¹H Nuclear magnetic resonance (NMR) relaxometry was exploited to investigate the dynamics of solid proteins. The relaxation experiments were performed at 37 °C over a broad frequency range, from approximately 10 kHz to 40 MHz. Two relaxation contributions to the overall ¹H spin–lattice relaxation were revealed; they were associated with ¹H–¹H and ¹H–¹⁴N magnetic dipole–dipole interactions, respectively. The ¹H–¹H relaxation contribution was interpreted in terms of three dynamical processes occurring on timescales of 10⁻⁶ s, 10⁻⁷ s, and 10⁻⁸ s, respectively. The ¹H–¹⁴N relaxation contribution shows quadrupole relaxation enhancement effects. A thorough analysis of the data was performed revealing similarities in the protein dynamics, despite their different structures. Among several parameters characterizing the protein dynamics and structure (e.g., electric field gradient tensor at the position of ¹⁴N nuclei), the orientation of the ¹H–¹⁴N dipole–dipole axis, with respect to the principal axis system of the electric field gradient, was determined, showing that, for lysozyme, it was considerably different than for the other proteins. Moreover, the validity range of a closed form expression describing the ¹H–¹⁴N relaxation contribution was determined by a comparison with a general approach based on the stochastic Liouville equation.

¹H spin−lattice nuclear magnetic resonance relaxation experiments were performed for five kinds of dermal fillers based on hyaluronic acid. The relaxation data were collected over a broad frequency range between 4 kHz and 40 MHz, at body temperature. Thanks to the frequency range encompassing four orders of magnitude, the dynamics of water confined in the polymeric matrix was revealed. It is demonstrated that translation diffusion of the confined water molecules exhibits a two‐dimensional character and the diffusion process is slower than diffusion in bulk water by 3–4 orders of magnitude. As far as rotational dynamics of the confined water is concerned, it is shown that in all cases there is a water pool characterized by a rotational correlation time of about 4×10⁻⁹ s. In some of the dermal fillers a fraction of the confined water (about 10 %) forms a pool that exhibits considerably slower (by an order of magnitude) rotational dynamics. In addition, the water binding capacity of the dermal fillers was quantitatively compared.

The aim of the work was to quantify the surface wettability of metallic (Fe, Al, Cu, brass) surfaces covered with sprayed paints. Wettability was determined using the contact angle hysteresis approach, where dynamic contact angles (advancing Θ_A and receding Θ_R) were identified with the inclined plate method. The equilibrium, Θ_Y, contact angle hysteresis, CAH = Θ_A − Θ_R, film pressure, Π, surface free energy, γ_SV, works of adhesion, W_A, and spreading, W_S, were considered. Hydrophobic water/solid interactions were exhibited for the treated surfaces with the dispersive term contribution to γ_SV equal to (0.66–0.69). The registered 3D surface roughness profiles allowed the surface roughness and surface heterogeneity effect on wettability to be discussed. The clean metallic surfaces turned out to be of a hydrophilic nature (Θ_Y < 90°) with high γ_SV, heterogeneous, and rough with a large CAH. The surface covering demonstrated the parameters’ evolution, Θ_A↑, Θ_R↑, γ_SV↓, W_A↓, and W_S↓, corresponding to the surface hydrophobization and exhibiting base substratum-specific signatures. The dimensionless roughness fluctuation coefficient, η, was linearly correlated to CAH. The CAH methodology based on the three measurable quantities, Θ_A, Θ_R, and liquid surface tension, γ_LV, can be a useful tool in surface-mediated process studies, such as lubrication, liquid coating, and thermoflow.