ABSTRACT
Hydrogen sulfide (H2S) is a highly toxic environmental pollutant and also an important gaseous transmitter. Therefore, selective detection of H2S is very important, and visual detection of it with the naked eye is preferred in practical applications. In this study, thiolated azido derivates and active esters functionalized gold nanoparticles (AE-AuNPs)-based nanosensors have been successfully prepared for H2S perception. The sensing principle consists of two steps: first, H2S reduces the azide group to a primary amine; second, a cross-linking reaction between the primary amine and active ester induces the aggregation of AuNPs. The AE-AuNPs-based nanosensors show high selectivity toward H2S over other anions and thiols due to the specific azide-H2S chemistry. Under optimal conditions, 0.2 µM H2S is detectable using a UV-vis spectrophotometer, and 4 µM H2S can be easily detected by the naked eye. In addition, the practical application of the designed nanosensors was evaluated with lake water samples.
Subject(s)
Amines/chemistry , Cross-Linking Reagents/chemistry , Esters/chemistry , Gold/chemistry , Hydrogen Sulfide/analysis , Metal Nanoparticles/chemistry , ColorimetryABSTRACT
A series of dual-ligand cofunctionalized fluorescent gold nanodots with similar fluorescence and diverse surface properties has been designed and synthesized to build a protein sensing array. Using this "chemical nose/tongue" strategy, fluorescence response patterns can be obtained on the array and identified via linear discriminant analysis (LDA). Eight proteins have been well distinguished at low concentration (A280 = 0.005) based on this sensor array. The practicability of this sensor array was further validated by high accuracy (100%) examination of 48 unknown protein samples.
Subject(s)
Fluorescent Dyes/chemistry , Gold/chemistry , Luminescent Measurements , Metal Nanoparticles/chemistry , Proteins/analysis , Discriminant Analysis , Models, MolecularABSTRACT
We report a one-pot, two-step strategy to synthesize fluorescent gold nanodots (AuNDs) co-modified with 1-(10-mercaptodecyl)-5-methylpyrimidine-2,4-dione (TSH) and 11-mercaptoundecanoic acid (MUA) through a ligand exchange reaction and demonstrate their capability of selective sulfide sensing in aqueous media on the basis of fluorescence recovery.
Subject(s)
Gold/chemistry , Hydrogen Sulfide/analysis , Metal Nanoparticles/chemistry , Spectrometry, Fluorescence , Fatty Acids/chemistry , Sulfhydryl Compounds/chemistry , Water/chemistryABSTRACT
We developed a novel strategy to prepare functionalized fluorescent gold nanodots (AuNDs) based on a ligand exchange reaction and demonstrated that glutathione modified AuNDs can be utilized for highly sensitive and selective Pb(2+) sensing in aqueous solution.
