Main content area

Synthesis of ficin-protected AuNCs in a droplet-based microreactor for sensing serum ferric ions

Wu, Han, Qiao, Juan, Hwang, Yoon-Ho, Xu, Chengnan, Yu, Tian, Zhang, Rongyue, Cai, Huiwu, Kim, Dong-Pyo, Qi, Li
Talanta 2019 v.200 pp. 547-552
blood serum, calibration, detection limit, ficain, fluorescence, fluorescent dyes, gold, ions, iron, nanogold, wavelengths
A droplet-based microfluidic synthesis approach for preparation of ficin capped gold nano clusters (AuNCs) was developed. Well dispersed AuNCs could be procured within 8 min. Upon excitation wavelength at 340 nm, the resultant AuNCs exhibited a strong blue fluorescence with the maximum emission at 450 nm. Due to the aggregation-induced “turn-off” fluorescence mechanism, the synthesized AuNCs as a fluorescent probe displayed high sensitivity and good selectivity for sensing ferric ions. The relative fluorescence intensity versus ferric ions concentration yielded a good linear calibration in the range of 10.0–1000.0 μM (R2 = 0.998) and the limit of detection was 4.1 μM. Moreover, the possible mechanism for abated fluorescence intensity of AuNCs by adding ferric ions was discussed briefly. Further, the as-prepared fluorescent AuNCs was successfully applied for the detection of serum ferric ions. The results indicated that the droplet-based microfluidic synthesis system could provide a new way for the rapid preparation of AuNCs with good polydispersity and have potential as the sensing probes for the analysis of ferric ions in real biological samples.