Cyclodextrin-based nanosponges (CDNSs) are complex macromolecular structures composed of individual cyclodextrins (CDs) and nanochannels created between cross-linked CD units and cross-linkers. Due to their unique structural and physicochemical properties, CDNSs can possess even more beneficial pharmaceutical features than single CDs. In this comprehensive review, various aspects related to CDNSs are summarized. Particular attention was paid to overviewing structural properties, methods of synthesis, and physicochemical analysis of CDNSs using various analytical methods, such as DLS, PXRD, TGA, DSC, FT-IR, NMR, and phase solubility studies. Also, due to the significant role of CDNSs in pharmaceutical research and industry, aspects such as drug loading, drug release studies, and kinetics profile evaluation of drug–CDNS complexes were carefully reviewed. The aim of this paper is to find the relationships between the physicochemical features and to identify crucial characteristics that are influential for using CDNSs as convenient drug delivery systems.

Bioavailability is the biggest obstacle to the effectiveness of biologically active compounds. Based on a set of physicochemical requirements we can determine if the compound fulfills the drug-like character and if it has the potential to become an active pharmaceutical ingredient (API) with confirmed and thoroughly examined activities. This practice is widely used in drug design of entirely new APIs, but also in search of pharmacological active substances in large compound bases such as plant-derived substances. The chemical structure diversity of plant-based compounds assures that some of them have to be well bioavailable due to good lipid membrane permeability. However, their efficiency is often limited by poor water solubility. Thus, there is a special need for bioenhancers of naturally derived compounds. In this review we present the potential of cyclodextrin nanosponges (CDNSs) as bioavailability enhancers of selected phytochemicals, namely curcumin, resveratrol, oxyresveratrol and quercetin whose very poor water solubility is the biggest obstacle to high efficiency.

Cyclodextrin-based nanosponges (CDNSs) are novel polymers composed of cross-linked cyclodextrin (CD) macrocyclic units, whose characteristics make them great candidates for drug delivery systems with adjustable properties for the drug release process. Examination of the molecular structure and dynamics of CDNSs is a necessary starting point in the first step toward their broad application. Spectroscopic methods are effective analytical tools for probing the structure–property relationships of polymer structures. Infrared (IR) and Raman spectroscopies provide insight into the behavior of hydrogen bond (H-bond) networks influencing the properties of CDNS polymeric networks. Scattering techniques such as inelastic neutron scattering (INS) and Brillouin light scattering (BLS) probe elastic properties, while small-angle neutron scattering (SANS) examines the structural inhomogeneities and water sorption abilities of CDNS materials. Complete evaluation is possible using nuclear magnetic resonance (NMR), which can provide data on CDNS network dynamics. This article summarizes the results of a wide examination of CDNSs with the use of spectroscopic methods and reveals the links between the microscopic behavior and macroscopic properties of CDNSs, enabling the customization of their properties for various biomedical purposes.

Introduction: In order to overpower COVID-19 pandemic a number of security measures have been taken, including limiting of leaving people's place of residence, which is associated with increased social isolation. For students an additional change resulting from the current epidemiological situation is the transition to remote learning which is related with increased time spent in front of a computer or smartphone screen. The aim of the study: The aim of the study was to determine whether the COVID-19 pandemic affects the quality and quantity of sleep in a group of medical students. Materials and methods: Survey search using author-made questionnaire was conducted. Questionnaire included questions about quality and quantity of sleep before and after COVID-19 pandemic outbreak. Collected data was then transformed for statistical purposes and the correlations were examined using Wilcoxon test (before vs after pandemic) or Mann-Whitney U-test (men vs women). Results: Comparing the situation before the pandemic to the present one, statistically significant increase in difficulty in falling asleep in the study group was observed (p=0,008). A statistically significant sleep duration was observed (the mean increased from 7,09 to 7,53, p<<0.05). Students also go to bed later (p<<0.05) and wake up later (p<<0.05). Students also complained about waking up more frequently at night (p=0,006). The respondents rate their current sleep quality worse than before the pandemic (p=0,039). Conclusions: Sleep quality in the group of medical students deteriorated during the pandemic, while the amount of sleep increased. Since the introduction of remote learning, the time of using electronic devices has significantly increased. The obtained results may be used for further research on the impact of the COVID-19 pandemic and remote learning on the quality and quantity of sleep