Biological applications of kinetics of wetting and spreading

Abstract

Wetting and spreading kinetics of biological fluids has gained a substantial interest recently. The importance of these fluids in our lives has driven the pace of publications. Globally scientists have ever growing interest in understanding wetting phenomena due to its vast applications in biological fluids. It is impractical to review extremely large number of publications in the field of kinetics of complex biological fluids and cosmetic solutions on diverse surfaces. Therefore, biological and cosmetic applications of wetting and spreading dynamics are considered in the following areas: (i) Spreading of Newtonian liquids in the case of non-porous and porous substrates. It is shown that the spreading kinetics of a Newtonian droplet on non-porous and porous substrate can be defined through theoretical relations for droplet base radius on time, which agree well with the experimental results; (ii) Spreading of blood over porous substrates. It is shown that blood, which has a complex non-Newtonian rheology, can be successfully modelled with the help of simple power-law model for shear-thinning non-Newtonian liquids; (iii) Simultaneous spreading and evaporation kinetics of blood. This part enlightens different underlying mechanisms present in the wetting, spreading, evaporation and dried pattern formation of the blood droplets on solid substrates; (iv) Spreading over hair. In this part the wetting of hair tresses by aqueous solutions of two widely used by industry commercially available polymers, AculynTM 22 and AculynTM 33, are discussed. The influence of non-Newtonian rheology of these polymer solutions on the drainage of foams produced from these solutions is also briefly discussed.

Recent progress in the preparation, properties and applications of superhydrophobic nano-based coatings and surfaces: A review

“…Upon wetting, the molecules in the droplet move on the surface of the solid in a manner that can reduce the surface tension. The phenomenon of wetting has various practical applications, [47][48][49][50][51] such as in froth flotation, protection of glue and emulsion, dyeing, construction, insecticides, and parasitoids.…”

Superhydrophobic Self-cleaning Surfaces in Nature

“…Strong interaction between liquid molecules and solid surface, produce surface wetting and liquid spreading over the surface. Wetting occurs at higher surface free energy for different fields including coatings, dyes, anticorrosion and antibacterial applications [29][30][31] . Liquid molecules are attracted to each other's far away from the surface, which indicates the superhydrophobicity with water drops condensed in a spherical shape such as the mercury drops.…”

On the use of a friction model in a Volume of Fluid solver for the simulation of dynamic contact lines

“…The friction coefficient can be determined using the MKT formulation given by relation (3). All the required parameters are given in Qian et al [46].…”

“…Dynamic wetting is encountered in various industrial processes and natural systems [51,3], such as coating [16,24], agrochemical technology [61], printing technology [69], road applications [64] and welding [26]. However, the simulation of moving contact lines is still challenging for numerical simulation.…”