Microfluidic Mixing for Studies of Molecular Self-Assembly
We developed a laminar flow microfluidic mixer that enables real-time monitoring ultrafast kinetics with microsecond resolution for millisecond range. This novel device allows us to investigate molecular conformational change and intermolecular interactions (e.g., protein folding and nanoparticle self-assembly).
We combined the ultrarapid hydrodynamic focusing microfluidic mixer and the time-resolved fluorescence resonance energy transfer measurement to map the very early folding pathway of a protein, cytochrome c, with temporal resolution at microsecond level and structural resolution at Angstrom level (Analytical Chemistry, 2015). In a collaborative project Prof. Benzhong Tan and Prof. Xuhui Huang at HKUST, we used our mixer to dynamically assess the self-assembling process of the aggregation-induced emission (AIE) hexaphenylsilole fluorophore. We probed fluorescence induced by aggregation upon rapid mixing of water and hydrophobic solute and real-time monitored hydrophobic aggregation at microsecond time scale, which allows us to quantify molecular hydrophobic interactions (Nature Communication, 2017).
