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1.
Chem Commun (Camb) ; 59(7): 896-899, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36594783

RESUMO

Coumarin acting as an optical probe was modified on ethylenediamine ß-cyclodextrin, which not only enhanced its molecular binding affinity to glutathione (GSH) by a reversible Michael addition, showing 113 times more affinity than that of coumarin itself, but also achieved dynamic real-time sensing of glutathione in living HeLa cells.


Assuntos
Corantes Fluorescentes , beta-Ciclodextrinas , Humanos , Células HeLa , Corantes Fluorescentes/química , Glutationa/química , Cumarínicos/química
3.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675035

RESUMO

The complexation of ß-cyclodextrin (ß-CD) with cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) was investigated using molecular docking and M062X/6-31G(d,p) calculations. The calculations suggested two possible complex formations of 1:1 and 2:1 host-guest molecular ratio of ß-CD with CBD and THC. The preferred orientation of all complexes in this study exhibited the hydrogen bonding between hydroxy-substituted benzene ring of CBD and THC with the ß-CD's secondary hydroxy groups at the wide rim. The calculated complexation energies indicate that formation of the 2:1 complexes (-83.53 to -135.36 kcal/mol) was more energetically favorable and chemically stable than the 1:1 complexes (-30.00 to -34.92 kcal/mol). However, the deformation energies of the host and the guest components in the 2:1 complexes (37.47-96.91 kcal/mol) are much higher than those in the 1:1 complexes (3.49-8.69 kcal/mol), which means the formation processes of the 2:1 complexes are more difficult due to the rigidity of the dimeric ß-CDs. Therefore, the inclusion complexes of ß-CD with CBD and THC are more likely to be in 1:1 host-guest ratio than in 2:1 molecular ratio. The results of this study supported the experimental results that the complexation constant of 1:1 ß-CD/CBD (Ks = 300 M-1) is greater than that of 2:1 ß-CDs/CBD (Kss = 0.833 M-1). Altogether, this study introduced the fitting parameters that could indicate the stability of the molecular fits in complex formation of each stoichiometry host-guest ratio, which are important for the assessment of the inclusion mechanisms as well as the relationships of reactants and products in chemical reactions.


Assuntos
Canabidiol , beta-Ciclodextrinas , Simulação de Acoplamento Molecular , Dronabinol , Teoria da Densidade Funcional , beta-Ciclodextrinas/química
4.
AAPS PharmSciTech ; 24(1): 48, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36702943

RESUMO

Clomiphene citrate is the first-line treatment for women with abnormal or failed ovulation. Currently, it is available as oral tablets, and the parenteral formulation does not exist. In this study, we prepared clomiphene citrate-hydroxypropyl-ß-cyclodextrin inclusion complex for its use in intravenous injection. The inclusion complex was characterized in the liquid state (phase solubility) and solid state by differential scanning calorimetry, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy analyses. The sterile intravenous injection containing 0.5% clomiphene citrate was prepared and characterized for its physical properties, assay, pH, and osmolality. A stability-indicating high-performance liquid chromatography (HPLC) method for the injection was developed. The HPLC method was validated for the assay, linearity, precision and repeatability, benchtop stability, and forced degradation to elute clomiphene isomers from the degradation products. The injection was packed in sterile 10-ml glass vials with butyl rubber stoppers and stored at 40°C, room temperature, and 4°C. The samples at 0, 0.5, 1, 2, 3, and 6 months were analyzed for clarity, pH, osmolality, and drug assay. The HPLC method was linear (R2 = 0.9999), precise (0.86% relative standard deviation), and stability indicating. The stability data at the accelerated (40°C) storage condition for 6 months showed satisfactory results: the drug assay in the injection was between 90 and 105%, the injection remained clear, pH was between 4.0 and 4.4, and osmolality was between 270 and 350 mOsm. The stability data suggests that the product is stable and meets the given analytical specifications.


Assuntos
beta-Ciclodextrinas , Feminino , Humanos , 2-Hidroxipropil-beta-Ciclodextrina/química , beta-Ciclodextrinas/química , Injeções Intravenosas , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Varredura Diferencial de Calorimetria , Estabilidade de Medicamentos
5.
Anal Chim Acta ; 1240: 340753, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36641148

RESUMO

The current research presents the evaluation of supramolecular proficiency of the designed platform for electrocatalytic determination of pernicious food colorants, amaranth and fast green. The approach involving surface modification of glassy carbon electrode with beta cyclodextrin decorated strontium ferrite reduced graphene oxide nanocomposite (SFrGO-ßCD) to ensure fast and reversible electro-oxidation of hydroxyl groups of the colorant molecules. The synergy between SF and rGO facilitated the sensor with enhanced surface area and conductivity through faradic redox reaction. Tremendous decrease in the obtained values of peak separation potential and impedance as manifested in CV and EIS analysis, enabled by electrostatic interactions between surface functionalities of rGO and ßCD has resulted in the significant augmentation of sensitivity. The value of charge transfer coefficient, number of electrons involved, nature of electron transport process at electrode electrolyte interface during the analysis of electrochemical detection were explored through CV experiments. Food samples analysis (without spiking) utilizing screen printed electrode manifested the sensor as portable device for real time monitoring. Outstanding detection limit (0.022 nM for amaranth and 0.051 nM for fast green), excellent regenerability (Relative standard deviation less than 3%) and apparent recovery rate (above 90%) of the modified electrode presented a colossal potential for the development of sustainable and commercially competitive electrochemical sensor in food sector.


Assuntos
Corantes de Alimentos , Grafite , beta-Ciclodextrinas , Limite de Detecção , Grafite/química , beta-Ciclodextrinas/química , Corante Amaranto , Técnicas Eletroquímicas/métodos , Eletrodos
6.
Talanta ; 253: 123959, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36208556

RESUMO

Simultaneous selective determination of Fe (Ⅱ) and Fe (Ⅲ) is of great significance to the study of iron ion tracking and release of iron supplement in gastric fluid. In this paper, a composite material (N-CQDs/AgNPs/ß-CD) was prepared by a one-pot method. The various characterizations confirmed the silver nanoparticles (AgNPs) grew in situ on the surface of nitrogen-doped carbon quantum dots (N-CQDs), and the ß-cyclodextrin (ß-CD) and AgNPs linked together by Ag-O bonds finally presented gourd-like nanoparticles on the surface of N-CQDs. Then, N-CQDs/AgNPs/ß-CD modified glassy carbon electrode (GCE) was applied to detect Fe(II) and Fe(III) simultaneously. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results confirmed that N-CQDs/AgNPs/ß-CD enhanced electrode performances because of the synergistic effect between N-CQDs, AgNPs and ß-CD. The sensor was successfully applied for the determination by differential pulse voltammetry (DPV) of Fe(II) and Fe(III) released from four iron supplementations in simulated gastric fluid (SGF).


Assuntos
Nanopartículas Metálicas , beta-Ciclodextrinas , Carbono , Nitrogênio , Compostos Férricos , Prata , Ferro , Compostos Ferrosos
7.
J Environ Sci (China) ; 126: 565-574, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36503782

RESUMO

Excessive consumption of energy and resources is a major challenge in wastewater treatment. Here, a novel heterogeneous Fenton-like catalyst consisting of Cu-doped graphene-like catalysts (Cu-GCD NSs) was first synthesized by an enhanced carbothermal reduction of ß-cyclodextrin (ß-CD). The catalyst exhibits excellent Fenton-like catalytic activity for the degradation of various pollutants under neutral conditions, accompanied by low H2O2 consumption. The results of structural characterization and theoretical calculations confirmed that the dual reaction centers (DRCs) were constructed on Cu-GCD NSs surface through C-O-Cu bonds supported on zero-valent copper species, which play a significant role in the high-performance Fenton-like reaction. The pollutants that served as electron donors were decomposed in the electron-poor carbon centers, whereas H2O2 and dissolved oxygen obtained these electrons in the electron-rich Cu centers through C-O-Cu bonds, thereby producing more active species. This study demonstrates that the electrons of pollutants can be efficiently utilized in Fenton-like reactions by DRCs on the catalyst surface, which provides an effective strategy to improve Fenton-like reactivity and reduce H2O2 consumption.


Assuntos
Poluentes Ambientais , Purificação da Água , beta-Ciclodextrinas , Polímeros , Elétrons , Peróxido de Hidrogênio
8.
Plant Physiol Biochem ; 194: 570-575, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36525938

RESUMO

Chitosan is a polycationic polysaccharide derived from chitin, and ß-cyclodextrin is a type of macrocyclic oligosaccharide linked by α-1,4 glycosidic bonds. These compounds are recognized as effective elicitors in the biosynthesis of secondary metabolites in plants. These elicitors were studied to assess the growth of shoots and the synthesis of glucosinolates (GSLs) from elicited shoots in Chinese cabbage under controlled in vitro conditions for the first time. Chitosan at 150 mg L-1 supplemented in the optimized shoot induction recovered maximum quantities of total GSLs (7.344 µmol g-1 DW) at the end of 5th week of culture duration, followed by ß-cyclodextrin (15 mg L-1) with the synthesis of GSLs (6.379 µmol g-1 DW) at the end of 4th week of culture. The application of chitosan completely deteriorated the growth of shoots, whereas ß-cyclodextrin did not affect and even increased the growth of shoots (4.66 g DW). Upon elicitation, the individual got GSLs contents exhibited various fold changes (1.78-to-23.5-fold). Real-time PCR analysis of essential GSLs biosynthesis genes like MAM1, ST5b, AOP2, FMOGS-OX1, CYP83B1, CYP81F2, ST5a, and CYP81F4 revealed substantial higher expression upon elicitation. This present study would provide a steady production of GSLs in Chinese cabbage shoots with the influence of carbohydrate-based elicitors for pharmaceutical or food companies in the future.


Assuntos
Brassica rapa , Brassica , Quitosana , beta-Ciclodextrinas , Brassica rapa/metabolismo , Glucosinolatos , Quitosana/farmacologia , Quitosana/metabolismo , Brassica/genética , beta-Ciclodextrinas/farmacologia
9.
Int J Pharm ; 631: 122497, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36529360

RESUMO

The extract obtained from Mikania glomerata leaves rich in ent-kaurenoic acid (ERKA) shows cytotoxic activity in vitro, but its hydrophobic nature and thermosensitivity are issues to be solved prior to in vivo antitumor studies. The purpose of this study was to investigate the antitumor activity of inclusion complexes formed between ERKA and ß-cyclodextrin (ERKA:ß-CD) in rodents. ERKA:ß-CD complexes obtained by malaxation (MX) and co-evaporation (CE) methods were firstly characterized regarding their physical properties, encapsulation efficiency, and cytotoxicity againts L929 cells. The antitumor activity study was then performed in mice with sarcoma 180 treated with saline, 5-fluouracil (5FU) and ERKA:ß-CD at 30, 100 and 300 µg/kg. The weight, volume, percentage of inhibition growth, gross and pathological features and positivity for TUNEL, ki67, NFκB and NRF2 in the tumors were assessed. Serum lactate-dehydrogenase activity (LDH), white blood cells count (WBC) and both gross and pathological features of the liver, kidneys and spleen were also evaluated. The formation of the inclusion complexes was confirmed by thermal analysis and FTIR, and they were non-toxic for L929 cells. The MX provided a better complexation efficiency. ERKA:ß-CD300 promoted significant tumor growth inhibition, and attenuated the tumor mitotic activity and necrosis content, comparable to 5-fluorouracil. ERKA:ß-CD300 also increased TUNEL-detected cell death, reduced Ki67 and NF-kB immunoexpression, and partially inhibited the serum LDH activity. No side effect was observed in ERKA:ß-CD300-treated animals. The ERKA:ß-CD inclusion complexes at 300 µg/kg displays antitumour activity in mice with low systemic toxicity, likely due to inhibition on the NF-kB signaling pathway and LDH activity.


Assuntos
Mikania , Neoplasias , Sarcoma 180 , beta-Ciclodextrinas , Camundongos , Animais , Mikania/química , Sarcoma 180/tratamento farmacológico , NF-kappa B , Antígeno Ki-67 , beta-Ciclodextrinas/química , Desenvolvimento de Medicamentos
10.
Talanta ; 255: 124219, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36580809

RESUMO

Nanozyme with the merit of excellent and adjustable catalytic activity, outstanding stability and low cost is a promising alternative for natural enzymes widely applied in a variety of fields. In the present study, a new two-dimensional cobalt-based MOF nanocomposite designated as MVCM@ß-CD was synthesized. Combined with the strategies of increasing the ratio of Co(Ⅲ)/Co(Ⅱ) and modifying with small molecule ß-cyclodextrin (ß-CD), MVCM@ß-CD displayed remarkably enhanced oxidase-mimicking activity, which was attributed to synergistic effect from large surface area of two dimensional Co-MOF nanosheet, numerous exposed active sites, high-proportioned trivalence of cobalt and regulating action of ß-cyclodextrin. The addition of aminophenol isomers inhibited the catalytic oxidation process, resulting in different color change of the solution and UV-Vis absorption behaviors, based on which a sensitive ratiometric colorimetry for m-aminophenol (m-Ap) and a simple colorimetric p-aminophenol (p-Ap) detection method were developed with the detection limit of 0.16 µM and 1.01 µM, respectively. This method realized the colorimetric differentiation of aminophenol isomers, which provided a simple, accurate and low-cost approach for visual discrimination without complicated instrument and procedure, especially appropriate for on-site detection.


Assuntos
Oxirredutases , beta-Ciclodextrinas , Oxirredutases/química , Colorimetria/métodos , Aminofenóis , Cobalto/química
11.
Soft Matter ; 19(3): 342-346, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36541262

RESUMO

Amphiphilic alkyl-perylenebisdiimide-DNA hybrids self-assemble into spherical micelles and transform into nanofibers upon the addition of ß-cyclodextrins due to host-guest interaction. A competitive guest can induce the nanofibers to reversibly change back to spherical micelles. Both spherical micelles and nanofibers can anchor functional molecules at the corona through DNA hybridization.


Assuntos
Ciclodextrinas , Nanofibras , beta-Ciclodextrinas , Micelas , DNA
12.
Langmuir ; 39(1): 638-646, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36542801

RESUMO

Although paraquat is a widely used herbicide, it is toxic to humans if ingested or absorbed through an open wound. To improve the safety of paraquat, a new formulation of paraquat based on photoresponsive polymers was exploited. Photoresponsive ß-cyclodextrin polymer microspheres (AZO-CD) were synthesized via a host-guest interaction between ß-cyclodextrin and azobenzene. AZO-CD were characterized by Fourier transform infrared spectrometry, circular dichroism, ultraviolet (UV) spectrophotometry, and thermogravimetric analysis, and their photoresponsiveness was also evaluated. AZO-CD were used to load paraquat, which yielded photoresponsive paraquat-loaded microspheres. For the paraquat-loaded microspheres, irradiation with UV light or sunlight induced the isomerization of azobenzene into the cis form. Then, the cis-azobenzene was liberated from the cavities of the ß-cyclodextrin. The paraquat-loaded microspheres released paraquat continuously over time. Furthermore, under UV light, the herbicidal capacity of the paraquat-loaded microspheres against barnyard grass was comparable to that of free paraquat at the same dose. Our findings show that loading paraquat into AZO-CD provides a safe and environmentally friendly herbicide formulation.


Assuntos
Herbicidas , beta-Ciclodextrinas , Humanos , Paraquat/toxicidade , Microesferas , beta-Ciclodextrinas/química , Compostos Azo/química , Polímeros/química
13.
Chemosphere ; 287(Pt 4): 132373, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34600005

RESUMO

Monitoring of pathogenic bacteria plays a vital role in precluding foodborne disease outbreaks. In this research work, a genosensor based on innovative label-free DNA was developed for the detection of Salmonella. typhimurium (S. typhimurium) in the milk samples. To realize this objective, bimetallic Fe/Mn MOF is synthesized and mixed with methyl-ß-cyclodextrin (MßCD) and AuNPs which are then stabilized on multi-walled carbon nanotubes (MWCNTs), and the obtained nanocomposite is immobilized on the Au electrode surface. Different characterization methods such as FE-SEM, TEM, EDS, FTIR, and XRD were used for investigating the particle size and morphological features. Electrochemical and impedimetric techniques were used for exploring the applicability of the fabricated genosensor. Under optimal circumstances, LOD and LOQ have acquired at 0.07 pM and 0.21 pM. Moreover, an extensive linear range of 1 pM-1 µM was resulted for ss-tDNA (single-stranded target DNA), R2 obtained 0.9991. The recoveries were obtained 95.6-104%. Great selectivity against one, two, and three-base mismatched sequences was also shown for fabricated biosensing assay. Furthermore, negative genosensing assay control for investigating selectivity was provided by the ss-tDNAs of Haemophilusinfluenzae and Shigella dysenteriae bacteria. Well-fabricated genosensing bio-assay represents better performance, great specificity, high sensitivity, increased active sites, and finally results in an increase in the electron transfer rate. It is to be noted that the organized genosensing bio-assay is capable of being re-used and re-generated in a straightforward manner to estimate the hybridization process.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanotubos de Carbono , Animais , DNA , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Leite , Salmonella typhimurium/genética , beta-Ciclodextrinas
14.
Pak J Pharm Sci ; 35(5): 1415-1422, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36451572

RESUMO

The aim of this study was to improve the solubility of aripiprazole (ARP) by fabricating binary and ternary inclusion complexes with methyl-ß-cyclodextrin (MßCD) and L-Arginine (LA). Physical mixing and lyophilization were used in the following molar ratios: 1:1, 1:2.5, 1:4, 1:9, 1:1:1, 1:1:0.27, 1:4:1, 1:9:1, 1:3.6:3.6. The developed formulations were analyzed by solubility and dissolution. They were characterized by FTIR, XRD, DSC, SEM and TGA. Ternary formulations prepared by the lyophilization method showed improved dissolution rates in simulated gastric fluid (SGF). The results showcased that the addition of MßCD and LA in inclusion complexes enhanced the solubility and decreased crystallinity. The amorphous nature of Aripiprazole in lyophilization was confirmed by XRD diffractograms. Drug release was dominated by the first-order kinetics (R2 = 0.9932) with the Fickian type of diffusion mechanism (n<0.450). LY18, LY19, LY20 and LY21 have the highest solubility (30, 35, 43 and 48 times higher than the pure drug respectively). Furthermore, it was observed that the method of preparation, as well as a specific drug to polymer and amino acid ratio, are critical for achieving high drug solubility and stability. These complexes appeared to be a promising product for the development of new drug delivery systems.


Assuntos
beta-Ciclodextrinas , Solubilidade , Aripiprazol , Arginina
15.
Biomolecules ; 12(12)2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36551190

RESUMO

Piperine (PN), the primary pungent alkaloid in black pepper shows several biological activities such as antioxidant, antimicrobial and anti-cancerogenic effects. Similar to other alkaloids, PN is characterized by poor water solubility. One way to improve its solubility and thus its biological activities is by forming inclusion complexes with suitable cyclodextrins. In this work PN inclusion complexes in native ß-cyclodextrin (ß-CD), its methylated (randomly methylated (RM-ß-CD), heptakis-(2,6-di-O-methyl)-ß-CD (DM-ß-CD) and heptakis-(2,3,6-tri-O-methyl)-ß-CD (TM-ß-CD)) and 2-hydroxypropylated (HP-ß-CD) derivatives are investigated using physicochemical methods, such as phase solubility study and X-ray crystallography complemented by theoretical (molecular dynamics simulations) studies. The determination of the crystal structure of the PN inclusion complexes in ß-CD, DM-ß-CD and TM-ß-CD, reveals the formation of 1:2 guest:host inclusion complexes in the crystalline state. The guest PN molecule threads the hydrophobic cavities of the hosts which are arranged as couples in a tail-to-tail mode in the case of PN/ß-CD and in a head-to-tail mode in the cases of PN/DM-ß-CD and PN/TM-ß-CD. MD studies based on the crystallographically determined structures and docked models show the stability of the examined complexes in an aqueous environment whereas the binding affinity of PN for the host molecules is calculated by the MM/GBSA method. Finally, phase-solubility studies of PN with ß-CD, RM-ß-CD and HP-ß-CD are presented, indicating a Bs-type for the PN/ß-CD complex and an AL-type for the PN/RM-ß-CD and PN/HP-ß-CD complexes with 1:1 guest:host stoichiometry.


Assuntos
Alcaloides , Ciclodextrinas , beta-Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina , beta-Ciclodextrinas/química , Ciclodextrinas/química , Solubilidade
16.
J Phys Chem Lett ; 13(51): 11990-11995, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36537879

RESUMO

The effect of the density of active molecules in molecular junctions (MJs) has been investigated by using a host/guest strategy. Mixed layers consisting of oligothiophene (BTB) encapsulated by ß-cyclodextrin (BTB@ß-CD) were generated. Cyclodextrins were then removed, and the pinholes generated were filled with BTB to obtain BTB@BTB films. MJs based on mixed BTB@ß-CD and BTB@BTB layers, as well as single-component BTB MJs, were compared. The variation of ln J vs thickness is similar for all systems while the Jo of BTB@ß-CD MJs is 20 times lower than that of BTB MJs. After ß-cyclodextrin has been removed, and the pinholes filled, Jo increases and reaches the same value as for the BTB MJs, showing that the conductance scales with the number of active molecules. This strategy provides a unique method for investigating molecular interactions in direct tunneling MJs as well as the possibility of fabricating new functionalized MJs based on mixed layers.


Assuntos
Ciclodextrinas , beta-Ciclodextrinas
17.
Int J Mol Sci ; 23(24)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36555759

RESUMO

Gemfibrozil (GEM) is a hypolipidemic agent, which is effective in reducing serum cholesterol and triglyceride levels. Complexation of GEM with native ß-cyclodextrin (ß-CD) and with the derivatives hydroxypropyl-ß- and randomly methylated ß-CD (HPß-CD and Meß-CD) was studied in aqueous solution of pH 2.8 and 7.0. The stability constants were determined by spectrofluorimetry, 1H-NMR spectroscopy and solubility assays. Considering the well-known difficulties to obtain similar stability constants by different techniques, the agreement of the values obtained supports the reliability of the results presented. The advantages and drawbacks of each analytical technique for the study of inclusion complexation were discussed as well. In addition, the thermodynamic parameters of complexation, enthalpy (ΔH) and entropy (ΔS), were determined and related to the type of molecular interactions that take place between GEM and the different cyclodextrins. Finally, solid dispersions were prepared by co-evaporation, kneading, vacuum desiccation, and coprecipitation, and complexation was evaluated by X-ray diffraction.


Assuntos
Ciclodextrinas , beta-Ciclodextrinas , Genfibrozila , 2-Hidroxipropil-beta-Ciclodextrina , Reprodutibilidade dos Testes , beta-Ciclodextrinas/química , Ciclodextrinas/química , Solubilidade , Difração de Raios X
18.
Int J Mol Sci ; 23(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36499470

RESUMO

Purine nucleosides represent an interesting group of nitrogen heterocycles, showing a wide range of biological effects. In this study, we designed and synthesized a series of 6,9-disubstituted and 2,6,9-trisubstituted purine ribonucleosides via consecutive nucleophilic aromatic substitution, glycosylation, and deprotection of the ribofuranose unit. We prepared eight new purine nucleosides bearing unique adamantylated aromatic amines at position 6. Additionally, the ability of the synthesized purine nucleosides to form stable host-guest complexes with ß-cyclodextrin (ß-CD) was confirmed using nuclear magnetic resonance (NMR) and mass spectrometry (ESI-MS) experiments. The in vitro antiproliferative activity of purine nucleosides and their equimolar mixtures with ß-CD was tested against two types of human tumor cell line. Six adamantane-based purine nucleosides showed an antiproliferative activity in the micromolar range. Moreover, their effect was only slightly suppressed by the presence of ß-CD, which was probably due to the competitive binding of the corresponding purine nucleoside inside the ß-CD cavity.


Assuntos
Adamantano , beta-Ciclodextrinas , Humanos , Adamantano/farmacologia , Nucleosídeos de Purina/farmacologia , Nucleosídeos de Purina/metabolismo , beta-Ciclodextrinas/farmacologia , Linhagem Celular Tumoral , Nucleosídeos/farmacologia , Nucleosídeos/química
19.
Mikrochim Acta ; 190(1): 33, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36538097

RESUMO

A novel sandwich electrochemical impedimetric immunosensor was proposed to detect apolipoprotein-A1 (Apo-A1), a common biomarker for bladder cancer. The molybdenum disulfide/graphene quantum dot (MoS2/GQD) nanocomposites were modified on the surface of a glassy carbon electrode (GCE) and used to immobilize the biotinylated antibody (Ab1) with the help of chitosan and glutaraldehyde (denoted as BSA/Ab1/CHIT/MoS2/GQD/GCE). Pb(II)-thiol-ß-cyclodextrin metal-organic framework (denoted as Pb-MOF) was synthesized with lead metal ions and thiol-ß-cyclodextrin ligands by a one-pot solvothermal method, and then, gold nanoparticles were modified on the surface of Pb-MOF (Pb-MOF-AuNPs) by Au-S bond, which was used as signal label for the recombinant antibody (Ab2). When the immunosensor of BSA/Ab1/CHIT/MoS2/GQD/GCE reacted with Apo-A1, Pb-MOF-AuNPs-Ab2/BSA was connected to the electrode when immunoreaction occurred, and an immune sandwich structure was formed, which led to significantly increased charge transfer resistance of electrochemical probe for ferrocyanide (II)/(III) within the frequency range 10-1 ~ 105 Hz at 5 mV amplitude and the potential of 0.180 V (vs. SCE). Based on this principle, the quantitative detection of Apo-A1 was established. The relative change of electrochemical resistance and the logarithmic value of Apo-A1 concentration showed a linear relationship with a linear coefficient of 0.9989 in the range 1.00 pg mL-1 and 1.00 µg mL-1 with the limit of detection of 0.30 pg mL-1. The selectivity, repeatability, and other performance of the proposed immunosensor were also investigated. The immunosensor was successfully applied to the detection of real serum and urine samples with recovery in the range 96.4 ~ 109.1% (RSD < 3.8%), indicating that it could be helpful for the clinical diagnosis of bladder cancer.


Assuntos
Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Estruturas Metalorgânicas , beta-Ciclodextrinas , Ouro/química , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Molibdênio/química , Chumbo , Técnicas Biossensoriais/métodos , Imunoensaio/métodos , Grafite/química , Carbono , Apolipoproteínas
20.
Sci Rep ; 12(1): 19106, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36352247

RESUMO

This manuscript reports an impressive and facile strategy for synthesizing isoxazole derivatives using immobilized Cu (I) in metformin-functionalized ß-cyclodextrin as a catalyst. The architecture of this catalyst was characterized by different analytical techniques such as Fourier transform infrared spectroscopy, Thermogravimetric analysis, X-ray diffraction, Field emission scanning electron microscopy, and Energy-dispersive X-ray spectroscopy. The catalyst showed remarkable reusability even after 7 consecutive runs.


Assuntos
Isoxazóis , beta-Ciclodextrinas , Catálise , beta-Ciclodextrinas/química , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier
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