Related Experiment Video
Updated: Jan 29, 2026

Fluorescence detection methods for microfluidic droplet platforms
Published on: December 10, 2011
A novel fluorescent sensing platform for insulin detection based on competitive recognition of cationic
Shuang Tan1, Rui Han2, Shilian Wu1
1School of Chemical Science and Technology, Yunnan University, Kunming 650091, PR China.
Abstract:
Competitive host-guest recognition has been utilized to determine small molecules using macrocyclic supramolecular host, while less studies focused on the specific recognition and sensing of protein. In the present work, we are the first time to report a label-free fluorescent assay for insulin determination based on the supramolecular recognition between cationic pillar[6]arene (CP6) and insulin. The approach is based on fluorescence resonance energy transfer (FRET) through competitive recognition between CP6 functionalized reduced graphene oxide (CP6@rGO) and probe/insulin molecules. Probe molecule (RhB) has strong fluorescent signal, and its fluorescent is quenched by rGO based on FRET. When target protein molecule (insulin) is added to CP6@rGO, the probe is displaced by insulin and a host-guest complex CP6@rGO/insulin is formed, resulting in a "turn-on" fluorescence signal. The fluorescence intensity of complex increased linearly with the increase of insulin concentration ranging 0.01-0.50 and 1.0-16.0 μM, respectively with a detection limit of 3 nM. The sensor was successfully utilized to determine insulin in artificial serum. The molecular docking result showed that the N-terminal Phe of insulin's B chain was included in the CP6 cavity through electrostatic interaction and formed a stable host-guest complex.
Related Concept Videos
Competition
The Sense of Self: Reflected Self-Appraisal and Social Comparison
Introduction to Special Senses
Insulin Secretory Vesicles
Tactile and Chemical Senses
Insulin: The Receptor and Signaling Pathways

