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Unlike in many countries, in the USA, UV filters are treated as drugs and strictly regulated by the Food and Drug Administration. So far, 17 physical and chemical sunscreen agents were approved there to protect against the harmful effects of UV irradiation. In the European Union, access to UV filters is much larger, which gives manufacturers more options to create new sunscreen products in the form of lotions, sprays, oils, creams, gels, pastes, and sticks. Recently, concerns have been raised about the potential unfavorable effects of some UV filters that can penetrate the skin and enter into the systematic circulation. In this study, we prepared oil-in-water emulsions containing two commonly applied sunscreen agents, avobenzone and octyl methoxycinnamate. The formulations were characterized by a high stability at room temperature and a pH in the range of 6.02–6.11. The processes of sunscreen agent release and permeation were performed in a receptor fluid with a pH 5.8 using Strat-M and cellulose membranes to mimic the skin. It was proved that octyl methoxycinnamate exhibited different liberation and permeation patterns than avobenzone, mostly due to its higher lipophilicity. Both processes were also influenced by the type of membrane applied. The liberation of UV filters to the receptor fluid via the cellulose membrane depended on their concentration in the emulsion. As the amount of sunscreen agent in the formulation increases, more of its molecules diffuse to the receiving medium after 48 h. The permeation of the UV filters through the Strat-M membrane occurs at a very low level, 2% for octyl methoxycinnamate and 0.3% for avobenzone, which supports the safety and efficacy of the topical formulations obtained. [ABSTRACT FROM AUTHOR]

In this work, HKUST-1 and Cu-BDC nanoparticles were used as delivery systems for the early anti-COVID-19 drug, hydroxychloroquine. The antiviral MOF/drug combinations significantly reduced the infectivity of SARS-CoV-2, which can be attributed to the nanometric size of the carriers, the presence of copper in the MOF nodes, and the semi-controlled release of the drug. [ABSTRACT FROM AUTHOR]

The present investigation deals with the importance of interaction and position of the nitro group in the adsorptive removal of 2-nitrophenol (2-NP), 4-nitrophenol (4-NP) and phenol by demineralized kraft lignin activated carbon (DKLAAC). The adsorption of phenol and NPs on DKLAAC was found to follow the order 2-NP > 4-NP > phenol. In this study, both solubility and donor–acceptor complex mechanism played an important role besides the porosity and surface area of the materials. Accordingly, the NP possessing the least solubility would noticeably exhibit a higher affinity to be adsorbed at the solid–liquid interface. Thus the highly hydrophobic 2-NP was adsorbed to a greater extent followed by 4-NP and phenol. Moreover, the adsorption capacity as affected by contact time, initial phenol concentration, pH, and temperature was also investigated. The experimental adsorption capacity by DKLAAC was 2.09, 2.34, and 2.20 mmol·g−1 for phenol, 2-NP, and 4-NP at 25 °C, respectively, with the maximum amount being adsorbed within 40 min. The experimental data obtained for the removal of phenol and NPs were adequately fitted by the Langmuir adsorption isotherm and pseudo-second order kinetic models. Additionally, the temperature study revealed the adsorption process to be endothermic and spontaneous with high affinity between DKLAAC and phenols. [ABSTRACT FROM AUTHOR]

The present work aims to provide insight into the role of the functional group in the adsorption of azo dyes namely, ethyl orange (EO), methyl orange (MO), and metanil yellow (MY), on the activated carbon (surface area 569 m2·g−1) prepared from Phyllanthus emblica fruit stone by low-pressure hydrothermal treatment (AC-HTPEFS). More specifically, this study would facilitate a better understanding of the involvement of different amino substituents (-CH3, -C2H5, phenyl group) on the adsorption of azo dye molecules. The experimental adsorption isotherms of the azo dyes quantified with different adsorbents and temperatures (25–45 °C) were utilized to know the effect of functional groups on dye adsorption. Additionally, the equilibrium data were analyzed by applying isotherm models (Freundlich, Langmuir, and Temkin) in order to elucidate the best-fit isotherm model and adsorption capacity, with the Langmuir model fitting the isotherms best as shown by the higher correlation coefficients obtained (0.984–0.994). The Langmuir monolayer adsorption capacities of EO, MO, and MY obtained at 25 °C were found to be 0.202, 0.187, and 0.158 mmol·g−1, respectively, which was attributed to the hydrophobicity and geometry of dye molecules. Moreover, adsorption kinetics conformed well with the pseudo-second-order model. The negative ΔG°, positive ΔH,° and positive ΔS° indicated the adsorption process to be favorable, endothermic, and increased randomness at the solid–liquid interface. Our findings indicate that the porous activated carbon from hydrothermally treated Phyllanthus emblica fruit stone exhibited a promising potential for the removal of azo dyes with rapid kinetics and high adsorption capacity. The present study could thus pave a way for future utilization of activated carbons produced via hydrothermal treatment techniques for wastewater applications. [ABSTRACT FROM AUTHOR]

In the present work, an effort has been made to utilize Phyllanthus emblica (PE) fruit stone as a potential biomaterial for the sustainable remediation of noxious heavy metals viz. Pb(II) and Cd(II) from the aqueous solution using adsorption methodology. Further, to elucidate the adsorption potential of Phyllanthus emblica fruit stone (PEFS), effective parameters, such as contact time, initial metal concentration, temperature, etc., were investigated and optimized using a simple batch adsorption method. It was observed that 80% removal for both the heavy metal ions was carried out within 60 min of contact time at an optimized pH 6. Moreover, the thermodynamic parameters results indicated that the adsorption process in the present study was endothermic, spontaneous, and feasible in nature. The positive value of entropy further reflects the high adsorbent–adsorbate interaction. Thus, based on the findings obtained, it can be concluded that the biosorbent may be considered a potential material for the remediation of these noxious impurities and can further be applied or extrapolated to other impurities. [ABSTRACT FROM AUTHOR]

The outbreak of the coronavirus (SARS‐CoV‐2) pandemic, its rapid spread, and its fatal consequences clearly showed mankind the overwhelming power of nature, and the importance of interdisciplinary research to counter it. Herein, it will be pointed out what challenges arise in fighting nanosized viruses, which feature an outstanding ability to alter their structure and properties to adapt to infection processes, and why nanoscience is extremely powerful to address them. To learn from the past and to be best prepared for the future, this review highlights how the incredible potential of nanoscience can be tapped by mimicking natures' viruses for the development of maximally efficient pharmaceuticals, e.g., COVID‐19 vaccines, by designing preventive and protective equipment, e.g., face masks, as well as developing nanosensors for early detection of infections. [ABSTRACT FROM AUTHOR]