Maria Merola

Postdoctoral Researcher

Caserta, Italy


PhD Industrial Engineering, Second University of Naples – Foundation of Research and Technology Hellas, Aversa, 2015.
MS Environmental Engineering, Second University of Naples, Aversa, 2012.
BS Civil and Environmental Engineering, Second University of Naples, Aversa, 2010

Research Focus

Viscoelastic properties of corneal epithelial cells with Linear Cell Monolayer Rheometer

Cell mechanics is intrinsically related to cell biological functioning. Telomerase-immortalized human corneal epithelial cells are grown in vitro and their viscoelastic properties are investigated using the Linear Cell Monolayer Rheometer. Through a series of step-strain and stress relaxation measurements, we can determine the time-dependent stress response of the sheared cell monolayer. Moreover, the SkinEthic reconstructed Human Corneal Epithelium is used. The latter is an in vitro multilayer corneal epithelium. It has a columnar basal layer, 2-3 layers of transitional wing cells, and 2-3 layers of superficial squamous cells, and it is shown to secrete mucins found in an in vivo human cornea. We also examine the fundamental parameters of adhesion of contact lenses to corneal epithelial cells and SkinEthic epithelium.

Coalescence inhibition through asphaltene adsorption

Asphaltenes are operatively defined as the crude oil fraction soluble in toluene and not soluble in n-heptane. These surface-active polar macromolecules are responsible for several technical issues during the production, refining and transport of crude oils. For example, during crude oil extraction, transportation and processing phases, they can stabilize water-in-crude oil emulsions by forming a solid-like interface that hinders coalescence and retards film drainage. The separation of water in such emulsions is essential in order to attain adequate export oil quality. Native components of crude oils such as resins, waxes and asphaltenes result to be oil-water interface stabilizers, hindering gravity separation of the oil from the water.
The study of such system is essential from two different points of view: i) industrial: it will contribute for solving technical problems which petrochemical industries are currently facing; ii) scientific: with the aim to bridge colloid chemistry and fluid dynamics.
Using a newly developed apparatus, we performed a study of single water droplet coalescence and film drainage at water/oil interfaces; the oil phase consists of a model oil solution of asphaltenes in toluene. We investigated the influence of aging time on coalescence, where both interfaces (water droplet and water/oil interfaces) are symmetrically aged. In addition, the role of asphaltene concentration in the oil phase is analyzed.

Nanoparticle-surfactant films: coalescence and interfacial rheology

Nanoparticles Surfactants (‘NPSs’) are fascinating systems consisting of nanoparticles dispersed in one liquid phase, and functionalized surface-active polymers, known as ‘ligands’ dispersed in a second, immiscible fluid phase. NPSs are ideal candidates to generate fluid bi-continuous structures, also termed ‘bijels”. Such systems can be achieved by using emulsification processes, mechanical shearing or 3D printing. Subsequent external stimuli can also be used to dynamically reconfigure the spatial distribution of the fluids. Particles and ligands interact at a liquid-liquid (in our case, water-oil) interface to form the NPSs and the assembly of the NPSs results in the formation of a viscoelastic monolayer of NPSs.
We combine Pendant Drop Tensiometry, Interfacial Shear Rheology and Coalescence measurements to investigate the rheology and stability of the NPSs films, with a goal to understand the macroscopic structures that they stabilize.