Herein we describe the development of a homogeneous assay for the detection of 4-nitroaniline(4-NA)and 2,4-dinitroaniline(2,4-diNA).Thisassay relies on fluorescent molecularly imprinted nanoparticles(nano MIPs)which,u...Herein we describe the development of a homogeneous assay for the detection of 4-nitroaniline(4-NA)and 2,4-dinitroaniline(2,4-diNA).Thisassay relies on fluorescent molecularly imprinted nanoparticles(nano MIPs)which,upon interaction with the target analytes,generate areduction in fluorescence emission intensity(quenching).This is due to a resp on sive fluorescent monomer(N-2-propenyl-(5-dimethylamino)-1-naphthalene sulphonamide)employed in the manufacture of the nanoMIPs which,by virtue of the imprinting process,is capable of selectiveinteraction with the target an alyte,thus giving rise to a quenching effect.Selectivity experiments showed excellent recognition propertiestoward the target molecule.Under optimal conditions,the fluorescence intensity of these nano MIPs decreased as the concentration of theimprinted analyte increased from 10 nM to 2.71 pM.A linear relation between the negative logarithm of 4-NA or 2,4-diNA concentrations and the fluorescence intensity for both nanosystems was found(R^2=0.991 and R^2=0.9895),with excellent sensitivity(limit of detection(LOD)=7 and 6 nM,respectively).Furthermore,both nanosystems have been successfully applied for detection of 4-NA or 2,4-diNA in tap water,withrecoveries between 90%to 100.6%and 92%to 100.3%,respectively.Thanks to the versatility of the imprinting process,this nanosystemholds the potential for further development of several optical sensors for many other compounds.展开更多
文摘Herein we describe the development of a homogeneous assay for the detection of 4-nitroaniline(4-NA)and 2,4-dinitroaniline(2,4-diNA).Thisassay relies on fluorescent molecularly imprinted nanoparticles(nano MIPs)which,upon interaction with the target analytes,generate areduction in fluorescence emission intensity(quenching).This is due to a resp on sive fluorescent monomer(N-2-propenyl-(5-dimethylamino)-1-naphthalene sulphonamide)employed in the manufacture of the nanoMIPs which,by virtue of the imprinting process,is capable of selectiveinteraction with the target an alyte,thus giving rise to a quenching effect.Selectivity experiments showed excellent recognition propertiestoward the target molecule.Under optimal conditions,the fluorescence intensity of these nano MIPs decreased as the concentration of theimprinted analyte increased from 10 nM to 2.71 pM.A linear relation between the negative logarithm of 4-NA or 2,4-diNA concentrations and the fluorescence intensity for both nanosystems was found(R^2=0.991 and R^2=0.9895),with excellent sensitivity(limit of detection(LOD)=7 and 6 nM,respectively).Furthermore,both nanosystems have been successfully applied for detection of 4-NA or 2,4-diNA in tap water,withrecoveries between 90%to 100.6%and 92%to 100.3%,respectively.Thanks to the versatility of the imprinting process,this nanosystemholds the potential for further development of several optical sensors for many other compounds.
