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Updated: Jan 25, 2026

Aqueous Droplets Used as Enzymatic Microreactors and Their Electromagnetic Actuation
Published on: August 28, 2017
Synthesis of ficin-protected AuNCs in a droplet-based microreactor for sensing serum ferric ions
Han Wu1, Juan Qiao2, Yoon-Ho Hwang3
1Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China; School of Chemistry and Chemical Engineering, Xi'an University of Science and Technology, Xi'an 710054, PR China.
Abstract:
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.
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