol films with different emission and excitation spectra was developed,and 16 kinds of typical polycyclic aromatic hydrocarbon(PAHs)were accurately and rapidly detected by using fluorescence internal filtering effect.The array system contained 28 signal collection channels,which could provide abundant and differentiated signals for each PAH,ensuring high-throughput identification and sensitive quantification of multiple PAHs.The minimum detection limits were as low as 57 n M,well below the maximum allowable concentration in the environment.The successful construction of the array overcomes the difficulty in detecting such non-chemically active pollutants and expands the application range of the fluorescent sensor array.