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1.
J Colloid Interface Sci ; 607(Pt 1): 253-268, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34500424

RESUMO

Phenolic compounds are important industrial raw materials for various industrial applications, but phenol-containing wastewater creates significant environmental and biological hazards. To address these issues, a three-dimensional network graphene oxide-cyanoethyltriethoxysilane-ß-cyclodextrin/poly (N-isopropylacrylamide) (GO-CTES-ß-CD/PNIPAM) nanocomposite hydrogel as a phenol recovery adsorbent is prepared herein by in-situ polymerization. Double graft modification on the graphene oxide (GO) via the silane coupling agent 2-cyanoethyltriethoxysilane (CTES) and single (6-tetraethylenepentamine-6-deoxy)-ß-cyclodextrin (NH-ß-CD) compensated the loss of the active sites on both GO and N-isopropylacrylamide (NIPAM), and the hydrogel shows excellent mechanical properties as the chemical crosslinking and physical entanglement of the two components. Consequently, the composite hydrogel achieved an adsorption capacity of 131.64 mg·g-1 for the common environmental toxin 4-NP. After five repeated adsorption-desorption cycles, the hydrogel retained 74% of the initial 4-NP removal ratio. The adsorption results followed pseudo-first-order kinetics, corresponding to heterogeneous multilayer adsorption, which was regulated by a combination of surface adsorption and intra-particle diffusion mechanisms. In general, the nanocomposite hydrogel shows promising application in the field of recycling phenols from wastewater. Also, high photothermal conversion and temperature-sensitive properties are also demonstrated, which makes the hydrogel possessing great potential to be applied in smart microvalves.


Assuntos
Ciclodextrinas , Poluentes Químicos da Água , Acrilamidas , Adsorção , Grafite , Microfluídica , Nanogéis , Fenol , Fenóis , Poluentes Químicos da Água/análise
2.
Food Chem ; 370: 131026, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34509938

RESUMO

Cyclodextrins are garnering increasing attention because they offer several benefits. For instance, cyclodextrins can form several complexes and supramolecular structures not only for food packaging but also for applications in other fields of science. In this review, we discussed the physical and chemical properties of cyclodextrins and the mechanism of their inclusion complex formation. The use of cyclodextrins in various types of food packaging is elaborated upon. We also explain the effects of cyclodextrins on the packaging of fruits, vegetables, meat, fish, and processed foods. Furthermore, some feasible suggestions for future applications are provided. In addition to the positive attributes of cyclodextrins, there are some limitations and drawbacks, which are discussed briefly in this review. In summary, this review can serve as a guide for researchers exploring cyclodextrins for the development of various packaging films.


Assuntos
Ciclodextrinas , Animais , Embalagem de Alimentos
3.
Food Chem ; 366: 130612, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311236

RESUMO

The determination of the kinetics of inclusion processes is significant for the application of inclusion complexes as carriers for bioactive molecules. We determined the kinetic parameters of inclusion between modified ß-cyclodextrin (ß-CD-NH2) and the polyphenols resveratrol (RES) and its structural analog (RESAn1), using the real-time analysis of surface plasmon resonance. The association and dissociation rate constants (ka and kd) showed that RESAn1 inclusion and its dissociation from ß-CD-NH2 were faster than a similar process for RES ( [Formula: see text]  = 3.10∙104 ± 0.14 M-1s-1, [Formula: see text] =1.87∙103 ± 0.11 M-1s-1; [Formula: see text] =0.39 ± 0.02 s-1, [Formula: see text] =0.30 ± 0.02 s-1, at 25 °C). The activated complex formation was also affected by the structural differences between the polyphenols, as showed by the activation energies of the association step ( [Formula: see text] 14.81 ± 0.64 kJ∙mol-1, [Formula: see text] -15.01 ± 0.75 to 82.35 ± 4.47 kJ∙mol-1). These effects of polyphenol structural differences are due to the desolvation process of interacting molecules. These results elucidate the role of small group to the dynamics of the molecular inclusion of ß-CD.


Assuntos
Ciclodextrinas , Cinética , Polifenóis , Resveratrol , Ressonância de Plasmônio de Superfície
4.
Food Chem ; 366: 130616, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34311240

RESUMO

The lipase from Bacillus licheniformis NCU CS-5 was immobilized onto ß-cyclodextrin (CD) grafted and aminopropyl-functionalized chitosan-coated Fe3O4 magnetic nanocomposites (Fe3O4-CTS-APTES-GA-ß-CD). Fourier transform infrared spectroscopy, thermogravimetry analysis, X-ray diffraction, scanning electron microscopy and transmission electron microscopy showed that not only the functionalized magnetic nanoparticles were synthesized but also the immobilized lipase was successfully produced. The immobilized lipase exhibited higher optimal pH value (10.5) and temperature (60℃) than the free lipase. The pH and thermal stabilities of the immobilized lipase were improved significantly compared to the free lipase. The immobilized lipase remained more than 80% of the relative activity at temperature of 60 ℃ and pH 12.0. The immobilized lipase also remained over 80% of its relative activity after 28 days of storage and 15 cycles of application. The application of the immobilized lipase in esterification of isoamyl acetate and pentyl valerate showed that maximum esterification efficiency was achieved in n-hexane having 68.0% and 89.2% respectively. Therefore, these results indicated that the Fe3O4-CTS-APTES-GA-ß-CD nanoparticles are novel carriers for immobilizing enzyme, and the immobilized lipase can be used as an innovative green approach to the synthesis of fruity flavor esters in food industry.


Assuntos
Quitosana , Ciclodextrinas , Nanopartículas de Magnetita , Nanocompostos , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Esterificação , Ésteres , Concentração de Íons de Hidrogênio , Lipase/metabolismo , Fenômenos Magnéticos
5.
Food Chem ; 367: 130664, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343804

RESUMO

Cyclodextrin-based dispersive liquid-liquid microextraction (CD-DLLME) was developed for the determination of triazole and strobilurin fungicides in water, juice, and vinegar samples using high-performance liquid chromatography-diode-array detection (HPLC-DAD). Undecanol, which is a green solvent, was selected as the extraction solvent. A cyclodextrin aqueous solution was chosen as the dispersion solvent and demulsifier to avoid the use of a toxic dispersion solvent and eliminate the centrifugation step. Dispersion and phase separation were completed within 1 and 60 s, respectively. The linear range of this method was 1 to 100 µg L-1. The limits of detection were 0.3 µg L-1 along with the preconcentration factor of 133 and enrichment factor of 124. The recovery was 83.2% to 103.2%. This pretreatment method was fast, simple, and environmentally friendly and was successfully applied to the analysis of triazole and strobilurin fungicide residues in water, juice, and vinegar samples.


Assuntos
Ciclodextrinas , Fungicidas Industriais , Microextração em Fase Líquida , Poluentes Químicos da Água , Ácido Acético , Cromatografia Líquida de Alta Pressão , Fungicidas Industriais/análise , Solventes , Água , Poluentes Químicos da Água/análise
6.
Anal Chem ; 93(45): 15096-15104, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34726389

RESUMO

The separation of chiral enantiomers has gained increasing importance in many research fields, becoming a major research hotspot. 1,1'-Bi (2-naphthol) (BINOL) and 1,1'-binaphthyl-2,2'-diyl hydrogen phosphate (BNP) are referred to as atropisomer chiral molecules, which are essential chiral catalysts and intermediates in several reactions. In this work, BINOL and BNP atropisomers are separated and identified using trapped ion mobility spectrometry (TIMS) to monitor the different mobilities of their derivative complexes. The latter are obtained by the simple mixing of BINOL/BNP, cyclodextrin (CD), and the metal ions through noncovalent interactions. The results indicate that the enantiomer complexes of BINOL/BNP can be separated with a certain specificity, showing that R-, S-BINOL can be separated by the ternary complexes of [BINOL+γ-CD + Rb]+, [BINOL+γ-CD + Cu-H]+, and [BINOL+ß-CD + Cu-H]+ based on the difference in their mobility; similarly, the R-, S-BNP enantiomer can be isolated by the formed ternary complexes of [BNP+α-CD + Ba-H]+, [BNP+ß-CD + Co-H]+, [BNP+ß-CD + Ca-H]+, [BNP+ß-CD + Cu-H]+, [BNP+ß-CD + Fe-H]+, [BNP+ß-CD + Li]+, and [BNP+ß-CD + Sr-H]+. Furthermore, the peak separation rate (Rp-p) of the complexes was calculated, with the Rp-p of the three enantiomers of BINOL being 1.130 and the Rp-p of the seven complexes of BNP reaching 2.089. At last, the different survival yields for the collision energies were found for the enantiomer complexes, revealing the rigid structural differences in the stereospecificity of the enantiomer complexes that result in the separation by the TIMS. Additionally, due to the advantages of simple operation, fast speed, and high sensitivity and because chemical derivatization and chromatographic separation are not required, the developed method can provide a promising and powerful strategy for the separation and identification of binaphthyl derivatives or even other enantiomers of the reaction intermediates.


Assuntos
Ciclodextrinas , Espectrometria de Mobilidade Iônica , Íons , Naftóis , Fosfatos , Estereoisomerismo
7.
AAPS PharmSciTech ; 23(1): 2, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34796406

RESUMO

Daidzein, an aglycone-type isoflavone, is useful in the prevention of atherosclerotic cardiovascular diseases. However, the solubility of daidzein remains relatively low even with pharmaceutical interventions (e.g., γ-cyclodextrin inclusion complex). In the present study, daidzein-cyclodextrin-metal organic framework solid dispersion complexes were prepared by the solvent evaporation method. The physicochemical properties of the complex and its effect on the solubility of daidzein were evaluated. The enhancement effect of a cyclodextrin-metal organic framework on the antioxidant properties of daidzein was verified using a diphenyl-picrylhydrazyl radical scavenging test. Powder X-ray diffraction results showed that the characteristic diffraction peaks of daidzein and cyclodextrin-metal organic framework disappeared and new peaks (2θ = 7.1°, 16.5°) were observed. FT-IR measurements showed that the peak derived from the carbonyl group of daidzein shifted to the lower wavenumber. NOESY 1H-1H NMR showed cross peaks at the proton on the resorcinol side of daidzein and the proton (H-5, H-6) in a cyclodextrin-metal organic framework. Dissolution rate of daidzein at 5 min in distilled water was 0.06% for daidzein alone while the daidzein inclusion complex was about 100%. When fasted state simulated intestinal fluid was used, the dissolution rate of the daidzein complex was about 71% compared with that of daidzein alone (~ 3.0%) at 5 min. The daidzein inclusion complex improved the antioxidant capacity to ~ 1.3 times (17.8 µg/mL) compared to the IC50 of daidzein alone (22.9 µg/mL). Preparations of cyclodextrin-metal organic framework inclusion complexes will be a platform in developing pharmaceutical formulations to enhance the bioavailability and activity of drugs.


Assuntos
Ciclodextrinas , Isoflavonas , Estruturas Metalorgânicas , beta-Ciclodextrinas , Antioxidantes , Varredura Diferencial de Calorimetria , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
8.
J Chromatogr A ; 1658: 462588, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34662824

RESUMO

A headspace single drop microextraction (HS-SDME) method coupled with high performance liquid chromatography was developed to compare the extraction of eighteen aromatic organic pollutants from aqueous solutions using cyclodextrin-based supramolecular deep eutectic solvents (SUPRADESs) and alkylammonium halide-based conventional deep eutectic solvents (DESs). Different derivatives of beta-cyclodextrin (ß-CD) were employed as hydrogen bond acceptors (HBA) in SUPRADESs and the extraction performance investigated. SUPRADES comprised of the 20 wt% native ß-CD HBA provided the highest enrichment factors of analytes compared to SUPRADESs comprised of other derivatives of ß-CD (random methylated ß-cyclodextrin, heptakis(2,3,6-tri-O-methyl)-ß-cyclodextrin, and 2-hydroxypropyl ß-cyclodextrin). In addition, native ß-CD and its derivatives were dissolved in the neat DESs and their effect on the extraction of analytes examined. Dissolution of 20 wt% native ß-CD in the choline chloride ([Ch+][Cl-]):2Urea DES resulted in a significant increase in the extraction efficiencies of target analytes compared to the neat [Ch+][Cl-]:2Urea DES. Under optimum conditions, the extraction method required a solvent microdroplet of 6.5 µL, 1000 rpm stir rate, 30% (w/v) salt concentration, and a temperature of 40 °C. The tetrabutylammonium chloride: 2 lactic acid DES resulted in the highest enrichment factors while the [Ch+][Cl-]:2Urea DES had the lowest for most of the analytes among the evaluated solvents. The method provided limits of detection (LODs) down to 35 µg L-1. Furthermore, the developed method was applied for the analysis of spiked tap and lake water, where relative recoveries ranging from 83.7% ̶ 119.7% and relative standard deviations lower than 19.2% were achieved.


Assuntos
Ciclodextrinas , Microextração em Fase Líquida , Limite de Detecção , Solventes , Água
9.
Molecules ; 26(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34641409

RESUMO

The online preconcentration technique, cyclodextrin-assisted sweeping (CD-sweeping), coupled with micellar electrokinetic chromatography (MEKC) was established to determine 13-cis-retinoic acid (13-cis-RA), all-trans-retinoic acid (all-trans-RA) and 4-oxo-13-cis-retinoic acid (4-oxo-13-cis-RA) in human plasma. A CD-sweeping buffer (45 mM borate (pH 9.2), containing 80 mM sodium dodecyl sulfate (SDS) and 22 mM hydroxypropyl ß-CD (HP-ß-CD) was introduced into the capillary and, then, the sample dissolved in 70 mM borate (pH 9.2): methanol = 9:1 (v/v) was injected into capillary by pressure. The separation voltage was 23 kV. Compared to the conventional cyclodextrin-micellar electrokinetic chromatography (CD-MEKC) method, the new technique achieved 224-257-fold sensitivity enrichment of analytes. The limits of detection of 13-cis-RA, all-trans-RA were 1 ng/mL, whereas that of 4-oxo-13-cis-RA was 25 ng/mL in plasma. The linear ranges of 13-cis-RA, all-trans-RA were between 15 and 1000 ng/mL, whereas that of 4-oxo-13-cis-RA was between 75 and 1500 ng/mL. The coefficient of correlation between the concentration of analytes and peak area ratio of analytes and internal standard (2, 4-dihydroxy-benzophenone) for intra-day (n = 3) and inter-day (n = 5) analyses were both greater than 0.999. The optimized experimental conditions were successfully applied to determine 13-cis-retinoic acid and its metabolites in plasma samples from a patient during the administration of 13-cis-RA for treating acne.


Assuntos
Cromatografia Capilar Eletrocinética Micelar/métodos , Ciclodextrinas/química , Isotretinoína/sangue , Isotretinoína/metabolismo , Micelas , Manejo de Espécimes/métodos , Fármacos Dermatológicos/sangue , Fármacos Dermatológicos/metabolismo , Humanos
10.
Anal Chim Acta ; 1184: 339017, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34625257

RESUMO

Penicillamine (Pen) is a common chiral drug that is obtained from penicillin. Between the two enantiomers of Pen, only D-Pen can be used to treat cystinuria and rheumatoid arthritis while L-Pen is toxic. Therefore, it requires great efforts for the research of the rigorous analysis and distinction of the two enantiomers. The non-covalent combination of chiral molecules and chiral selectors (CSs) has been proved as a unique strategy for chiral distinction by ion mobility spectrometry in coupling with -mss spectrometry (IM-MS). Here, we developed a simple method to distinguish D, L-Pen by using special CSs for IM-MS separation. The CSs utilized here include cyclodextrins (CD) and linear chain oligosaccharides plus metal ions. We found that non-covalent complexes [Pen+ß-CD + Li]+ could be easily formed by electrospray ionization of the mixture of the solution, and the chirality of Pen could be effectively recognized by measuring their mobilities due to the different collision cross collision sections of [D-Pen+ß-CD + Li]+ and [L-Pen+ß-CD + Li]+. A detailed analysis of [Pen+ß-CD + Li]+ was then conducted by the optical rotation measurements and NMR experiments to reveal their structural differences. Furthermore, DFT calculation showed the differences of molecular conformation between the complexes. The results provide a new powerful method for fast analysis and recognition of chirality of Pen compounds by IM-MS.


Assuntos
Ciclodextrinas , Espectrometria de Mobilidade Iônica , Íons , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Penicilamina
11.
Int J Pharm ; 609: 121130, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34600052

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the prime pathogens responsible for surgical site infection (SSI). Treatment of SSI remains challenging because of resistant nature of MRSA, which is a major threat in recent years. Our previous work revealed the antibacterial potential of catechin isolated from cashewnut shell against MRSA. However, the application of catechin to treat MRSA-mediated SSI is hampered because of its poor solubility and low trans-dermal delivery. Hence, the present study focused on developing catechin-in-cyclodextrin-in-phospholipid liposome (CCPL) and evaluating its physicochemical characteristics and anti-infective efficacy through in vitro and in vivo models. Encapsulation of catechin with ß-cyclodextrin and soybean lecithin was confirmed through UV-Vis spectroscopy, FTIR, and XRD techniques, while TEM imaging revealed the size of CCPL (206 nm). The CCPL displayed a higher level of water solubility (25.13%) and in vitro permeability (42.14%) compared to pure catechin. A higher level of encapsulation efficiency (98.9%) and antibacterial activity (19.8 mm of ZOI and 31.25 µg/mL of MIC) were noted in CCPL compared to the catechin/cyclodextrin complex. CCPL recorded significant and dose-dependent healing of the incision, significant reduction of bacterial count, improved epithelization, and effective prevention of inflammation in skin samples of SSI-induced Balb/c mice. Data of the present work suggest that the CCPL could be considered as a novel and potential candidate to mitigate MRSA-mediated SSI after clinical trials.


Assuntos
Catequina , Ciclodextrinas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Antibacterianos/uso terapêutico , Lipossomos , Camundongos , Fosfolipídeos , Infecções Estafilocócicas/tratamento farmacológico , Infecção da Ferida Cirúrgica/tratamento farmacológico
12.
J Equine Vet Sci ; 105: 103719, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34607680

RESUMO

The present study aimed to compare semen parameters and fertility of cooled donkey semen extended in a commercially available skim milk (SKM) based extender and the same extender with cholesterol-loaded cyclodextrin (SKM-CLC). In Experiment 1, thirty-five ejaculates from seven jacks were split in SKM and SKM-CLC, extended at 50 million sperm/mL and stored at 5°C for 48 hours. Total motility (TM), progressive motility (PM), percentage of sperm with rapid motility (RAP) were assessed with CASA. Plasma membrane stability (PMS), and high mitochondrial membrane potential (HMP) were assessed with the combination of Yo-Pro and MitoStatusRed with flow cytometry. Semen was assessed before (0), 24 and 48h after cooling. In Experiment 2, two estrous cycles of 15 mares were used for fertility assessment. Mares were examined every other day by transrectal ultrasonography and had ovulation induced with 250 µg of histrelin acetate when a ≥35 mm follicle was first detected. Mares were randomly inseminated with semen obtained from one jack. Semen was extended in either SKM or SKM-CLC and cooled-stored for 24 hours. Pregnancy diagnosis was carried out 15-day post-ovulation. Data were analyzed with a mix model and Tukey's as posthoc and logistic regression model. Significance was set at P ≤ .05. There were no differences in TM, PM, RAP, PMS, and HMP for semen extended in either extender immediately before cooling (P > .05). There was a reduction in TM, PM, RAP, PMS, and HMP overtime across groups (P < .05); however, semen extended with SKM-CLC had superior TM, PM, RAP, PMS, and HMP than semen extended in SKM at 24- and 48-hours post-cooling (P < .05). Mares bred with semen extended in SKM had a lower conception rate (13%, 2/15 cycles) than cycles bred with SKM-CLC (47%, 7/15 cycles; P < .05). In conclusion, incorporating CLC into SKM extender improved cooling ability and fertility of donkey semen in horse mares. It remains to be determined if similar results can be obtained in clinical practice with mares and jennies.


Assuntos
Ciclodextrinas , Preservação do Sêmen , Animais , Colesterol , Equidae , Feminino , Fertilidade , Cavalos , Leite , Gravidez , Sêmen , Preservação do Sêmen/veterinária , Motilidade Espermática
13.
Anal Chem ; 93(42): 14161-14168, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34641671

RESUMO

Blockers of pore-forming toxins (PFTs) limit bacterial virulence by blocking relevant channel proteins. However, screening of desired blockers from a large pool of candidate molecules is not a trivial task. Acknowledging its advantages of low cost, high throughput, and multiplicity, DiffusiOptoPhysiology (DOP), an emerging nanopore technique that visually monitors the states of individual channel proteins without using any electrodes, has shown its potential use in the screening of channel blockers. By taking different α-hemolysin (α-HL) mutants as model PFTs and different cyclodextrins as model blockers, we report direct screening of pore blockers solely by using fluorescence microscopy. Different combinations of pores and blockers were simultaneously evaluated on the same DOP chip and a single-molecule resolution is directly achieved. The entire chip is composed of low-cost and biocompatible materials, which is fully disposable after each use. Though only demonstrated with cyclodextrin derivatives and α-HL mutants, this proof of concept has also suggested its generality to investigate other pore-forming proteins.


Assuntos
Toxinas Bacterianas , Ciclodextrinas , Nanoporos , Eletrodos , Proteínas Hemolisinas
14.
Molecules ; 26(19)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34641590

RESUMO

In the few last years, nanosystems have emerged as a potential therapeutic approach to improve the efficacy and selectivity of many drugs. Cyclodextrins (CyDs) and their nanoparticles have been widely investigated as drug delivery systems. The covalent functionalization of CyD polymer nanoparticles with targeting molecules can improve the therapeutic potential of this family of nanosystems. In this study, we investigated cross-linked γ- and ß-cyclodextrin polymers as carriers for doxorubicin (ox) and oxaliplatin (Oxa). We also functionalized γ-CyD polymer bearing COOH functionalities with arginine-glycine-aspartic or arginine moieties for targeting the integrin receptors of cancer cells. We tested the Dox and Oxa anti-proliferative activity in the presence of the precursor polymer with COOH functionalities and its derivatives in A549 (lung, carcinoma) and HepG2 (liver, carcinoma) cell lines. We found that CyD polymers can significantly improve the antiproliferative activity of Dox in HepG2 cell lines only, whereas the cytotoxic activity of Oxa resulted as enhanced in both cell lines. The peptide or amino acid functionalized CyD polymers, loaded with Dox, did not show any additional effect compared to the precursor polymer. Finally, studies of Dox uptake showed that the higher antiproliferative activity of complexes correlates with the higher accumulation of Dox inside the cells. The results show that CyD polymers could be used as carriers for repositioning classical anticancer drugs such as Dox or Oxa to increase their antitumor activity.


Assuntos
Antineoplásicos/uso terapêutico , Celulose/uso terapêutico , Ciclodextrinas/uso terapêutico , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/uso terapêutico , Oxaliplatina/uso terapêutico , Células A549 , Motivos de Aminoácidos , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Celulose/química , Ciclodextrinas/química , Doxorrubicina/química , Portadores de Fármacos/química , Células Hep G2 , Humanos , Nanopartículas/química , Oxaliplatina/química , beta-Ciclodextrinas/química , beta-Ciclodextrinas/uso terapêutico , gama-Ciclodextrinas/química , gama-Ciclodextrinas/uso terapêutico
15.
Langmuir ; 37(38): 11406-11413, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34528811

RESUMO

In the present study, we investigated the effect of permodified 2,3,6-tri-O-trimethylsilyl ß- and γ-cyclodextrin (TMS·ß-CD, TMS·Î³-CD) encapsulation on the optical, electrochemical, morphological, and supramolecular arrangements of a poly[2,7'-(9,9-dioctylfluorene-alt-2',7-fluorene)] PF copolymer. For this purpose, the photophysical properties and Langmuir monolayer formation of PF·TMS·ß-CD and PF·TMS·Î³-CD polyrotaxanes were investigated and compared with those of the reference PF. Surface pressure-area isotherms and Brewster angle microscopy studies indicated the capability of both polyrotaxanes to organize into larger and homogeneous 2D supramolecular assemblies at the air-water interface. The obtained results suggest that the presence of the surrounding TMS·ß-CD and TMS·Î³-CD macrocycles on the PF backbones leads to changes in the conformation and hydrophobicity of the film surfaces. Our investigation offers a method to assess the impact of TMS-CD encapsulation on the control of 2D monolayer formation, with particular attention on the generation of stable PF monolayers for organic electronic devices.


Assuntos
Ciclodextrinas , Rotaxanos , Microscopia , Propriedades de Superfície , Água
16.
Molecules ; 26(17)2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34500845

RESUMO

Molecular crosstalk between the cellular epigenome and genome converge as a synergistic driver of oncogenic transformations. Besides other pathways, epigenetic regulatory circuits exert their effect towards cancer progression through the induction of DNA repair deficiencies. We explored this mechanism using a camptothecin encapsulated in ß-cyclodextrin-EDTA-Fe3O4 nanoparticles (CPT-CEF)-treated HT29 cells model. We previously demonstrated that CPT-CEF treatment of HT29 cells effectively induces apoptosis and cell cycle arrest, stalling cancer progression. A comparative transcriptome analysis of CPT-CEF-treated versus untreated HT29 cells indicated that genes controlling mismatch repair, base excision repair, and homologues recombination were downregulated in these cancer cells. Our study demonstrated that treatment with CPT-CEF alleviated this repression. We observed that CPT-CEF exerts its effect by possibly affecting the DNA repair mechanism through epigenetic modulation involving genes of HMGB1, APEX1, and POLE3. Hence, we propose that CPT-CEF could be a DNA repair modulator that harnesses the cell's epigenomic plasticity to amend DNA repair deficiencies in cancer cells.


Assuntos
Antineoplásicos Fitogênicos/química , Camptotecina/química , Neoplasias do Colo/tratamento farmacológico , Reparo do DNA/efeitos dos fármacos , Nanopartículas Magnéticas de Óxido de Ferro/química , Nanocápsulas/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Sequência de Bases , Camptotecina/farmacologia , Linhagem Celular Tumoral , Ciclodextrinas/química , DNA Polimerase III/genética , DNA Polimerase III/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Composição de Medicamentos , Liberação Controlada de Fármacos , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica , Biblioteca Gênica , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Humanos , Nucleoproteínas/genética , Nucleoproteínas/metabolismo
17.
J Phys Chem B ; 125(40): 11112-11121, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34523939

RESUMO

Biological host molecules such as ß-cyclodextrins (ß-CDs) have been used to remove cholesterol guests from membranes and artery plaques. In this work, we calibrated the host-guest intermolecular mechanical forces (IMMFs) between cholesterol and cyclodextrin complexes by combining single-molecule force spectroscopy in optical tweezers and computational molecular simulations for the first time. Compared to native ß-CD, methylated beta cyclodextrins complexed with cholesterols demonstrated higher mechanical stabilities due to the loss of more high-energy water molecules inside the methylated ß-CD cavities. This result is consistent with the finding that methylated ß-CD is more potent at solubilizing cholesterols than ß-CD, suggesting that the IMMF can serve as a novel indicator to evaluate the solubility of small molecules such as cholesterols. Importantly, we found that the force spectroscopy measured in such biological host-guest complexes is direction-dependent: pulling from the alkyl end of the cholesterol molecule resulted in a larger IMMF than that from the hydroxyl end of the cholesterol molecule. Molecular dynamics coupled with umbrella sampling simulations further revealed that cholesterol molecules tend to enter or leave from the wide opening of cyclodextrins. Such an orientation rationalizes that cyclodextrins are rather efficient at extracting cholesterols from the phospholipid bilayer in which hydroxyl groups of cholesterols are readily exposed to the hydrophobic cavities of cyclodextrins. We anticipate that the IMMF measured by both experimental and computational force spectroscopy measurements help elucidate solubility mechanisms not only for cholesterols in different environments but also to host-guest systems in general, which have been widely exploited for their solubilization properties in drug delivery, for example.


Assuntos
Ciclodextrinas , beta-Ciclodextrinas , Colesterol , Interações Hidrofóbicas e Hidrofílicas , Solubilidade
18.
J Agric Food Chem ; 69(37): 11006-11014, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34491745

RESUMO

Many phytochemicals suffer from poor water dispersity and storage stability, which restrict their application within aqueous-based commercial products. ß-Cyclodextrin (ß-CD) is a water-dispersible molecule with a hydrophobic core that can encapsulate and protect non-polar substances. The functional attributes of ß-CD can be further enhanced by chemical modification. In this study, a simple and effective dry-heating process was applied to fabricate succinic acid (SA)-modified ß-CD (SACD) through esterification. SACD showed better encapsulation property than non-modified ß-CD to guest molecules such as methyl orange (up to 1.41-folds of ß-CD) and curcumin (with an encapsulation efficiency of up to 10 mg/g). Meanwhile, higher water solubility (up to 469.30 g per 100 g of H2O) was achieved for SACD, indicating that a high dose of SACD could be applied in an aqueous food matrix. Such a simple strategy exhibiting low cytotoxicity shows great potential incorporating bioactive compounds into functional foods.


Assuntos
Curcumina , Ciclodextrinas , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Água
19.
Int J Mol Sci ; 22(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34502331

RESUMO

Cyclodextrins (CDs) are highly respected for their ability to form inclusion complexes via host-guest noncovalent interactions and, thus, ensofance other molecular properties. Various molecular modeling methods have found their applications in the analysis of those complexes. However, as showed in this review, molecular dynamics (MD) simulations could provide the information unobtainable by any other means. It is therefore not surprising that published works on MD simulations used in this field have rapidly increased since the early 2010s. This review provides an overview of the successful applications of MD simulations in the studies on CD complexes. Information that is crucial for MD simulations, such as application of force fields, the length of the simulation, or solvent treatment method, are thoroughly discussed. Therefore, this work can serve as a guide to properly set up such calculations and analyze their results.


Assuntos
Ciclodextrinas/análise , Ciclodextrinas/química , Simulação de Dinâmica Molecular , Estrutura Molecular
20.
Chemistry ; 27(62): 15516-15527, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34523167

RESUMO

Host-guest complexes between native cyclodextrins (α-, ß- and γ-CD) and hybrid Lindqvist-type polyoxovanadates (POVs) [V6 O13 ((OCH2 )3 C-R)2 ]2- with R = CH2 CH3 , NO2 , CH2 OH and NH(BOC) (BOC = N-tert-butoxycarbonyl) were studied in aqueous solution. Six crystal structures determined by single-crystal X-ray diffraction analysis revealed the nature of the functional R group strongly influences the host-guest conformation and also the crystal packing. In all systems isolated in the solid-state, the organic groups R are embedded within the cyclodextrin cavities, involving only a few weak supramolecular contacts. The interaction between hybrid POVs and the macrocyclic organic hosts have been deeply studied in solution using ITC, cyclic voltammetry and NMR methods (1D 1 H NMR, and 2D DOSY, and ROESY). This set of complementary techniques provides clear insights about the strength of interactions and the binding host-guest modes occurring in aqueous solution, highlighting a dramatic influence of the functional group R on the supramolecular properties of the hexavanadate polyoxoanions (association constant K1:1 vary from 0 to 2 000 M-1 ) while isolated functional organic groups exhibit only very weak intrinsic affinity with CDs. Electrochemical and calorimetric investigations suggest that the driving force of the host-guest association involving larger CDs (ß- and γ-CD) is mainly related to the chaotropic effect. In contrast, the hydrophobic effect supported by weak attractive forces appears as the main contributor for the formation of α-CD-containing host-guest complexes. In any cases, the origin of driving forces is clearly related to the ability of the macrocyclic host to desolvate the exposed moieties of the hybrid POVs.


Assuntos
Ciclodextrinas , Cristalografia por Raios X , Interações Hidrofóbicas e Hidrofílicas , Conformação Molecular , Água
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