Magnetically responsive colloidal crystals with angle-independent gradient structural colors in microfluidic droplet arrays
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Updated: Jan 22, 2026
Crystallization and Structural Determination of an Enzyme:Substrate Complex by Serial Crystallography in a Versatile Microfluidic Chip
Published on: March 20, 2021
Junjie Chi1, Changmin Shao2, Yalan Zhang3
1Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, Shenzhen University, Shenzhen 518060, China. ttkong@szu.edu.cn nidong@szu.edu.cn and State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China. yjzhao@seu.edu.cn.
Abstract:
Magnetically responsive colloidal crystal films with gradient structural colors have a significant value in optical applications via controllable external stimuli. Herein, we propose a practical method for fabricating colloidal crystal hydrogel films with continuous gradient structural colors by using superparamagnetic colloidal nanoparticles. The colloidal nanoparticles could self-assemble into chain-like non-close-packed arrays to present structural colors under the stimuli of external magnetic fields. And structural colors with gradient changes could be achieved when subjected to a spatial magnetic field with a remarkable variation in field strength and direction. By integrating with a microfluidic droplet array template with spherical symmetry morphology, we have demonstrated convenient fabrication of free-standing colloidal crystal films with angle-independent gradient structural colors, which could be utilized for the fabrication of optical devices.
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