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1.
Chemosphere ; 338: 139538, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37478995

ABSTRACT

A novel, biomass-derived hybrid sorbent Ban-CD-EPI-Fe was successfully synthesized in a coprecipitation method, in which ß-cyclodextrin copolymerized with banana peel extract and epichlorohydrin was grafted onto an iron oxide surface. The composition, presence of functional groups, morphology, thermal stability, and magnetic properties of the obtained material were characterized by Powder X-Ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy and Energy Dispersive X-Ray Spectroscopy (SEM-EDS), Thermogravimetric Analysis (TGA), and Physical Properties Measurement System (PPMS). The material bearing around 28% of ß-cyclodextrin units has mesoporous structure with plate-like morphology and active surface area determined by BET and Langmuir models equal to 38.35 and 53.59 m2 g-1, respectively. The sorption studies aimed to remove an endocrine disruptor - bisphenol A (BPA), from water. The results showed that the time evolution could be fitted with pseudo-second kinetic order with a rate constant k equal to 0.05 g mg-1 min-1. According to the Langmuir isotherm, a monolayer is created during BPA sorption, and the maximum sorption capacity was estimated as 93.5 mg g-1. After BPA sorption, the hybrid material could be easily separated by an external magnet and regenerated under mild conditions keeping its recyclability in at least eight cycles.


Subject(s)
Water Pollutants, Chemical , beta-Cyclodextrins , Water Pollutants, Chemical/analysis , Adsorption , beta-Cyclodextrins/chemistry , Magnetic Phenomena , Spectroscopy, Fourier Transform Infrared , Kinetics
2.
PLoS One ; 17(12): e0278554, 2022.
Article in English | MEDLINE | ID: mdl-36472972

ABSTRACT

In times of pandemic, health literacy (HL) is very important, as it helps to find, understand, and use essential health information and services. According to WHO, HL is pivotal in fighting infodemic effectively, and education is a vital tool for developing it. In the presented work, we analyze 247 educational materials dedicated to children, adolescents, and their carers explaining the pandemic, prepared by the Chinese, American, German, Italian and Polish governments and international non-governmental organizations. Focusing on the textual and visual side of the documents, we investigated how the pandemic is explained and what discursive measures were used to inform young citizens about the risks and consequences of pandemic restrictions. Additionally, we verified whether the materials helped developing critical thinking, which is crucial to prevent spreading fake news and conspiracy theories. Although the analyzed materials were prepared in different cultural contexts, we identified that all of them contained simple instructions on the desired behaviours during the pandemic. Key messages relating to the importance of hygienic behaviors were often supplemented with guidelines on how to successfully complete each action. While the cultural particularities in presenting the state of the pandemic are visible, the challenges of dealing with the emotional and social crises were dominant all around the world. In our study, we argue that the possibilities of building HL were not fully exploited by the national and international institutions. Citizens were taught how to behave in unusual circumstances but not why they should behave differently. The educational materials lacked reliable knowledge that would allow them to deal with infodemic and develop critical thinking. We conclude that health education expertise worldwide should be focused on enhancing individuals' ability to make informed health decisions and provide three recommendations regarding the process of development of health educational resources for children and the youth.


Subject(s)
COVID-19 , Health Literacy , Swine , Animals , COVID-19/epidemiology , COVID-19/prevention & control , Europe/epidemiology , Health Education , Government
3.
Materials (Basel) ; 14(14)2021 Jul 16.
Article in English | MEDLINE | ID: mdl-34300906

ABSTRACT

Azobenzene derivatives are one of the most important molecular switches for biological and material science applications. Although these systems represent a well-known group of compounds, there remains a need to identify the factors influencing their photochemical properties in order to design azobenzene-based technologies in a rational way. In this contribution, we describe the synthesis and characterization of two novel amides (L1 and L2) containing photoresponsive azobenzene units. The photochemical properties of the obtained compounds were investigated in DMSO by UV-Vis spectrophotometry, as well as 1H NMR spectroscopy, and the obtained results were rationalized via Density Functional Theory (DFT) methods. After irradiation with UV light, both amides underwent trans to cis isomerization, yielding 40% and 22% of the cis isomer of L1 and L2 amides, respectively. Quantum yields of this process were determined as 6.19% and 2.79% for L1 and L2, respectively. The reverse reaction (i.e., cis to trans isomerization) could be achieved after thermal or visible light activation. The analysis of the theoretically determined equilibrium structure of the transition-state connecting cis and trans isomers on the reaction path indicated that the trans-cis interconversion is pursued via the flipping of the substituent, rather than its rotation around the N=N bond. The kinetics of thermal back-reaction and the effect of the presence of the selected ions on the half-life of the cis form were also investigated and discussed. In the case of L1, the presence of fluoride ions sped the thermal relaxation up, whereas the half-life time of cis-L2 was extended in the presence of tested ions.

4.
J Hazard Mater ; 418: 126286, 2021 09 15.
Article in English | MEDLINE | ID: mdl-34098262

ABSTRACT

A novel, bio-derived cyclodextrin-based trifunctional adsorbent has been successfully synthesized for efficient, rapid and simultaneous removal of a broad-spectrum of toxic ionic (anionic and cationic dyes) and non-ionic organic pollutants from water. The composition, morphology and the presence of functional groups in the obtained sorption material were characterized by elemental analysis, XRD, SEM, and FTIR spectroscopy. The adsorption results were represented by cationic dye (crystal violet, CV) and endocrine disrupting compound (bisphenol A, BPA) as an adsorbate. The sorption processes of the model pollutants were studied with both kinetic and equilibrium models. The results showed that the sorption was rapid (less than 1 min) and the time evolution could be fitted using a pseudo-second order model. According to Langmuir isotherm model, the maximum adsorption capacities were found at 113.64 and 43.10 mg g-1 for BPA and CV, respectively. The adsorption ability of ß-CDPs was kept nearly on the same level after five regeneration cycles. Furthermore, almost complete removal of the pollutants was observed during the treatment of real effluents samples thus the bio-derived, cheap and reusable BAN-EPI-CDP has a promising potential for practical applications.


Subject(s)
Cyclodextrins , Environmental Pollutants , Water Pollutants, Chemical , beta-Cyclodextrins , Cations , Cellulose , Polymers , Water , Water Pollutants, Chemical/analysis
5.
Chempluschem ; 85(9): 2067-2083, 2020 09.
Article in English | MEDLINE | ID: mdl-32909681

ABSTRACT

The preparation and characterization of products of the chemical and photochemical rearrangements of a 19-membered o,o'-azoxybenzocrown are presented. In photochemical rearrangement, besides the expected product i. e. 19-membered o-hydroxy-o,o'-azobenzocrown (19-o-OH) obtained under defined conditions with 75 % yield, also other macrocyclic products were isolated and identified, namely: 19-membered p-hydroxy-o,o'-azobenzocrown (19-p-OH), 21-membered o'-hydroxy-o,p'-azobenzocrown (21-o'-OH) and 19-membered macrocycle containing a 5-membered ring bearing an aldehyde group (19-al). The structures of two atypical products of the photochemical rearrangement - 21-o'-OH and 19-al - were determined in the solid state by X-ray analysis and in solution using NMR spectroscopy. Tautomeric equilibrium of the formed hydroxyazobenzocrowns and its change depending on acidity/basicity of the environment and alkali and alkaline earth metal cations complexation were studied using UV-Vis spectrophotometry, spectrofluorimetry and 1 H NMR spectroscopy.

6.
Analyst ; 144(9): 3119-3127, 2019 May 07.
Article in English | MEDLINE | ID: mdl-30924820

ABSTRACT

The synthesis and ion-binding properties of a new amide L derived from 3,4-dihydroxybenzoic acid are described. Due to the presence of a catechol unit, the compound interacts selectively with iron(iii) in organic solvent (dimethyl sulfoxide, DMSO) to produce a color change from pale yellow to green. The incorporation of the ligand L into polymeric matrices or its encapsulation into surfactant-based spheres enables analyte detection in aqueous solutions. The influence of the ligand environment (i.e. organic solvent, polymeric membrane or micelle) on the properties of the sensing materials is analyzed and the sensors are compared.

7.
J Incl Phenom Macrocycl Chem ; 90(3): 189-257, 2018.
Article in English | MEDLINE | ID: mdl-29568230

ABSTRACT

Azobenzene derivatives due to their photo- and electroactive properties are an important group of compounds finding applications in diverse fields. Due to the possibility of controlling the trans-cis isomerization, azo-bearing structures are ideal building blocks for development of e.g. nanomaterials, smart polymers, molecular containers, photoswitches, and sensors. Important role play also macrocyclic compounds well known for their interesting binding properties. In this article selected macrocyclic compounds bearing azo group(s) are comprehensively described. Here, the relationship between compounds' structure and their properties (as e.g. ability to guest complexation, supramolecular structure formation, switching and motion) is reviewed.

8.
J Incl Phenom Macrocycl Chem ; 90(3): 259, 2018.
Article in English | MEDLINE | ID: mdl-31329735

ABSTRACT

[This corrects the article DOI: 10.1007/s10847-017-0779-4.].

9.
Photochem Photobiol Sci ; 16(10): 1570-1579, 2017 Oct 11.
Article in English | MEDLINE | ID: mdl-28884766

ABSTRACT

The synthesis and complexing properties of p-aminoazobenzene-derived mono-, bis-, and trisamides were described. Ligands 3 and 4 bind anions, including fluorides, chlorides, bromides, acetates, benzoates, dihydrogen phosphates, hydrogen sulfates, and p-toluenesulfonates, in chloroform forming 1 : 1 complexes. The highest value of stability constant was evaluated for the 4-F- complex (log K = 5.63 ± 0.21). On the basis of 1H NMR, and FTIR spectroscopy, the possible nature of the ligand-anion interactions was proposed. The E ⇄ Z isomerization process of tripodal amide 4 in chloroform was studied. The effect of anions on Z to E thermal back isomerization was investigated.

10.
J Incl Phenom Macrocycl Chem ; 86(3): 323-335, 2016.
Article in English | MEDLINE | ID: mdl-27881933

ABSTRACT

Novel biscrowns 1 and 2 were synthesized from 13-membered azobenzocrown ethers containing bromoalkylenoxy chains in para position relative to the azo group. The synthesized diester molecules are dodecylmethylmalonic acid derivatives differing by the linker length. The synthesized compounds have the potential of being used as sodium ionophores in ion-selective electrodes. They were characterized and used as ionophores in classic and miniature, solid contact (screen-printed and glassy carbon) membrane ion-selective electrodes. Compound 3, a similar monoester derivative of 13-membered azobenzocrown, was synthesized and used in membrane electrodes for comparison. Lipophilicity of new ionophores was determined by TLC. Lipophilicity of bis(azobenzocrown)s was found to be within the range of logPTLC = 12-13. It was observed that the particularly important selectivity coefficients logKNa,K determined for new electrodes, being logKNa,K = -2.5 and -2.6 (SSM, 0.1 M), are better than those of the electrodes featuring seven out of the nine commercially available sodium ionophores. It was concluded that the ionophore 1 creates, in acetone, with sodium iodide, complex of 1:1 stoichiometry (sandwich complex) with stability constant (logK) ca. 3.0.

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