A simplified fluorescent lateral flow assay for melamine based on aggregation induced emission of gold nanoclusters

A novel lateral flow assay (LFA) was developed based on the aggregation induced emission (AIE) of gold nanoclusters (AuNCs) for the detection of melamine. We compared the interaction between melamine and AuNCs prepared with 6-Aza-2-thiothymine (ATT) and its four structural analogs as ligands and found that the ATTAuNCs showed the best AIE induced by melamine. Then the ATT-AuNCs were directly immobilized on the test line of LFA strips as reporters. The sensing platform exhibited a linear response to melamine from 1 to 100 mu M (R-2 = 0.997) with a detection limit of 217 nM. Moreover, this LFA strip could discriminate 1.0 mu M melamine clearly by the naked eyes within 3 min. The recoveries of 91.6-101.5% were attained in milk and baby formula samples. This strip inherited the superior characteristics of low background interference of aggregation-induced fluorescence recognition and LFA technology, thus effectively avoiding the use of antibodies, aptamers, and other biological elements.

Automated summary

A novel lateral flow assay based on gold nanoclusters with aggregation induced emission was developed for the detection of melamine. The assay exhibited a linear response to melamine with a low detection limit and could differentiate melamine in samples within a short period of time.