Magnetic Β-cyclodextrin Research Articles

Solvent and monomer regulation synthesis of core-shelled magnetic β-cyclodextrin microporous organic network for efficient extraction of estrogens in biological samples prior to HPLC analysis

The abnormal estrogens levels in human body can cause many side effects and diseases, but the quantitative detection of the trace estrogens in complex biological samples still remains great challenge. Here we reported the fabrication of a novel core-shell structured magnetic cyclodextrin microporous organic network (Fe3O4@CD-MON) for rapid magnetic solid phase extraction (MSPE) of four estrogens in human serum and urine samples prior to HPLC-UV determination. The uniform spherical core-shell Fe3O4@CD-MONs was successfully regulated by altering the reactive monomers and solvents. The Fe3O4@CD-MONs owned high specific surface area, good hydrophobicity, large superparamagnetism, and abundant extraction sites for estrogens. Under optimal conditions, the proposed MSPE-HPLC-UV method provided wide linearity range (2.0–400 μg L−1), low limits of detection (0.5–1.0 μg L−1), large enrichment factors (183–198), less adsorbent consumption (3 mg), short extraction time (3 min), and good stability and reusability (at least 8 cycles). The established method had also been successfully applied to the enrichment and detection of four estrogens in serum and urine samples with a recovery of 88.4–105.1 % and a relative standard deviation of 1.0–5.9 %. This work confirmed the feasibility of solvent and monomer regulation synthesis of Fe3O4@CD-MON composites, and revealed the great prospects of magnetic CD-MONs for efficient enrichment of trace estrogens in complex biological samples.

Magnetic β-Cyclodextrin Polymer Nanoparticles for Efficient Adsorption of U(VI) from Wastewater

It is a central issue to eliminate radioactive uranium (U(VI)) efficiently from water. In this manuscript, β-cyclodextrin was cross-linked with 2,3,5,6-tetrafluoro-1,4-benzenedicarbonitrile, and then a carboxylation reaction was used to prepare porous cross-linked polymers rich in carboxyl groups (CA-PCDPs). Subsequently, magnetic nanoparticles (MNPs) were loaded onto the CA-PCDPs via coprecipitation, and magnetic porous β-cyclodextrin polymer nanoparticles (CA-PCDP@MNPs) were successfully obtained, which were used for efficient elimination of U(VI) from nuclear wastewater solution. Moreover, SEM, FTIR, VSM, BET, and XRD were employed to investigate the CA-PCDP@MNP and found that it had a well-developed porous structure, high specific surface area, and abundant oxygen-containing functional groups (carboxyl, hydroxyl, C-O-C, Fe-O, etc.), providing sufficient active sites for chelating uranyl ions. Experiments illustrated that the CA-PCDP@MNP had efficient removal ability for U(VI), and the maximum theoretical adsorption amount for U(VI) reached 245.66 mg/g at pH 6.0 and 303 K. Moreover, the adsorption process was more suitable for the quasi second-order kinetic model and Langmuir adsorption isotherm model, indicating that the adsorption process was chemical adsorption. Meanwhile, the CA-PCDP@MNPs also exhibited fast response magnetic recovery ability and excellent regeneration and recycling ability. In addition, the data of the adsorption mechanism demonstrated that oxygen-containing functional groups, which were rich on the surface of CA-PCDP@MNPs, were the main binding active sites of U(VI). From the above results, it can be deduced that the CA-PCDP@MNP has a good application prospect in the practical application of nuclear wastewater treatment.

Simultaneous reduction and sequestration of hexavalent chromium by magnetic β-Cyclodextrin stabilized Fe3S4

In this study, β-Cyclodextrin (CD) modified Fe3S4 nanomaterials were synthesized by a one-step facile strategy and investigated for the removal of Cr(VI). The resulted CD-Fe3S4 exhibited enhanced removal efficiency toward Cr(VI) than bared Fe3S4 with a maximum capacity of 220.26 mg·g-1 as the molar ratio of CD-to-Fe3S4 at 0.2. The effective performance of CD-Fe3S4 toward Cr(VI) could well maintain under oxic conditions and a wide pH range of aqueous solution. A high selectivity for Cr(VI) was achieved in the presence of coexisting cations and anions. More significantly, a single treatment step of CD-Fe3S4 effectively removed chromium from actual electroplating wastewater to the detection limit of 0.004 mg·L-1 that far below the WHO limitation of Cr (VI) (<0.05 mg·L-1) combing with the rapid magnetic separation without adjusting the pH value of wastewater at 7. The effective removal of Cr (VI) by CD-Fe3S4 involved a complex process of surface adsorption/reduction, and solution homogenous reduction and subsequent sequestration of Cr(III) achieving the effective removal of aqueous total Cr. The superior Cr (VI) removal capability and facial separation of CD-Fe3S4 attained its prominent potential application as an effective material for the Cr(VI) removal.

Synthesis of folic acid-conjugated glycodendrimer with magnetic β-cyclodextrin core as a pH-responsive system for tumor-targeted co-delivery of doxorubicin and curcumin

One of the most important applications of nanotechnology in cancer treatment involves the design of magnetic nanocomposites for the targeted delivery of anticancer drugs to cancer cells. This study aims to develop a novel, appropriate, and efficient magnetic carrier having antioxidant properties for the controlled release of anticancer drugs, hydrophilic doxorubicin (DOX), and hydrophobic curcumin (CUR) to cancer cells using folic acid conjugated with magnetic glycodendrimer (Fe 3 O 4 -β-CD-CTD-FA). The synthesized carrier was characterized using DLS, EDX, XRD, BET, FT‐IR, Zeta potential, VSM, TEM, and SEM analysis. The TEM results showed that synthesized Fe 3 O 4 -β-CD-CTD-FA have a spherical-like core-shell structure with an average diameter of approximately 533 nm. The encapsulation efficiency (EE) of Fe 3 O 4 -β-CD-CTD-FA was found to be 98.96% for DOX and 70.91% for CUR. The release studies of DOX and CUR from Fe 3 O 4 -β-CD-CTD-FA showed that maximum release occurs at pH 5 which means it has a controlled pH-responsive behavior. In vitro cytotoxicity and confocal microscopy of the as-synthesized Fe 3 O 4 -β-CD-CTD-FA in MDA-MB-231 cells clearly showed that the prepared carrier had no significant cytotoxicity and could easily enter the cell. Furthermore, the in vitro antioxidant capacity of Fe 3 O 4 -β-CD-CTD-FA was evaluated by DPPH assay and the results exhibited that the synthesized carrier has excellent antioxidant activity (75.45%). Therefore, the obtained glycodendrimer in this study due to their target ability under a magnetic field, excellent biocompatibility, good colloidal stability, simple preparing method, and good antioxidant activity could be used as a promising targeted co-drug delivery system for cancer therapy. • Fe 3 O 4 -β-CD-CTD-FA nanocomposite with antioxidant properties successfully prepared. • The resulted nanocomposite was applied for co-delivery of DOX and CUR to breast cancer cells. • In vitro cytotoxicity and confocal microscopy illustrated that the nanocomposite had no significant cytotoxicity and could easily enter the cells.

1-Octyl-3-methylimidazolium hexafluorophosphate-functionalised magnetic poly β-cyclodextrin for magnetic solid-phase extraction ofpyrethroids from tea infusions

ABSTRACT In this study, a novel sorbent, 1-octyl-3-methylimidazolium hexafluorophosphate functionalised magnetic poly β-cyclodextrin, was successfully synthesised and applied to magnetic solid-phase extraction for the determination of pyrethroids in tea infusions. The sorbent was characterised by transmission electron microscopy, energy-dispersive spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, vibrating sample magnetometer and Brunauer–Emmett–Teller measurement. All factors affecting extraction efficiency, such as sorbent amount, extraction time, ionic strength and desorption conditions, were optimised individually. Under the chosen conditions, wide linearity (2.5–500 μg L−1) with determination coefficients ranging from 0.9995 to 0.9999, low limits of detection of 0.32–0.54 μg L−1 and good precision (intra-day: 2.6–7.0%; inter-day: 3.5–7.6%) were achieved for four pyrethroids in tea infusions. The relative recoveries of target analytes in real tea infusion samples were from 70% to 101% with relative standard deviations lower than 9.1%. We conclude that the proposed method is promising in the detection of pyrethroids in tea infusions.

Specific recognition of protein by deep eutectic solvent-based magnetic β-cyclodextrin molecularly imprinted polymer.

Amagnetic β-cyclodextrin (MCD) surface molecularly imprinted polymer (MIP) based on deep eutectic solvents (DESs) as cross-linker and functional monomer (MCD@DES-MIP) was successfully synthesized for the specific recognition of bovine hemoglobin (BHb). The adsorption behavior of MCD@DES-MIP for BHb was investigated by adsorption thermodynamics, adsorption kinetics, and pH control experiments. The maximum adsorption capacity of MCD@DES-MIP for BHb under the optimized conditions was 195.94mgg-1 and the imprinting factor was 4.68. In addition, the competitive adsorption experiments demonstrated that MCD@DES-MIP showed excellent selective extraction ability for BHb in the binary mixture of BHb and bovine serum albumin (BSA). The actual sample analysis manifested that MCD@DES-MIP effectively separated BHb from complex samples. The results of circular dichroism spectra proved that the secondary structure of BHb did not change during elution. The result indicated that MCD@DES-MIP can be used as a new imprinting material for the separation and purification of BHb.Graphical abstract Magnetic imprinted microspheres (MCD@DES-MIP) were prepared by free radical polymerization using magnetic β-cyclodextrin (MCD) as carrier, deep eutectic solvents (DESs) as functional monomer and cross-linker. MCD@DES-MIP show high adsorption capacity and excellent selectivity for BHb.

Boronate affinity-modified magnetic β-cyclodextrin polymer for selective separation and adsorption of shikimic acid

Polymer of cyclodextrin (CD) is still of great sustainable interest in the scientific research attributing to its excellent physicochemical properties. Owing to its water solubility and superior binding capacity, CD is usually modified through various strategies to exploit its application area. Herein, for the first time, magnetic β-cyclodextrin (β-CD) polymer is endowed with boronate affinity property via mild chemical modifications to specifically separate natural drug raw material shikimic acid (SA). The uniform morphology, magnetic response ability and composition analysis of the porous adsorbent were highly supported by the characterizations. The capture process towards SA depending on the pH value is explored in detail by adsorption kinetics, equilibrium, selectivity and reusability. It is found that specific recognition sites decorated on the surface of magnetic β-CD provides strength support for selective adsorption and separation of shikimic acid. The prepared adsorbent shows high adsorption quantity (Q, mg g−1) of 31.60 mg g−1 at 25 °C, high specific recognition and good adsorption capacity (above 83.7%) and stability after five cycles. This study gives a new sight on the utilization of porous β-CD-based material by grafting functional boric acid group for specific capture of natural cis-diol-containing compounds.

Fabrication of a novel bio-sorbent based on magnetic β-cyclodextrin composites modified by polymeric deep eutectic solvent for the efficient separation of Ovalbumin

In this work, a novel magnetically responsive sorbent is fabricated by immobilizing the β-cyclodextrin-grafted magnetic Fe3O4 nanoparticles with polymeric deep eutectic solvents (M-β-CD@PDES). The successful preparation of the sorbent is confirmed by X-ray diffraction (XRD), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), Fourier transform infrared spectrometry (FT-IR) and transmission electron microscopy (TEM). Simultaneously, the adsorption performance of the M-β-CD@PDES for Ovalbumin (OVA) is investigated by batch adsorption experiments. The results reveal that the coupling of polymeric deep eutectic solvents with the M-β-CD microspheres could greatly enhances the adsorption capacity for OVA. Besides, the adsorption parameters in terms of solution pH value, the concentration of OVA solution, adsorption time and temperature are explored and optimized. It turns out that the maximum adsorption capacity can reach up to 151.62 mg/g. Meanwhile, the analysis of solution pH couple with the Zeta potentials of M-β-CD@PDES demonstrates that the electrostatic interaction plays a significant role in the adsorption procedure. The regeneration of M-β-CD@PDES is also explored and the result indicates the sorbent has certain durability after three adsorption–desorption cycles. Furthermore, on the basis of the analysis of SDS-PAGE, the sorbent can be applied to the adsorption of OVA from real egg white. All the above highlight the developed M-β-CD@PDES composites is supposed to have great potentials in the separation of biomolecules.

Preparation of magnetic β-cyclodextrin ionic liquid composite material with different ionic liquid functional group substitution contents and evaluation of adsorption performance for anionic dyes

In this study, we successfully prepared two magnetic graphene oxide composites, specifically (mGO@ILs(1)-βCD and mGO@ILs(2)-βCD), with different ionic liquid functional group substitution contents on the β-cyclodextrin (β-CD). Structural characterization of the composite material was performed using Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, specific surface area and pore volume measurements. Comparison of the adsorption performance of the two materials for anionic dyes (lemon yellow (LY), sunset yellow (SY), and ponceau 4R (P4R)) in simulated wastewater. Effect of initial pH value, contact time were studied and discussed in terms of affinity and adsorption efficiency. The adsorption of the anionic azo dye by two adsorbent followed Langmuir adsorption isotherm models and pseudo-second-order kinetics. Noticeably, the maximum adsorption capacity based on the Langmuir model showed that mGO@ILs(2)-βCD was better than mGO@ILs(1)-βCD. Additionally, the adsorbent maintains excellent adsorption capacity after five cycles of adsorption-desorption and has remarkable selective separability. The results showed that the high-density substitution content of the ionic liquid functional groups on β-cyclodextrin in mGO@ILs(2)-βCD is helpful to improve the adsorption capacity and efficiency.

Magnetic Fe3O4@SiO2@β-cyclodextrin for solid phase extraction of methyl parathion and fenthion in lettuce samples.

In this study, magnetic Fe3O4@SiO2@β-cyclodextrin copolymerized microparticles were synthesized and applied for the extraction of methyl parathion and fenthion in lettuce samples followed by HPLC-UV detection. The magnetic β-cyclodextrin copolymerized microparticles were prepared by dispersion polymerization with acryloyl β-cyclodextrin as the functional monomer and ethylene glycol dimethyacrylate as the crosslinker. The composite magnetic microparticles were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, magnetic measurement, and thermogravimetric analysis, and used as the adsorbent of magnetic solid-phase extraction (MSPE) for methyl parathion and fenthion. The extraction conditions including sample pH and ionic strength, desorption solvent type and volume, and adsorption and desorption times were optimized. Under the optimal extraction conditions, an MSPE-HPLC-UV method was developed for the detection of methyl parathion and fenthion in lettuce. Wide linear ranges of 1.0-200 μg kg-1 (R2 = 0.9998) for methyl parathion and 1.5-200 μg kg-1 (R2 = 0.9978) for fenthion were obtained and the limits of detection were 0.3 μg kg-1 for methyl parathion and 0.5 μg kg-1 for fenthion in lettuce, respectively. The proposed method was applied for the determination of methyl parathion and fenthion in lettuce with satisfactory recoveries between 89.2-101.2%, and relative standard deviations were less than 9.1%. Thus, the MSPE-HPLC-UV method has high accuracy and sensitivity for the analysis of methyl parathion and fenthion in lettuce samples.

A deep eutectic solvent modified magnetic β-cyclodextrin particle for solid-phase extraction of trypsin

An environmentally friendly deep eutectic solvent (DES) composed of trifluoroacetamide and benzyltrimethylammonium chloride modified β-cyclodextrin (CD) grafted magnetic beads (MB-NH2@CD@DES) were synthesized for the first time and applied to the solid-phase extraction of trypsin. Among the five trypsin extractants prepared in this work (MB, MB-NH2, MB-NH2@CD, MB-NH2@DES, MB-NH2@CD@DES), the extractant MB-NH2@CD@DES with higher extraction capacity for trypsin was selected as final extractant. The extraction capacity of MB-NH2@CD@DES for trypsin can reach up to 549.87 mg⋅g−1 under the optimized conditions. The Langmuir adsorption equilibrium was found fitted better with equilibrium relation between MB-NH2@CD@DES and trypsin than Freundlich adsorption equilibrium. And a superior extraction for trypsin was verified by comparing the extraction capacity of MB-NH2@CD@DES for trypsin and four other common proteins. Compared with some reported trypsin extractants, the MB-NH2@CD@DES had a shorter extraction process, higher extraction capacity, more convenient operation of separation, a safer and more environmentally friendly synthesis process. With the optimized eluent, a great elution rate (74.32%) of trypsin was achieved. The absolute recovery of trypsin in trypsin standard solution was calculated to be 16.8%. And the extraction capacity of MB-NH2@CD@DES toward trypsin still maintained well after ten times recycling and reuse. The detection limit (LOD) and quantitative limit (LOQ) were 0.072 mg⋅mL−1 and 0.240 mg⋅mL−1 respectively. By sodium dodecyl sulfate polyacrylamide gel electrophoresis experiment, the extraction ability of MB-NH2@CD@DES to trypsin from real sample was fully demonstrated. All above results showed the potential of fabricated MB-NH2@CD@DES as a superior extractant for trypsin from real complex samples.

A new magnetic β-cyclodextrin polyurethane nanocomposite for the removal of organic pollutants in wastewater

Herein, we report the synthesis of a new thermally stable magnetic polyurethane nanocomposite (MPUNc) (14) containing azobenzene moiety and β-cyclodextrin (β-CD) and its application in removing some organic pollutants from water. First, 4,4′-azodibenzene dicarboxylic acid (2) was synthesized and then it was converted to 4,4′-azodibenzene diacyl azide (3). MPUNc (14) was synthesized by grafting magnetic nanoparticles (MNPs) (11) onto β-CD-AzoPU (10). The properties of the MPUNc (14) were characterized by FTIR, 1H NMR, XRD, SEM, EDX, VSM, and TGA. By adding MPUNc (14) to PVA, the stress–strain curves of the resulting blend showed a ductile fracture due to the digressing toughness of PVA. The magnetic saturation (Ms) values demonstrated that the magnetic property of Fe3O4 was reduced when coated by SiO2. The TGA thermogram of MPUNc (14) showed a 10% weight loss below 300 °C. In addition, the weight loss of about 33% between 350 and 750 °C was due to the chemical decomposition of β-CD-AzoPU (10) and EPO moieties. Thus, the results showed that the grafted β-CD-AzoPUs (10) to MNPs (11) had a density of about 18%. The MPUNc (14) was used as a new absorbent to remove 4-chlorophenol (4-CP) and 4-nitrophenol (4-NP) from water. Besides, the effects of pH, time, temperature, and the absorbent dosage on the adsorption ability were studied. The results showed that the pH and the adsorbent dosage had a key role in removing 94% of the 4-NP and 91.3% of 4-CP at the optimized pH of 3 using 50 mg of the sorbent.

Magnetic β-Cyclodextrin Nanosponges for Potential Application in the Removal of the Neonicotinoid Dinotefuran from Wastewater.

This article describes the use of β-cyclodextrin-based carbonate nanosponges (NSs) decorated with superparamagnetic Fe3O4 nanoparticles to study and investigate the potential removal of dinotefuran (DTF) from wastewater. The NS-DTF inclusion compound was characterized by transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), UV-visible spectroscopy (UV-VIS), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD) and proton nuclear magnetic resonance (1H-NMR). The adsorption efficiency of NSs was evaluated as function of different contact times. The results confirmed that the NSs have a favourable sorption capacity for the chosen guest, as the polymers exhibited a maximum adsorption of 4.53 × 10−3 mmol/g for DTF. We also found that magnetic NSs show good reusability as they maintain their efficiency after eight adsorption and desorption cycles. Our studies and characterization by means of SEM, TEM, EDS, vibrating sample magnetometer (VSM) and UV-VIS also show that NSs with magnetic properties are excellent tools for insecticide removal from aqueous environments.

Selective and fast recovery of rare earth elements from industrial wastewater by porous β-cyclodextrin and magnetic β-cyclodextrin polymers

Recovery of rare earth elements (REEs) from industrial wastewater has drawn great attention due to their potential environmental toxicity, as well as their high demand in modern technologies. In this study, we developed a magnetic composite based on the high surface area porous β-cyclodextrin polymer (P-CDP), namely P-CDP@Fe3O4. Both P-CDP and P-CDP@Fe3O4 rapidly sequester REEs such as Nd, Gd, Eu, and Y, reaching equilibrium in less than 10 min and fitting the Langmuir isotherm model with maximum adsorption capacities ranging from 7.76 to 9.59 mg/g at 25 °C when the highest initial concentration was 100 mg/L. Besides, the recovery of these REEs was not affected by competitive alkali, alkaline earth, and transition metal ions in model studies and industrial wastewater as revealed by the recovery efficiencies, which ranged from 62% to 100% indicating an excellent selectivity on both adsorbents. In addition, both adsorbents can be fully regenerated under mildly acidic conditions for at least five consecutive cycles. Moreover, P-CDP@Fe3O4 can be easily isolated by an external magnetic field which simplifies its synthesis and usability. It also overcomes the clogging and high backpressure issues of P-CDP, which facilitates its application for REEs recovery as compared with P-CDP. These characteristics demonstrate the promise of P-CDP and P-CDP@Fe3O4 for the pollution control and recovery of REEs.

A study of adsorption of Cu2+ on magnetic β-cyclodextrin pyrolysis products

Magnetic β-cyclodextrin pyrolysis products at 500°C were prepared from β-cyclodextrin pyrolysis products as raw materials, and the adsorption performance of magnetic β-cyclodextrin pyrolysis products on Cu2+ was studied by nitrogen nitriding. this study provided a theoretical basis for the preparation of highly effective adsorbents and the prediction of their adsorption performance on Cu2+. The results show that the adsorption behavior of Cu2+ by magnetic β-cyclodextrin pyrolysis products conforms to the pseudo-second-order kinetic equation. The isothermal adsorption curve conforms to the Langmuir equation, and the maximum adsorption capacity is 405.99mg·g−1.

Green synthesis of a magnetic β-cyclodextrin polymer for rapid removal of organic micro-pollutants and heavy metals from dyeing wastewater

Adsorption is one of the most preferred techniques in the advanced treatment of dyeing wastewater. Magnetic porous materials with good adsorption performance, excellent reusability, and a green synthesis route are highly desirable adsorbents in commerce. In this study, we synthesized a magnetic β-cyclodextrin polymer (MNP-CM-CDP) containing many macro- and ultramicropores in aqueous phase. CO2 adsorption-desorption isotherms and a dye adsorption method provided Langmuir specific surface areas for the MNP-CM-CDP of 114.4 m2 g−1 and 153 m2 g−1, respectively. Model pollutants (BPA, MB, BO2, RhB, Cr(III), Pb(II), Zn(II), and Cu(II)) were rapidly and efficiently removed from the aqueous solution by the MNP-CM-CDP. In addition, the polymer could be easily separated from the solution under an external magnetic field. The adsorption of the contaminants was dependent on pH, while the effects of ionic strength and humic acid were slight in the concentration range studied. The polymer could be easily regenerated at room temperature and retained good adsorption performance. Moreover, the MNP-CM-CDP showed good feasibility for the removal of pollutants from actual dyeing wastewater samples.

Smart cellulose-derived magnetic hydrogel with rapid swelling and deswelling properties for remotely controlled drug release

Although cellulose hydrogels are one of promising biomaterials for drug release carrier, their passive manner of drug release and the absence of remote stimuli response limit their further applications. Herein, we report a simple one-pot method for the synthesis of magnetic β-cyclodextrin (β-CD)/cellulose hydrogel beads, which exhibited rapid swelling–deswelling properties under an external magnetic field (EMF) to remotely control drug release from passive release to stepwise release. The grafted β-CD endows the hydrogel with high drug loading capacity and, simultaneously, the incorporation of Fe3O4 nanoparticles provide the force for stepwise drug release through EMF induced rapid and reversible deformation of 3D network. We demonstrate that the efficiency of the hydrogel in the stepwise drug release dose and rate can be controlled by switching on–off the EMF and adjusting the content of Fe3O4 nanoparticles. Additionally, results from cytotoxicity tests confirmed the excellent biocompatibility of the developed hydrogel, which is promising to be used in the biomedical field.

Magnetite nanoparticles modified β-cyclodextrin PolymerCoupled with KMnO4 oxidation for adsorption and degradation of acetaminophen

Here, a porous superparamagnetic composite material magnetic β-cyclodextrin polymer (MNPs/β-CDP) was prepared and characterized as a adsorbent that may be used for the degradaion of acetaminophen (APAP) in aqueous solution by coupling with potassium permanganate (KMnO4) oxidation. The results of adsorption properties investigation showed that the adsorption rate and capacity of MNPs/β-CDP were better than the component materials. When coupled with KMnO4 oxidation, the degradation efficiency were evaluated with regards to the pseudo-first-order kinetics of 4-CP degradation. As an oxidation reactor, the material effectively alleviated the secondary pollution and water coloration caused by oxidation of KMnO4. Moreover, the materials were directly regenerated by the reaction of KMnO4 with APAP adsorbed in its cavities without additional elution treatment, making it more convenient and environmentally friendly. The repeated degradation experiments demonstrated that MNPs/β-CDP had mechanic stability and reusability. The findings provide novel ideas for the degradation of persistent contaminants in water environments.

Novel porous magnetic nanospheres functionalized by β-cyclodextrin polymer and its application in organic pollutants from aqueous solution

Magnetic β-cyclodextrin (β-CD) porous polymer nanospheres (P-MCD) was fabricated by one-pot solvent thermal method using β-CD immobilized Fe3O4 magnetic nanoparticles with tetrafluoroterephthalonitrile as the monomer. Compared with the β-CD polymerization method reported in the literature,_ENREF_1 the synthetic route is effective and simple, thereby overcoming the harsh conditions that require nitrogen protection and always maintain anhydrous and oxygen-free. Moreover, the immobilization of β-CD on magnetic nanoparticles is combined with the cross-linking polymerization of the cross-linker, leading to a good synergistic effect on the removal of contaminants. Meanwhile, the dispersibility of the magnetic carrier enhances the dispersion of the β-CD porous polymer in the aqueous phase, and improves the inclusion adsorption performance and the adsorption process. P-MCD exhibited superior adsorption capacity and fast kinetics to MB. The maximum adsorption capacity of MB for P-MCD was 305.8 mg g −1, which is more than β-CD modified Fe3O4 magnetic nanoparticles (Fe3O4@β-CD). Moreover, the material had a short equilibrium time (5 min) for MB, high recovery and good recyclability (the adsorption efficiency was still above 86% after five repeated uses).

Highly efficient heterogeneous Fenton activities of magnetic β-cyclodextrin (Fe) framework for Eriochrome black T degradation

Advanced Oxidation Processes (AOP) are the emerging techniques for removing organic pollutants from industrial water streams. However, to establish such a method for industrial applications successfully the knowledgebase of complete mechanism is still incomplete. Herein, β-cyclodextrin coated magnetic Fe3O4 nanocompositewas prepared to enhance the stability and surface activity of Fe3O4. β-cyclodextrin provides more number of surface active groups on the nanoparticles to increase the catalytic activity and stabilizing the particles by preventing aggregation. The material was tested for the degradation of Eriochrome black T (EBT) by the reactive hydroxyl radicals, produced from the decomposition of H2O2 in an AOP. The catalyst has the particle size in the range of 10 ± 2 nm and saturation magnetization value of 45 emu/g, effective for easy separation. The studies focus to evaluate the degradation efficiency of the catalyst by considering various parameters viz. pH, H2O2 dose and catalyst amount at room temperature in a heterogeneous Fenton reaction. LCMS studies show the formation of small degraded products like Prop-1-en-1-ol, Glyoxylic acid etc. after reaction. Our observation implies that β-cyclodextrin coated magnetic nanocomposite has much higher catalytic activity than pure Fe3O4 for degradation of EBT in aqueous medium.