real-time-force-measurement-between-emulsion-droplets-during

Real-Time Force Measurement Between Emulsion Droplets During Enzymatic Breakdown

This protocol introduces a unique methodology for investigating the stability of emulsions and the dynamic disintegration of emulsion droplets during ...

China Jiliang University

Emulsions stabilized by protein/polysaccharide complexes have attracted great interest. However, the emulsion properties and interactions between droplets at the microscale require further investigation. In this work, the interaction forces between two rice bran oil droplets stabilized by casein-chitosan complexes, with a diameter of 3 ± 0.1 μm (pH 5.54 and no-salt), were measured under different aqueous conditions (pH and ionic strength) using optical tweezers. The measured force curves exhibited consistency with the interfacial layer conformation and interfacial charge, as determined through fluorescence spectroscopy and zeta-potential analysis. Furthermore, atomic force microscopy (AFM) and optical microscopy were employed to characterize the morphology and structural evolution of the emulsions under varying environmental conditions. Our results provide a useful method for studying the interaction forces between Pickering emulsion droplets with pN force resolution and reveal the correlation between interfacial layer properties and physical stability, offering deep insights into the stabilization mechanism of Pickering emulsions.

Measuring interactions between Pickering emulsion droplets coated with casein-chitosan complex using optical tweezers.

Recent research on silver nanowires prepared on DNA templates has focused on two fundamental applications: nano-scale circuits and sensors. Despite their broad potential, the formation kinetics of silver implanted DNA nanowires remains unclear. Here, we present an experimental demonstration of the formation of silver nanowires with a diameter of 2.2 ± 0.4 nm at the single-molecule level through chemical reduction. We conducted equilibrium and perturbation kinetic experiments to measure force during the formation of Ag-DNA complexes and Ag-DNA complexes, using optical tweezers combined with microfluidics. The addition of AgNO resulted in an increase in force of 5.5-7.5 pN within 2 minutes, indicating that Ag compacts the DNA structure. In contrast, the addition of hydroquinone caused the force to decrease by 4-5 pN. Morphological characterization confirmed the presence of a dense structure formed by silver atoms bridging the DNA strands and revealed conformational differences before and after metallization. We compare our experimental data with Brownian dynamics simulations using a coarse-grained double-stranded DNA (dsDNA) model that provides insights into the dependency of the force on the persistence length.

Article	Year
Measuring interactions between Pickering emulsion droplets coated with casein-chitosan complex using optical tweezers. RSC advances\| PubMed ID: 40196823	2025
Dynamics of ultrafine silver implanted DNA nanowire formation. Nanoscale\| PubMed ID: 40548572	2025

Weihong Wang

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