Particle clusters at fluid-fluid interfaces: equilibrium profiles, structural mechanics and stability against detachment

Bactericidal action and molecular docking studies of catalytic Cu-doped NiO composited with cellulose nanocrystals

Synthesis of Cu-doped NiO composited with cellulose nanocrystals (CNC) was carried out by co-precipitation method. The aim of this study is to investigate the catalytic, antibacterial and molecular docking studies of prepared samples. XRD patterns confirmed rhombohedral structure of synthesized nanostructures with gradual increase in crystallite size with doping. The morphology as well as interlayer spacing was evaluated with HRTEM while functional groups presence in dopant-free and doped nanostructures was confirmed using FTIR spectra. Both CNC/NiO composite and Cu-doped CNC/NiO showed higher catalytic potential compared to dopant-free NiO, while Cu-doped CNC/NiO nanostructures exhibited significant potential for use in industrial dye degradation applications. Besides this, CNC/NiO composite showed good antibacterial activity against Escherichia coli (E. coli) bacteria and its bacterial activity increased with Cu doping. Furthermore, molecular docking predictions against dihydrofolate reductase and DNA gyrase enzyme confirmed interaction of NiO NPs, CNC/NiO and Cu-doped CNC/NiO inside active pockets and showed good agreement with in vitro bactericidal activity.

Capillary interactions between soft capsules protruding through thin fluid films

When a suspension dries, the suspending fluid evaporates, leaving behind a dry film composed of the suspended particles. During the final stages of drying, the height of the fluid film on the substrate drops below the particle size, inducing local interface deformations that lead to strong capillary interactions among the particles. Although capillary interactions between rigid particles are well studied, much is still to be understood about the behaviour of soft particles and the role of their softness during the final stages of film drying. Here, we use our recently-introduced numerical method that couples a fluid described using the lattice Boltzmann approach to a finite element description of deformable objects to investigate the drying process of a film with suspended soft particles. Our measured menisci deformations and lateral capillary forces, which agree well with previous theoretical and experimental works in case of rigid particles, show that the deformations become smaller with increasing particle softness, resulting in weaker lateral interaction forces. At large interparticle distances, the force approaches that of rigid particles. Finally, we investigate the time dependent formation of particle clusters at the late stages of the film drying.