Structural defects in metal–organic frameworks can be exploited to tune material properties. In the case of UiO-66 material, they may change its nature from hydrophobic to hydrophilic and therefore affect the mechanism of adsorption of polar and non-polar molecules. In this work, we focused on understanding this mechanism during adsorption of molecules with different dipole moments, using the standard volumetric adsorption measurements, IR spectroscopy, DFT + D calculations, and Monte Carlo calculations. Average occupation profiles showed that polar and nonpolar molecules change their preferences for adsorption sites. Hence, defects in the structure can be used to tune the adsorption properties of the MOF as well as to control the position of the adsorbates within the micropores of UiO-66.

Two pyrazoline-based fluorescent and colorimetric probes have been synthesized and their photophysical properties have been investigated by means of electronic absorption and emission spectroscopy. The compounds differ from each other by the presence of a phenyl or thiophene end group attached to the α,β-unsaturated ketone. The probes detect sulphite anions in the Michael addition reaction to the α,β-unsaturated ketone with a high selectivity and good sensitivity (7.56 μM for phenyl and 4.87 μM for the thiophene counterpart). Here, the optical response is based on the recovery of triphenylpyrazoline fluorescence, which is largely blue-shifted as compared to weak charge transfer emission of the sensors. This large hypsochromic shift of the emission maximum along with a strong fluorescence enhancement (up to I^sulphite/I₀ = 43) can be an advantage in terms of the accurate evaluation of the fluorescence intensity ratio. The pyrazoline-based sensor decorated with thiophene is able to detect sulphite species in river water solutions with a good selectivity and sensitivity.

Sonochemical synthesis, driven by acoustic cavitation, has emerged over the past two decades as a powerful and versatile method for producing nanoparticles of bioactive substances with enhanced physicochemical and biological properties. The extreme conditions generated by the collapse of cavitation bubbles - such as transient high temperatures and pressures - facilitate molecular fragmentation, nucleation, and controlled nanoparticle growth. These characteristics make sonochemistry particularly well suited for nanosizing pharmaceuticals, enzymes, and natural bioactive compounds. In addition to a wide range of experimental techniques, recent advances in molecular dynamics simulations have offered critical insights into the molecular-level mechanisms underlying sonochemical processes, revealing the roles of solvent interactions and interfacial dynamics in determining nanoparticle size and stability. This deeper understanding has enabled more precise tuning of synthesis parameters to achieve desired nanoparticle characteristics. Sonochemically synthesized nanoparticles have demonstrated significant potential in diverse biomedical fields, including targeted drug delivery, sonodynamic therapy, regenerative medicine, and antimicrobial coatings. This minireview consolidates two decades of research, highlighting key advancements in the sonochemical synthesis of nanoparticles of bioactive substances, with a focus on molecular-level insights, biomedical applications, future research directions, ongoing challenges, and future perspectives.