Besides the abuse of well‐known illicit drugs, consumers discovered new synthetic compounds with similar effects but minor alterations in their chemical structure. Originally, these so‐called novel ...psychoactive substances (NPS) have been created to circumvent law of prosecution because of illicit drug abuse. During the past decade, such compounds came up in generations, the most popular compound was a synthetic cathinone derivative named mephedrone. Cathinones are structurally related to amphetamines; to date, more than 120 completely new derivatives have been synthesized and are traded via the Internet. Cathinones possess a chiral center; however, only little is known about the pharmacology of their enantiomers. However, NPS comprise further chiral compound classes such as amphetamine derivatives, ketamines, 2‐(aminopropyl)benzofurans, and phenidines. In continuation of our project, a cheap and easy‐to‐perform chiral capillary zone electrophoresis method for enantioseparation of cathinones presented previously was extended to the aforementioned compound classes. Enantioresolution was achieved by simply adding native β‐cyclodextrin, acetyl‐β‐cyclodextrin, 2‐hydroxypropyl‐β‐cyclodextrin, or carboxymethyl‐β‐cyclodextrin as chiral selector additives to the background electrolyte. Fifty‐one chiral NPS served as analytes mainly purchased from online vendors via the Internet. Using 10 mM of the aforementioned β‐cyclodextrins in a 10 mM sodium phosphate buffer (pH 2.5), overall, 50 of 51 NPS were resolved. However, chiral separation ability of the selectors differed depending on the analyte. Additionally, simultaneous enantioseparations, the determination of enantiomeric migration orders of selected analytes, and a repeatability study were performed successfully. It was proven that all separated NPS were traded as racemic mixtures.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In the past decade, more than 100 different cathinone derivatives slopped over entire Europe due to their enormous popularity. Generally, these novel psychoactive substances are easily available via ...the internet. This fact leads to various social problems, since cathinones are substances with consciousness‐changing effects and are mainly misused for recreational matters by their consumers. Cathinones possess a chiral center including two enantiomeric forms with potentially different pharmacological behavior. This fact makes analytical method development regarding their chiral separation indispensable. In this study, a chiral capillary zone electrophoresis method for the enantioseparation of 61 cathinone and pyrovalerone derivatives was developed by means of four different β‐cyclodextrin derivatives. As chiral selectors, native β‐cyclodextrin as well as three of its derivatives namely acetyl‐β‐cyclodextrin, 2‐hydroxypropyl‐β‐cyclodextrin, and carboxymethyl‐β‐cyclodextrin were used. The cathinone and pyrovalerone derivatives were either purchased in internet stores or seized by police. As a result, overall 58 of 61 studied substances were partially or baseline separated by at least one of the four chiral selectors using 10 mM of β‐cyclodextrin derivative in a 10 mM sodium phosphate buffer (pH 2.5). Furthermore, the method was found to be suitable for simultaneous enantioseparations, for enantiomeric purity checks and to differentiate between positional isomers. Moreover, an intra‐ and an interday validation was performed successfully for each chiral selector to prove the robustness of the method.
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Complexation with cyclodextrins (CDs) has been widely and successfully used in pharmaceutical field, mainly for enhancing solubility, stability and bioavailability of a variety of ...drugs. However, some important drawbacks, including rapid removal from the bloodstream after in vivo administration, or possible replacement, in biological media, of the entrapped drug moieties by other molecules with higher affinity for the CD cavity, can limit the CDs effectiveness as drug carriers. This review is focused on combined strategies simultaneously exploiting CD complexation, and loading of the complexed drug into various colloidal carriers (liposomes, niosomes, polymeric nanoparticles, lipid nanoparticles, nanoemulsions, micelles) which have been investigated as a possible means for circumventing the problems associated with both such carriers, when used separately, and join their relative benefits in a unique delivery system. Several examples of applications have been reported, to illustrate the possible advantages achievable by such a dual strategy, depending on the CD-nanocarrier combination, and mainly resulting in enhanced performance of the delivery system and improved biopharmaceutical properties and therapeutic efficacy of drugs. The major problems and/or drawbacks found in the development of such systems, as well as the (rare) case of failures in achieving the expected improvements have also been highlighted.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Curcumin-β-cyclodextrin complex (Cur-β-CD) was prepared as a novel photosensitizer.•Cur-β-CD generated ROS upon blue light activation.•Cur-β-CD showed desirable bactericidal activity ...against food-borne pathogens.
To overcome the poor water solubility of curcumin, a curcumin-β-cyclodextrin (Cur-β-CD) complex was prepared as a novel photosensitizer. Fourier-transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) were used to verify the formation of Cur-β-CD. Furthermore, the ROS generation capacity and photodynamic bactericidal effect were measured to confirm this Cur-β-CD complex kept photodynamic activity of curcumin. The result showed Cur-β-CD could effectively generate ROS upon blue-light irradiation. The plate count assay demonstrated Cur-β-CD complex possess desirable photodynamic antibacterial effect against food-borne pathogens including Staphylococcus aureus, Listeria monocytogenes and Escherichia coli. The cell morphology determined by scanning electron microscope (SEM) and transmission electron microscope (TEM) showed Cur-β-CD could cause cell deformation, surface collapse and cell structure damage of the bacteria, resulting in the leakage of cytoplasmic; while agarose gel electrophoresis and SDS-PAGE further illustrated the inactivation mechanisms by Cur-β-CD involve bacterial DNA damage and protein degradation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Oxidation of β-cyclodextrin (β-CD) using varying molar ratios of sodium periodate (NaIO4) was investigated in detail on synthesis, characterization and antibacterial property. Synthesis and ...characterization results showed that Oxidized β-cyclodextrins (OX-β-CDs) were obtained and aldehyde (CHO) groups were successfully introduced. Our results demonstrated that aldehyde content and yield increased with increasing NaIO4 molar amount. However, the structure of β-CD was degraded as a result of glycosidic ring opening with increasing stoichiometric ratio of NaIO4/β-CD to 5/1 and 7/1.
Aldehyde functional groups in OX-β-CDs were characterized by employing FTIR, 1H NMR, XRD, SEM techniques and confirmed by the detection of CHO peak at 1730 cm-1 in the FTIR and detection of the aldehyde H peak between 9 to 10 ppm in the 1H NMR spectrum. In addition, SEM and XRD of OX-β-CDs showed alterations in the morphological and crystal structure (transforming from crystalline to amorphous) of β-CD as a result of increasing oxidation.
Especially, antibacterial activity of OX-β-CDs was investigated against both Gram-negative and Gram-positive bacteria by using the minimal inhibitory concentration (MIC) and the Disk diffusion method. The results showed that OX-β-CDs possessed good antibacterial activity, which can destroy the bacterial cell wall, and may be used as an antibacterial agent.
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•Oxidized β-cyclodextrin was synthesized with various amount of sodium periodate.•Aldehyde functional groups were introduced into β-cyclodextrin unit.•Oxidation degree has a big influence on the structural integrity of the molecule.•There were changes in the cyclic structure of some Oxidized β-cyclodextrins.•Oxidized β-cyclodextrins possessed a quite good antimicrobial activity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
As one of the essential components in electrodes, the binder affects the performance of a rechargeable battery. By modifying β‐cyclodextrin (β‐CD), an appropriate binder for sulfur composite cathodes ...is identified. Through a partial oxidation reaction in H2O2 solution, β‐CD is successfully modified to carbonyl‐β‐cyclodextrin (C‐β‐CD), which exhibits a water solubility ca. 100 times that of β‐CD at room temperature. C‐β‐CD possesses the typical properties of an aqueous binder: strong bonding strength, high solubility in water, moderate viscosity, and wide electrochemical windows. Sulfur composite cathodes with C‐β‐CD as the binder demonstrate a high reversible capacity of 694.2 mA h g(composite)−1 and 1542.7 mA h g(sulfur)−1, with a sulfur utilization approaching 92.2%. The discharge capacity remains at 1456 mA h g(sulfur)−1 after 50 cycles, which is much higher than that of the cathode with unmodified β‐CD as binder. Combined with its low cost and environmental benignity, C‐β‐CD is a promising binder for sulfur cathodes in rechargeable lithium batteries with high electrochemical performance.
The sulfur utilization and cycling stability of composite cathodes in rechargeable lithium batteries are enhanced by carbonyl‐β‐cyclodextrin (C‐β‐CD) as the binder in sulfur composite cathodes. This is made possible by the fact that C‐β‐CD is highly soluble in water, ca. 100 times more soluble than β‐CD at room temperature, and because it exhibits strong bonding strength.
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•β-CD and Fe3O4 were combined for modifying HC to prepare β-CD@MHC.•β-CD@MHC possessed excellent uptake of 47.28 mg/g for Cd(II) and 60.27 mg/g for ANT.•Different adsorption ...mechanisms for Cd(II)/ANT averted adsorption sites competitions.•Applying an external magnetic field could easily separate β-CD@MHC from water.•High desorption efficiency guaranteed repeated use of β-CD@MHC.
Magnetic hydrochar modified by β-cyclodextrin (β-CD) described as β-CD@MHC was successfully synthesized and applied to simultaneous removal of cadmium (Cd) and anthracene (ANT). Characterizations attested the grafting of β-CD groups onto β-CD@MHC with excellent magnetism. Moreover, the β-CD@MHC could eliminate Cd(II) and ANT during an extensive pH scope, and presented fast adsorption equilibrium in 60 min and 80 min for Cd(II) and ANT, respectively. And the β-CD@MHC possessed prominent adsorption properties with maximum monolayer binding of 47.28 mg/g for Cd(II), and corresponding heterogeneous uptake of 60.27 mg/g concerning ANT. Furthermore, the β-CD@MHC could effectively avoid the competitive behavior between Cd(II) and ANT mainly due to complexation and electrostatic attraction effects for capturing Cd(II), and host–guest interaction in the removal of ANT. Additionally, the binding of Cd(II) and ANT onto β-CD@MHC dropped slightly after stepwise desorption, suggesting the β-CD@MHC as a high-performance adsorbent for heavy metals and PAHs elimination from wastewater.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Efficient strategy to down-size zeolite crystal to 50–100 nm.•Higher specific surface area and pore volume than conventional zeolite.•Enhanced adsorption capacity and separation ...performance.•Boosted diffusion and mass transfer rate.
Down-sizing zeolite crystals to achieve enhanced gas adsorption and separation performances is largely unexplored and underestimated. Nano-sized zeolite can expose more adsorption sites and shorten the diffusion path compared to micro-sized counterparts; however, the synthesis of Nano-sized zeolite is still very challenging. Herein, nano-sized ZK-5 is successfully prepared for the first time via the regulation effects of β-cyclodextrin. The crystal size of ZK-5 can be reduced from micron-size (3 μm) to nano-size (50–100 nm), thus the nano-ZK-5 exhibits a superior surface area (370 cm2 g−1) and pore volume (0.22 cm3 g−1) than the micron-sized sample (149 cm2 g−1 and 0.07 cm3 g−1), which may be due to the reduction in crystal size, which in turn leads to more micropores being detected. The CH4 adsorption capacity on nano-sized sample increased by 64% compared to that of micron-sized ZK-5. Notably, the record-high CH4 adsorption capacity of 1.34 mmol g−1 at 298 K is obtained on the nano-ZK-5 among the commercial zeolites. The equilibrium adsorption selectivity of CH4/N2 (20/80, v/v) mixed gas is as high as 4.2 (IAST method) at 1 bar and 298 K. The adsorption kinetics experiments have illustrated the boosted gas diffusion and mass transfer rate. Furthermore, the breakthrough experiments have confirmed the practical feasibility of separating various gas-mixtures, such as CH4/N2 (20/80, v/v).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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