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1.
J Comput Chem ; 45(16): 1329-1351, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38372509

RESUMO

In this study, the enantioselectivity of ß-cyclodextrin and its derivatives towards propranolol enantiomers are investigated by molecular dynamic (MD) simulations. ß-cyclodextrin (ß-CD) have previously been shown to be able to recognize propranolol (PRP) enantiomers. To improve upon the enantioselectivity of ß-cyclodextrin, we propose the use of an ionic-liquid-modified-ß-cyclodextrin (ß-CD-IL). ß-CD-IL was found to be able to complex R and S propranolol enantiomers with differing binding energies. The molecular docking study reveals that the ionic liquid chain attached to the ß-CD molecule has significant interaction with propranolol. The formation of the most stable complex occurred between (S)-ß-CD-IL and (S)-propranolol with an energy of -5.80 kcal/mol. This is attributed to the formation of a hydrogen bond between the oxygen of the propranolol and the hydrogen on the primary rim of the (S)-ß-CD-IL cavity. This interaction is not detected in other complexes. The root mean-squared fluctuation (RMSF) value indicates that the NH group is the most flexible molecular fragment, followed by the aromatic group. Also of note, the formation of a complex between pristine ß-CD and (S)-propranolol is the least favorable.

2.
J Comput Chem ; 45(25): 2112-2118, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-38760972

RESUMO

The regioselective radical CH trifluoromethylation of aromatic compounds have been shown to proceed in good yield and high regioselectivity when cyclodextrin (CD) is present. Yet, the reaction mechanism and the role of CD during the reaction have remained obscure. To this end, here we performed density functional theory (DFT) calculations to the conformations obtained by semiempirical quantum mechanical molecular dynamics calculations to reveal the reaction mechanism and the role of CD in controlling regioselectivity. The results show that metal salt increases the yield but do not affect the regioselectivity, which we further confirmed by an experiment. In contrast, multiple CD-substrate complex conformations and reaction pathways were obtained, and CD was shown to contribute to improving the regioselectivity by stabilizing the intermediate state via encapsulation. The present study indicates that CDs can increase the regioselectivity by stabilizing the intermediate and product states while only marginally affecting the transition state.

3.
Biol Proced Online ; 26(1): 3, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38279106

RESUMO

BACKGROUND: Generating targeted mutant mice is a crucial technology in biomedical research. This study focuses on optimizing the CRISPR/Cas9 system uptake into sperm cells using the methyl ß-cyclodextrin-sperm-mediated gene transfer (MBCD-SMGT) technique to generate targeted mutant blastocysts and mice efficiently. Additionally, the present study elucidates the roles of cholesterol and reactive oxygen species (ROS) in the exogenous DNA uptake by sperm. RESULTS: In this study, B6D2F1 mouse sperm were incubated in the c-TYH medium with different concentrations of MBCD (0, 0.75, 1, and 2 mM) in the presence of 20 ng/µl pCAG-eCas9-GFP-U6-gRNA (pgRNA-Cas9) for 30 min. Functional parameters, extracellular ROS, and the copy numbers of internalized plasmid per sperm cell were evaluated. Subsequently, in vitro fertilization (IVF) was performed and fertilization rate, early embryonic development, and transfection rate were assessed. Finally, our study investigated the potential of the MBCD-SMGT technique in combination with the CRISPR-Cas9 system, referred to as MBCD-SMGE (MBCD-sperm-mediated gene editing), for generating targeted mutant blastocysts and mice. Results indicated that cholesterol removal from the sperm membrane using MBCD resulted in a premature acrosomal reaction, an increase in extracellular ROS levels, and a dose-dependent influence on the copy numbers of the internalized plasmids per sperm cell. Moreover, the MBCD-SMGT technique led to a larger population of transfected motile sperm and a higher production rate of GFP-positive blastocysts. Additionally, the current study validated the targeted indel in blastocyst and mouse derived from MBCD-SMGE technique. CONCLUSION: Overall, this study highlights the significant potential of the MBCD-SMGE technique for generating targeted mutant mice. It holds enormous promise for modeling human diseases and improving desirable traits in animals.

4.
Small ; 20(32): e2311166, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38693075

RESUMO

Thermoresponsive nanogels (tNGs) are promising candidates for dermal drug delivery. However, poor incorporation of hydrophobic drugs into hydrophilic tNGs limits the therapeutic efficiency. To address this challenge, ß-cyclodextrins (ß-CD) are functionalized by hyperbranched polyglycerol serving as crosslinkers (hPG-ßCD) to fabricate ßCD-tNGs. This novel construct exhibits augmented encapsulation of hydrophobic drugs, shows the appropriate thermal response to dermal administration, and enhances the dermal penetration of payloads. The structural influences on the encapsulation capacity of ßCD-tNGs for hydrophobic drugs are analyzed, while concurrently retaining their efficacy as skin penetration enhancers. Various synthetic parameters are considered, encompassing the acrylation degree and molecular weight of hPG-ßCD, as well as the monomer composition of ßCD-tNGs. The outcome reveals that ßCD-tNGs substantially enhance the aqueous solubility of Nile Red elevating to 120 µg mL-1 and augmenting its dermal penetration up to 3.33 µg cm-2. Notably, the acrylation degree of hPG-ßCD plays a significant role in dermal drug penetration, primarily attributed to the impact on the rigidity and hydrophilicity of ßCD-tNGs. Taken together, the introduction of the functionalized ß-CD as the crosslinker in tNGs presents a novel avenue to enhance the efficacy of hydrophobic drugs in dermatological applications, thereby offering promising opportunities for boosted therapeutic outcomes.


Assuntos
Glicerol , Interações Hidrofóbicas e Hidrofílicas , Nanogéis , Polímeros , beta-Ciclodextrinas , beta-Ciclodextrinas/química , Glicerol/química , Nanogéis/química , Polímeros/química , Animais , Polietilenoimina/química , Reagentes de Ligações Cruzadas/química , Temperatura , Absorção Cutânea , Pele/metabolismo , Polietilenoglicóis/química , Oxazinas
5.
Small ; : e2405337, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073234

RESUMO

Transparent materials are widely used in industries, everyday life, and scientific activities. The development of new, lightweight, and durable artificial transparent materials is a challenge in synthetic chemistry. In this study, a supramolecular approach is conceived to construct transparent glass. Cyclodextrins are selected as the building blocks for the fabrication of supramolecular glass via noncovalent polymerization. The newly formed glass displays several attractive advantages, including good thermal processability, high mechanical strength and dielectric constant, excellent visible light transparency, and good adhesion performance. Importantly, the structural characteristics of long-range disorder and short-range order are observed in cyclodextrin glass. Here a new strategy is presented for the preparation and functionalization of low-molecular-weight transparent materials.

6.
Small ; 20(29): e2310217, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38361221

RESUMO

In this work, multi-layer Ti3C2 - carbon nanotubes - gold nanoparticles (Ti3C2-CNTs-Au) and cyclodextrin metal-organic framework - carbon nanotubes (CD-MOF-CNTs) have been prepared by in situ growth method and used to construct the ultra-sensitive rutin electrochemical sensor for the first time. Among them, the large number of metal active sites of Ti3C2, the high electron transfer efficiency of CNTS, and the good catalytic properties of AuNPs significantly enhance the electrochemical properties of the composite carbon nanomaterials. Interestingly, CD-MOF has a unique host-guest recognition and a large number of cavities, molecular gaps, and surface reactive groups, which gives the composite outstanding accumulation properties and selectivity for rutin. Under the optimized conditions, the constructed novel sensor has satisfactory detection performance for rutin in the range of 2 × 10-9 to 8 × 10-7 M with a limit of detection of 6.5 × 10-10 M. In addition, the sensor exhibits amazing anti-interference performance against rutin in some flavonoid compounds and can be used to test natural plant samples (buckwheat, Cymbopogon distans, and flos sophorae immaturus). This work has promising applications in the field of environmental and food analysis, and exploring new directions for the application of Mxene-based composites.


Assuntos
Ciclodextrinas , Ouro , Nanotubos de Carbono , Rutina , Titânio , Rutina/química , Rutina/análise , Ouro/química , Ciclodextrinas/química , Nanotubos de Carbono/química , Titânio/química , Estruturas Metalorgânicas/química , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos
7.
Small ; 20(29): e2400399, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38607266

RESUMO

To address the issue of bacterial growth on fresh-cut fruits, this paper reports the synthesis of nanosized γ-cyclodextrin metal-organic frameworks (CD-MOFs) using an ultrasound-assisted method and their application as carriers of limonene for antibacterial active packaging. The effects of the processing parameters on the morphology and crystallinity of the CD-MOFs are investigated, and the results prove that the addition of methanol is the key to producing nanosized CD-MOFs. The limonene loading content of the nanosized CD-MOFs can reach approximately 170 mg g-1. The sustained-release behaviors of limonene in the CD-MOFs are evaluated. Molecular docking simulations reveal the distribution and binding sites of limonene in the CD-MOFs. CD-MOFs are deposited on the surfaces of polycaprolactone (PCL) nanofibers via an immersion method, and limonene-loaded CD-MOF@PCL nanofibers are prepared. The morphology, crystallinity, thermal stability, mechanical properties, and antibacterial activity of the nanofibers are also studied. The nanofiber film effectively inhibits bacterial growth and prolongs the shelf life of fresh-cut apples. This study provides a novel strategy for developing antibacterial active packaging materials based on CD-MOFs and PCL nanofibers.


Assuntos
Frutas , Limoneno , Estruturas Metalorgânicas , Nanofibras , Poliésteres , gama-Ciclodextrinas , Limoneno/química , Limoneno/farmacologia , Nanofibras/química , Poliésteres/química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , gama-Ciclodextrinas/química , Frutas/química , Terpenos/química , Terpenos/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Simulação de Acoplamento Molecular
8.
Chembiochem ; : e202400396, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775269

RESUMO

The influence of alpha-cyclodextrin (αCD) on PEG crystallization is examined for a peptide-PEG conjugate, YYKLVFF-PEG3k comprising an amyloid peptide YYKLVFF linked to PEG with molar mass 3 kg mol-1. Remarkably, differential scanning calorimetry (DSC) and simultaneous synchrotron small-angle/wide-angle X-ray scattering (SAXS/WAXS) show that crystallization of PEG is suppressed by αCD, provided that the cyclodextrin content is sufficient. A hexagonal mesophase is formed instead. The αCD threading reduces the conformational flexibility of PEG, and hence suppresses crystallization. These results show that addition of cyclodextrins can be used to tune the crystallization of peptide-polymer conjugates and potentially other polymer/biomolecular hybrids.

9.
Electrophoresis ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576224

RESUMO

This research focuses on the development and validation of a capillary electrophoresis (CE) method for the chiral separation of three H1-antihistamine drugs chlorcyclizine, norchlorcyclizine, and neobenodine using sulfated ß-cyclodextrin (S-ß-CD) as the chiral selector. The study explores various factors influencing the separation efficiency, including CD concentration, organic modifier content, voltage application, and buffer pH. Optimal conditions were identified as a 100 mM phosphate buffer (pH 6.0) with 34 mg mL-1 S-ß-CD and 40% (v/v) methanol. The method demonstrated excellent linearity in calibration curves, with coefficients of determination exceeding 0.99 for each enantiomer. Precision studies revealed good intra- and inter-day precision for migration times and peak areas. The limits of detection and quantification for the analytes were within the ranges of 5.9-11.4 and 18-34.6 µmol L-1, respectively. Overall, the developed CE method offers a robust and precise approach for the chiral separation of H1-antihistamine drugs, holding promise for pharmaceutical applications.

10.
Chemistry ; 30(12): e202303984, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38127103

RESUMO

In recent decades, many efforts have been devoted to studying reactions catalyzed in nanoconfined spaces. The most impressive aspect of catalysis in nanoconfined spaces is that the reactivity of the molecules can be smartly driven to disobey classical behavior. A green and efficient three-component aza-Darzens (TCAD) reaction using a catalytic amount of γ-cyclodextrins (CDs) in water has been developed to synthesize N-phenylaziridines. CDs effectively performed this reaction in an environmentally friendly setting, achieving good yields. The same reaction was then performed using polymeric γ-CD such as a γ-cyclodextrin polymer crosslinked (GCDPC) with epichlorohydrin, a sponge-like macroporous γ-cyclodextrin-based cryogel (GCDC), and a γ-cyclodextrin-based hydrogel (GCDH). The homogeneous and heterogeneous catalyst recovery was then studied, and it was proved to be easily recycled several times without relevant activity loss. Water, as a unique and eco-friendly reaction medium, has been utilized for the first time, to the best of our knowledge, in this reaction. The inclusion of the reagents in CDs has been studied and rationalized by NMR spectroscopy experiments and molecular modeling calculations. The credit of the presented protocol includes good yields and catalyst reusability and precludes the use of organic solvents.

11.
Chemistry ; : e202402438, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39022852

RESUMO

Photosynthesis is a complex multi-step process in which light collection is the initial step of photosynthesis and plays an important role in the efficiency of solar energy utilization. In order to improve the utilization of sunlight, researchers have developed a variety of artificial light-harvesting system to simulate photosynthesis in nature. Here, we report a supramolecular self-assembly artificial light-harvesting system in aqueous solution.  We modified ß-CD with the donor molecule naphthalimide and adamantane with the tetraphenylethylene molecule which has aggregation-induced emission effects (AIE). By using fluorescent molecules with AIE, the self-quenching effect caused by aggregation in aqueous solution can be effectively avoided. Due to the host-guest interaction of ß-CD and adamantane, nanoparticles with stable structure and uniform size can be spontaneously assembled in water. Because of the close distance and strong spectral overlap between naphthalimide and tetraphenylethylene, Förster resonance energy transfer (FRET) was realized, and artificial light-harvesting system was successfully constructed in aqueous solution. The light-harvesting system has a high energy transfer efficiency (ΦET). Therefore, this study provides a new strategy for constructing artificial light-harvesting system.

12.
Mol Pharm ; 21(5): 2383-2393, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38551360

RESUMO

Nanocone clusters (NCCs) have been developed as clusters with inclusion complexes of FDA-approved ß-cyclodextrin (ßCD) and perfluorocarbons (PFC) (i.e., perfluoropentane (PFP) and perfluorohexane (PFH)) and have shown promise in nanoparticle-mediated histotripsy (NMH) applications owing to their lowered cavitation threshold, ease of production, and fluorocarbon quantification. However, there is still a lack of information on the best conditions of the synthesis of NCCs as a product that can have a maximum determinable fluorocarbon content and maintain the stability of the NCC during synthesis and when used as histotripsy agents or exposed to physiological conditions. These concerns about the stability of the clusters and the best possible formulation are investigated in the current work. The cluster formation potential was tested taking into consideration the nature of both PFCs and ßCD by employing different synthesis conditions in terms of solution and environmental parameters such as concentration of solvent, stoichiometry between ßCD and PFCs, temperature, pH, solvent type, etc. The best route of synthesis was then translated into various batch sizes and investigated in terms of the PFC loading and yield. These studies revealed that preparing NCCs in double-distilled water in an ice bath at the optimized solution concentration gave the highest yields and optimal PFC loading, as determined from gas chromatography. Furthermore, the stability of the clusters with different stoichiometries was scrutinized in varying concentrations, mechanical disruption times, pH levels, and temperature conditions, showing effects on each cluster's particle size in dynamic light scattering, visualized in transmission electron microscopy, and cavitation behavior in agarose gel tissue phantoms. These studies revealed stable clusters for all formulations, with PFH-containing NCCs emerging to be the most stable in terms of their cluster size and bubble formation potential in histotripsy. Finally, the shelf life of these clusters was investigated using DLS, which revealed a stable cluster. In conclusion, NCCs have shown high stability in terms of both synthesis, which can be replicated in gram-level production, and the cluster itself, which can be exposed to harsher conditions and still form stable bubbles in histotripsy.


Assuntos
Fluorocarbonos , Nanopartículas , beta-Ciclodextrinas , Fluorocarbonos/química , beta-Ciclodextrinas/química , Nanopartículas/química , Solventes/química , Temperatura , Concentração de Íons de Hidrogênio , Pentanos
13.
Mol Pharm ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39105761

RESUMO

Folate uptake is largely mediated by folate receptor (FR)ß, encoded by FOLR2 gene, in myeloid immune cells such as granulocytes, monocytes, and especially in macrophages that constitute the reticuloendothelial system (RES) and infiltrate the tumor microenvironment. Since the myeloid immune compartment dynamically changes during tumorigenesis, it is critical to assess the infiltration status of the tumors by FRß-expressing myeloid cells to better define the targeting efficacy of folate-functionalized drug delivery systems. On the other hand, clearance by RES is a major limitation for the targeting efficacy of nanoparticles decorated with folate. Therefore, the aims of this study are (i) to determine the amount and subtypes of FRß+ myeloid cells infiltrating the tumors at different stages, (ii) to compare the amount and subtype of FRß+ myeloid cells in distinct organs of tumor-bearing and healthy animals, (iii) to test if the cancer-targeting efficacy and biodistribution of a prototypic folate-functionalized nanoparticle associates with the density of FRß+ myeloid cells. Here, we report that myeloid cell infiltration was enhanced and FRß was upregulated at distinct stages of tumorigenesis in a mouse breast cancer model. The CD206+ subset of macrophages highly expressed FRß, prominently both in tumor-bearing and healthy mice. In tumor-bearing mice, the amount of all myeloid cells, but particularly granulocytes, was remarkably increased in the tumor, liver, lungs, spleen, kidneys, lymph nodes, peritoneal cavity, bone marrow, heart, and brain. Compared with macrophages, the level of FRß was moderate in granulocytes and monocytes. The density of FRß+ immune cells in the tumor microenvironment was not directly associated with the tumor-targeting efficacy of the folate-functionalized cyclodextrin nanoparticles. The lung was determined as a preferential site of accumulation for folate-functionalized nanoparticles, wherein FRß+CD206+ macrophages significantly engulfed cyclodextrin nanoparticles. In conclusion, our results demonstrate that the tumor formation augments the FR levels and alters the infiltration and distribution of myeloid immune cells in all organs which should be considered as a major factor influencing the targeting efficacy of nanoparticles for drug delivery.

14.
Microb Cell Fact ; 23(1): 130, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711033

RESUMO

BACKGROUND: Cyclic ß-1,2-glucans (CßG) are bacterial cyclic homopolysaccharides with interesting biotechnological applications. These ring-shaped molecules have a hydrophilic surface that confers high solubility and a hydrophobic cavity able to include poorly soluble molecules. Several studies demonstrate that CßG and many derivatives can be applied in drug solubilization and stabilization, enantiomer separation, catalysis, synthesis of nanomaterials and even as immunomodulators, suggesting these molecules have great potential for their industrial and commercial exploitation. Nowadays, there is no method to produce CßG by chemical synthesis and bacteria that synthesize them are slow-growing or even pathogenic, which makes the scaling up of the process difficult and expensive. Therefore, scalable production and purification methods are needed to afford the demand and expand the repertoire of applications of CßG. RESULTS: We present the production of CßG in specially designed E. coli strains by means of the deletion of intrinsic polysaccharide biosynthetic genes and the heterologous expression of enzymes involved in CßG synthesis, transport and succinilation. These strains produce different types of CßG: unsubstituted CßG, anionic CßG and CßG of high size. Unsubstituted CßG with a degree of polymerization of 17 to 24 glucoses were produced and secreted to the culture medium by one of the strains. Through high cell density culture (HCDC) of that strain we were able to produce 4,5 g of pure unsubstituted CßG /L in culture medium within 48 h culture. CONCLUSIONS: We have developed a new recombinant bacterial system for the synthesis of cyclic ß-1,2-glucans, expanding the use of bacteria as a platform for the production of new polysaccharides with biotechnological applications. This new approach allowed us to produce CßG in E. coli with high yields and the highest volumetric productivity reported to date. We expect this new highly scalable system facilitates CßG availability for further research and the widespread use of these promising molecules across many application fields.


Assuntos
Escherichia coli , beta-Glucanas , Escherichia coli/metabolismo , Escherichia coli/genética , beta-Glucanas/metabolismo
15.
Microb Cell Fact ; 23(1): 30, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245746

RESUMO

BACKGROUND: The global prevalence of vitamin D (VitD) deficiency associated with numerous acute and chronic diseases has led to strategies to improve the VitD status through dietary intake of VitD-fortified foods and VitD supplementation. In this context, the circulating form of VitD3 (cholecalciferol) in the human body, 25-hydroxy-VitD3 (calcifediol, 25OHVitD3), has a much higher efficacy in improving the VitD status, which has motivated researchers to develop methods for its effective and sustainable synthesis. Conventional monooxygenase-/peroxygenase-based biocatalytic platforms for the conversion of VitD3 to value-added 25OHVitD3 are generally limited by a low selectivity and yield, costly reliance on cyclodextrins and electron donor systems, or by the use of toxic co-substrates. RESULTS: In this study, we used a whole-cell approach for biocatalytic 25OHVitD3 synthesis, in which a molybdenum-dependent steroid C25 dehydrogenase was produced in the denitrifying bacterium Thauera aromatica under semi-aerobic conditions, where the activity of the enzyme remained stable. This enzyme uses water as a highly selective VitD3 hydroxylating agent and is independent of an electron donor system. High density suspensions of resting cells producing steroid C25 dehydrogenase catalysed the conversion of VitD3 to 25OHVitD3 using either O2 via the endogenous respiratory chain or externally added ferricyanide as low cost electron acceptor. The maximum 25OHVitD3 titer achieved was 1.85 g L-1 within 50 h with a yield of 99%, which is 2.2 times higher than the highest reported value obtained with previous biocatalytic systems. In addition, we developed a simple method for the recycling of the costly VitD3 solubiliser cyclodextrin, which could be reused for 10 reaction cycles without a significant loss of quality or quantity. CONCLUSIONS: The established steroid C25 dehydrogenase-based whole-cell system for the value-adding conversion of VitD3 to 25OHVitD3 offers a number of advantages in comparison to conventional oxygenase-/peroxygenase-based systems including its high selectivity, independence from an electron donor system, and the higher product titer and yield. Together with the established cyclodextrin recycling procedure, the established system provides an attractive platform for large-scale 25OHVitD3 synthesis.


Assuntos
Ciclodextrinas , Deficiência de Vitamina D , Vitamina D/análogos & derivados , Humanos , Calcifediol , Molibdênio , Colecalciferol , Vitaminas , Esteroides
16.
Nanotechnology ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39146959

RESUMO

ß-Cyclodextrin (ß-CD) -functionalized carbon quantum dots (CDs) loaded with curcumin (CCM) were used for ClO--sensing with high sensitivity and selectivity. This fluorescence resonance energy transfer (FRET)-based sensor was created through attaching CCM to the CDs via ß-CD linker. CCM could get into the interior of ß-CD triggering the FRET from CDs to CCM, providing an "off" state of the CDs. However, the effect of FRET was weakened by the ClO-, because the o- methoxyphenol structure from CCM was oxidized to be benzoquinone. The fluorescence intensity of CDs@ß-CD@CCM at 440 nm can be heightened and 520 nm from CCM can decrease along with the increased ClO-. Therefore, a ratiometric fluorescence probe for ClO--sensing is successfully constructed. It conforms to a polynomial curve equation which is I440/I520 = -0.0268+0.0315 CClO-+0.0055[CClO-]2 (R2= 0.9958) between 0-18.4 µM ClO-. Furthermore, we also obtain excellent results using this spectrophotometric method for ClO-- sensing in pure water and commercial disinfectants, which afford potential in the environment monitoring area. We expect this sensing platform could be helpful in other analogous probes in relevant fields.

17.
Nanotechnology ; 35(28)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38522104

RESUMO

Surface enhanced Raman spectroscopy (SERS) is a powerful analytical technique that has found application in the trace detection of a wide range of contaminants. In this paper, we report on the fabrication of 2D silver nanodendrites, on silicon chips, synthesized by electrochemical reduction of AgNO3at microelectrodes. The formation of nanodendrites is tentatively explained in terms of electromigration and diffusion of silver ions. Electrochemical characterization suggests that the nanodendrites do not stay electrically connected to the microelectrode. The substrates show SERS activity with an enhancement factor on the order of 106. Density functional theory simulations were carried out to investigate the suitability of the fabricated substrate for pesticide monitoring. These substrates can be functionalized with cyclodextrin macro molecules to help with the detection of molecules with low affinity with silver surfaces. A proof of concept is demonstrated with the detection of the herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA).

18.
J Fluoresc ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060827

RESUMO

In this paper the binding of noscapine (NOS) as an anticancer drug with poor bioavailability and low solubility with beta and methyl-beta cyclodextrins (ß-CD and M-ß-CD) as the biocompatible drug carriers were discussed using ultraviolet-visible, fluorescence and nuclear magnetic resonance spectroscopy, as well as molecular docking. The absorption of NOS changed when it was bound to both cyclodextrins, resulting in a hyperchromic shift. It formed a 1:1 stoichiometry inclusion complex with both cyclodextrins according to the Benesi-Hildebrand equation. The binding affinity was larger in NOS-M-ß-CD (5.9 (± 0.66) × 103 M- 1) than NOS-ß-CD (3.7 (± 0.22) × 103 M- 1) complex. The fluorescence emission band of NOS at 408 nm was quenched when NOS was complexed with ß-CD, and enhanced in the presence of M-ß-CD, while the shoulder at 350 nm was enhanced selectively when NOS was complexed with M-ß-CD. The fluorescence quenching of NOS with ß-CD showed a negative deviation from the Stern-Volmer. The thermodynamic parameters have been estimated with the help of the Van't Hoff equation in different temperatures, and a dynamic mechanism was proposed for quenching. Also, both ΔH and ΔS have positive values thus the main interactions result in hydrophobic forces. Moreover, the negative value of ΔG indicates that the bonding process is spontaneous. 1H NMR chemical shift changes were observable for NOS and both CDs protons due to the chemical environment changes of some nuclei upon complexation. The molecular docking results revealed that the 1:1 inclusion complex possesses a good molecular shape complementarity score for their most probable structures, and indicated that the M-ß-CD inclusion system gave the higher complexation efficiency. The binding energy values for ß-CD and M-ß-CD were determined to be -6.7 and - 9.5 kcal/mol, respectively. These findings suggest the same as the result of experimental tests that the NOS-M-ß-CD complex is more stable than the NOS-ß-CD complex.

19.
Environ Res ; 258: 119472, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38908665

RESUMO

The study investigated the influence of additives on the fabrication of mixed matrix membranes comprising polyethersulfone (PES), with a specific focus on hydrophilicity, flux, morphology, and antifouling properties. Carboxymethyl modified ß-cyclodextrin (CMß-CD) was used to enhance the dispersion and hydrophilicity of graphene oxide (GO), leading to the formation of a hydrophilic and stable composite nanoparticle (CMCD@GO). The hydrophilicity (WCA <51.5°) and water flux (32.6 L m-2.h-1) of the modified PES membranes (MCDGO-x) were improved by the incorporation of CMCD@GO nanoparticles, while that of PES membrane was 79.7° and 10.6 L m-2.h-1. The rate of backscattered light intensity (ΔBS) of MCDGO-x suspensions remains stable, suggesting stable dispersion of CMCD@GO in organic solvents. Compared to the bare PES membrane, the MCDGO-x membrane exhibits a thinner active layer and a finger-like structure. The MCDGO-x membrane exhibited excellent naphthenic acids (NAs) rejection (>93.2%) due to reduced roughness and higher hydrophilicity, while the GO-modified PES membrane (MGO-5) exhibited lower NAs rejection (87.2%). Furthermore, the MCDGO-5 membrane showed higher flux recovery ratio (FRR) of 79.3% compared to MGO-5 membrane (68.5%) after three cycles, indicating the antifouling performance of MCDGO-x for NAs was significantly improved. The combination of CMß-CD and GO enhance the flux and antifouling properties of PES ultrafiltration membranes, suggesting significant potential for applications in the purification of oil sands process water and the treatment of oily wastewater.


Assuntos
Incrustação Biológica , Grafite , Membranas Artificiais , Ultrafiltração , Purificação da Água , beta-Ciclodextrinas , beta-Ciclodextrinas/química , Grafite/química , Purificação da Água/métodos , Ultrafiltração/métodos , Incrustação Biológica/prevenção & controle , Interações Hidrofóbicas e Hidrofílicas , Sulfonas/química , Polímeros
20.
Appl Microbiol Biotechnol ; 108(1): 100, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38217256

RESUMO

Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate (ODHP) was extracted in a previous study from the culture broth of soil isolate Alcaligenes faecalis MT332429 and showed a promising antimycotic activity. This study was aimed to formulate ODHP loaded ß-cyclodextrins (CD) nanosponge (NS) hydrogel (HG) to control skin fungal ailments since nanosponges augment the retention of tested agents in the skin. Box-Behnken design was used to produce the optimized NS formulation, where entrapment efficiency percent (EE%), polydispersity index (PDI), and particle size (PS) were assigned as dependent parameters, while the independent process parameters were polyvinyl alcohol % (w/v %), polymer-linker ratio, homogenization time, and speed. The carbopol 940 hydrogel was then created by incorporating the nanosponges. The hydrogel fit Higuchi's kinetic release model the best, according to in vitro drug release. Stability and photodegradation studies revealed that the NS-HG remained stable under tested conditions. The formulation also showed higher in vitro antifungal activity against Candida albicans compared to the control fluconazole. In vivo study showed that ODHP-NS-HG increased survival rates, wound contraction, and healing of wound gap and inhibited the inflammation process compared to the other control groups. The histopathological examinations and Masson's trichrome staining showed improved healing and higher records of collagen deposition. Moreover, the permeability of ODHP-NS-HG was higher through rats' skin by 1.5-folds compared to the control isoconazole 1%. Therefore, based on these results, NS-HG formulation is a potential carrier for enhanced and improved topical delivery of ODHP. Our study is a pioneering research on the development of a formulation for ODHP produced naturally from soil bacteria. KEY POINTS: • Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propanoate was successfully formulated as a nanosponge hydrogel and statistically optimized. • The new formula exhibited in vitro good stability, drug release, and higher antifungal activity against C. albicans as compared to the fluconazole. • Ex vivo showed enhanced skin permeability, and in vivo analysis showed high antifungal activity as evidenced by measurement of various biochemical parameters and histopathological examination.


Assuntos
Alcaligenes faecalis , Butanos , Hidrogéis , Ratos , Animais , Antifúngicos/farmacologia , Fluconazol , Propionatos , Candida albicans , Solo , Tamanho da Partícula
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