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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124965, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39153345

RESUMO

AFB1 is a harmful substance that can be found in agricultural products and can seriously affect human health, even in trace amounts. Therefore, monitoring AFB1 levels to ensure food safety and protect public health is crucial. New, highly reliable, selective, and rapid detection methods are needed to achieve this goal. Our work involves the development of a polymeric membrane sensor using radical polymerization that can accurately detect AFB1. Various spectroscopic techniques (Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM)) were used to obtain information about the structural and morphological properties of the prepared sensor. The sensor displayed fluorescence selectively responsive to AFB1 at the excitation wavelength of 376 nm and emission wavelength of 423 nm. The polymeric fluorescence sensor showed good sensitivity and a wide linear range from 9.61 × 10-10 and 9.61 × 10-9 mol/L for AFB1quantification. The limit of detection (LOD) is as low as 3.84 × 10-10 mol/L for AFB1. Other mycotoxins, such as aflatoxin B2 and aflatoxin G1, did not interfere with the sensor's high selectivity towards AFB1. To test the sensor's effectiveness in detecting AFB1 in real samples, three different grain samples - peanuts, hazelnut butter, and peanuts with a sauce known to contain AFB1 - were utilized. The results were satisfactory and demonstrated that the sensor can be successfully employed in real samples, with an error range of 0.43 % to 12.10 %.


Assuntos
Aflatoxina B1 , Limite de Detecção , Espectrometria de Fluorescência , beta-Ciclodextrinas , Aflatoxina B1/análise , Espectrometria de Fluorescência/métodos , beta-Ciclodextrinas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Contaminação de Alimentos/análise , Grão Comestível/química , Polímeros/química
2.
Angew Chem Int Ed Engl ; : e202413901, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221519

RESUMO

The development of a mechanochemical Fe-catalyzed Wacker oxidation of olefins with a sustainable and benign procedure holds significant promise for industrial applications. However, navigating the intricate interactions inherent in ball-milling conditions to fine-tune reaction selectivity remains a formidable challenge. Herein, leveraging the dispersive and/or trapping properties of cyclodextrins, an innovative mechanochemical approach is developed through the integration of cyclodextrins into a Fe-catalyzed system, enabling a streamlined Wacker oxidation process from simple and/or commercially available alkenes. Our efforts have yielded optimized mechanochemical conditions demonstrating exceptional reactivity and selectivity in generating a diverse array of ketone products, markedly enhancing catalytic efficiency compared to conventional batch methods. Mechanistic investigations have revealed a predominantly Markovnikov-selective catalytic cycle, effectively minimizing undesired alcohol formation, hydrogenation, and the other competing pathways, boosting both reaction yield and selectivity.

3.
Anal Bioanal Chem ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39230749

RESUMO

CD-MONs (ß-cyclodextrin-based microporous organic networks), derived from ß-cyclodextrin, possess notable hydrophobic characteristics, a considerable specific surface area, and remarkable stability, rendering them highly advantageous in separation science. This research aimed to investigate the utility of CD-MONs in chromatography separation. Through a monomer-mediated technique, we fabricated an innovative CD-MON modified capillary column for application in open-tubular capillary electrochromatography (OT-CEC). The CD-MON-based stationary phase on the capillary's inner surface was analyzed using Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). We assessed the performance of the CD-MON modified capillary column for separation purposes. The microstructure and pronounced hydrophobicity of CD-MON contributed to enhanced selectivity and resolution in separating diverse hydrophobic analytes, such as alkylbenzenes, halogenated benzenes, parabens, and polycyclic aromatic hydrocarbons (PAHs). The maximum column efficiency achieved was 1.5 × 105 N/m. Additionally, the CD-MON modified capillary column demonstrated notably high column capacity, with a methylbenzene mass loading capacity of up to 197.9 pmol, surpassing that of previously reported porous-material-based capillaries. Furthermore, this self-constructed column was effectively utilized for PAHs determination in actual environmental water samples, exhibiting spiked recoveries ranging from 93.2 to 107.9% in lake water samples. These findings underscore the potential of CD-MON as an effective stationary phase in separation science.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39259880

RESUMO

Conductive hydrogels exhibit tremendous potential for wearable bioelectronics, biosensing, and health monitoring applications, yet concurrently enhancing their biocompatibility and antimicrobial properties remains a long-standing challenge. Herein, we report an all-natural conductive supramolecular hydrogel (GT5-DACD2-B) prepared via the Schiff base reaction between the biofriendly dialdehyde cyclodextrin and gelatin. The potent antibacterial agent fusidic acid (FA) is incorporated through host-guest inclusion, enabling 100% inhibition of Staphylococcus aureus proliferation. The biocompatibility of our hydrogel is bolstered with tannic acid (TA) facilitating antibacterial effects through interactions with gelatin, while borax augments conductivity. This supramolecular hydrogel not only exhibits stable conductivity and rapid response characteristics but also functions as a flexible sensor for monitoring human movement, facial expressions, and speech recognition. Innovatively integrating biocompatibility, antimicrobial activity, and conductivity into a single system, our work pioneers a paradigm for developing multifunctional biosensors with integrated antibacterial functionalities, paving the way for advanced wearable bioelectronics with enhanced safety and multifunctionality.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39259941

RESUMO

Modern drug delivery research focuses on developing biodegradable nanopolymer systems. The present study proposed a polymer-based composite nanogel as a transdermal drug delivery system for the pH-responsive targeted and controlled delivery of anticancer drug doxorubicin (DOX). Nanogels have properties of both hydrogels and nanomaterials. The ß-cyclodextrin-based nanogels can enhance the loading capacity of poorly soluble drugs and promote a sustained drug release. The ß-cyclodextrin-grafted methacrylic acid conjugated hyaluronic acid composite nanogel was successfully synthesized. ß-Cyclodextrin was first grafted onto methacrylic acid. The composite nanogel-based drug carrier was prepared by controlled radical polymerization (CRP) of ß-cyclodextrin-grafted methacrylic acid with hyaluronic acid. The doxorubicin-loaded carrier was characterized by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, zeta potential analysis, dynamic light scattering (DLS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The drug loading and release efficiencies were carried out at different pH levels. The maximum drug loading and encapsulation efficiencies of the synthesized final nanogel composite material at pH 8.0 were 86.44 ± 2.12 and 96.07 ± 2.01%, respectively. The DOX-loaded final material showed a 90.0 ± 2.6% release percentage of DOX at pH 5.5, whereas at pH 7.4, the release percentage of DOX was observed to be only 35.0 ± 0.3%. In vitro swelling, degradation, hemocompatibility, drug release kinetics, cytotoxicity, apoptosis, cell colocalization, skin irritation, and skin permeation studies, along with in vivo pharmacokinetic studies, were performed to prove the efficacy of the synthesized nanogel composite as a transdermal carrier for doxorubicin.

6.
Carbohydr Polym ; 346: 122483, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39245475

RESUMO

A computational study was performed to unravel mechanisms underlying capillary electrophoresis enantioseparations of daclatasvir and its (R,R,R,R)-enantiomer with native and methylated ß-cyclodextrins (ß-CDs) as chiral selectors. Considering the enantioseparation results as benchmark, the structures of ß-CD and seven methylated ß-CDs were optimized by quantum mechanics, and their topography and computed molecular properties were compared. Furthermore, the electron charge density distribution of the macrocycles was also evaluated by calculating the molecular electrostatic potential of pivotal regions of native and methylated ß-CDs. The function of hydrogen bonds in the complexation process of daclatasvir and the CDs was derived from quantum mechanics analysis and confirmed by molecular dynamics, as orthogonal computational techniques. The presence of a round-shaped cavity in the CDs used as chiral selector appeared as a necessary requirement for the enantioseparation of daclatasvir and its (R,R,R,R)-enantiomer. In this regard, it was confirmed that the round shape of the CDs is sustained by hydrogen bonds formed between adjacent glucopyranose units and blocking rotation of the linking glycosidic bonds. The presence of hydroxy groups at the 6-position of the glucopyranose units and the concurrent absence of hydroxy groups at the 2-position were evidenced as important factors for enantioseparation of daclatasvir and its enantiomer by methylated ß-CDs.

7.
ChemMedChem ; : e202400368, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39246269

RESUMO

Cyclodextrin dimers have been investigated as potential nanocapsules of biomolecules. The presence of two cavities can improve the stability of inclusion complexes, working as a hydrophilic sandwich of poorly water-soluble species. Here, we designed new ß- and γ-cyclodextrin dimers functionalized with biotin as a targeting unit and tested the new bioconjugates as doxorubicin delivery systems in cancer cells. Biotin can recognize the Sodium-dependent Multivitamin Transporter (SMVT) receptor, encoded by the Solute Carrier Family 5 Member 6 (SLC5A6) gene and improve the uptake of drugs. We evaluated the expression of the SLC5A6 transcript in human cell lines to select the best cell model (MCF-7) for the in vitro studies. Furthermore, in the cell lines, we investigated the transcript levels of genes correlated to biotin cell availability, Holocarboxylase Synthetase (or HCS encoded by HLCS gene) and Biotinidase (encoded by BTD gene) enzymes. Moreover, the expression of ATP Binding Cassette Subfamily G Member 2 transporter (encoded by ABCG2 gene), which may play a role in doxorubicin resistance, has been investigated. The antiproliferative activity of the doxorubicin complexes with the dimers has been determined to study the effect of the biotin moiety on the cytotoxicity in MCF-7 cancer cells.

8.
Carbohydr Polym ; 345: 122563, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39227102

RESUMO

γ-Cyclodextrin (γ-CD) is an attractive material among the natural cyclodextrins owing to its excellent properties. γ-CD is primarily produced from starch by γ-cyclodextrin glycosyltransferase (γ-CGTase) in a controlled system. However, difficulty in separation and low conversion rate leads to high production costs for γ-CD. In this study, γ-CGTase from Bacillus sp. G-825-6 STB17 was used in γ-CD production from cassava starch. With the introduction of sodium tetraphenylborate (NaBPh4), the total conversion rate was promoted from an initial 18.07 % to 50.49 % and the γ-CD ratio reached 78.81 % with a yield of 39.79 g/L. Furthermore, the mechanism was conducted via the determination of binding constant, which indicated that γ-CD exhibited much stronger binding strength with NaBPh4 than ß-CD. The reformation of water molecules and the chaotropic effect might be the main driving forces for the interaction. Additionally, the conformations of CD complexes were depicted by NMR and molecular docking. The results further verified different binding patterns between CDs and tetraphenylborate ions, which might be the primary reason for the specific binding. This system not only guides γ-CD production with an efficient and easy-to-remove production aid but also offers a new perspective on the selection of complexing agents in CD production.


Assuntos
Bacillus , Boratos , Glucosiltransferases , Simulação de Acoplamento Molecular , gama-Ciclodextrinas , gama-Ciclodextrinas/química , gama-Ciclodextrinas/metabolismo , Bacillus/enzimologia , Boratos/química , Glucosiltransferases/metabolismo , Glucosiltransferases/química , Amido/química , Amido/metabolismo , Manihot/química
9.
Chempluschem ; : e202400475, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248048

RESUMO

Desolvation processes, though common in self-assembled biological structures, are rarely evidenced and utilized in the design of crystalline architectures. In this study, we introduce a novel approach using the [Mo8S8O8(OH)8(guest)]2- complex, formed by the self-condensation of four [MoV2O2S2]2- fragments around a guest unit (MoVIO6H4 or oxalate), as a chaotropic scaffold for crystallizing hybrid organic-inorganic systems with natural cyclodextrins. Our findings reveal that ß-cyclodextrin (ß-CD) facilitates the formation of host-guest complexes, while α-cyclodextrin (α-CD) induces the formation of a Kagome-type structure with significant voids. These new compounds were thoroughly characterized using X-ray diffraction (both powder and single-crystal), N2 adsorption, elemental and thermogravimetric analysis. Additionally, solution studies using 1H NMR titration and small-angle X-ray scattering (SAXS) demonstrated pre-association of the building units in solution. These results enhance our understanding of the design principles for supramolecular structures composed of inorganic polyanions and cyclodextrins.

10.
Int J Biol Macromol ; : 135194, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39256120

RESUMO

The antimicrobial and pro-healing properties remain critical clinical objectives for skin wound management. However, the escalating problem of antibiotic overuse and the corresponding rise in bacterial resistance necessitates an urgent shift towards an antibiotic-free approach to antibacterial treatment. The quest for antimicrobial efficacy while accelerating wound healing without antibiotic treatment have emerged as innovative strategies in skin wound treatment. Here, a dual-function hydrogel with antimicrobial and enhanced tissue-healing properties was developed by utilizing cyclodextrin, ferrocene, polyethyleneimine (PEI), and Bletilla striata polysaccharide (BSP), through multiple non-covalent interactions, which can intelligently release BSP by recognizing the wound inflammatory microenvironment through the cyclodextrin-ferrocene unit. Moreover, the porosity (65 % - 85 %), Young's modulus (400 KPa - 140 KPa), and DPPH scavenge rate (18 % - 40 %) of the hydrogel are modulated by varying the BSP content. The hydrogel exhibits outstanding antibacterial properties (98.3 % reduction of Escherichia coli observed after exposure to HTFC@BSP-20 for 24 h) and favorable biocompatibility. Furthermore, in a rat full-thickness skin wound model, the dual-function hydrogel significantly accelerates wound healing, increased CD31 expression promotes vascular regeneration, reduced TNF-α express and inhibited the inflammation. This multifunctional ROS responsive hydrogel provides a new perspective for antibiotics-free treatment of skin injuries.

11.
Sci Rep ; 14(1): 20676, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237578

RESUMO

In these decades, considerable attention has focused on supramolecular polymers due to their unique structures and properties. More recently, macroscopic supramolecular polymers have attracted increasing interest from not only biologists but also materials scientists inspired by the sophisticated structures and functions of living organisms. Since the functions of supramolecular polymers are strongly dependent on their shape, control of the shape is an important issue in controlling the functions of supramolecular polymers. However, the control of shape in macroscopic supramolecular assemblies has not yet been sufficiently investigated. Previously, we studied the macroscopic self-assembly behavior of super absorbent polymer (SAP) microparticles modified with ß-cyclodextrin (ßCD) and adamantane (Ad) residues (ßCD(x)-SAP and Ad(y)-SAP microparticles, where x and y are the mol% contents of ßCD and Ad residues, respectively). More elongated assemblies were formed at higher y, indicating that the shape of assemblies can be controlled by varying the interaction strength. The noteworthy is that 1-adamantanamine hydrochloride (AdNH3Cl) assisted the formation of assemblies from ßCD(x)-SAP and Ad(y)-SAP microparticles, indicating that AdNH3Cl acts as a chemical stimulus for macroscopic assemblies of ßCD(x)-SAP and Ad(y)-SAP microparticles. In this study, we have thus studied the assembling behavior of ßCD(x)-SAP microparticles with Ad(y)-SAP microparticles and unmodified SAP microparticles assisted by AdNH3Cl, as well as the shape of the resulting macroscopic assemblies. AdNH3Cl assisted the formation of assemblies from ßCD(16.2)-SAP and Ad(15.1)-SAP microparticles, in which AdNH3Cl crosslinked the SAP microparticles through the formation of inclusion complexes of ßCD residues with the Ad residue and the electrostatic interaction of ammonium and carboxylate residues. Assemblies of ßCD(26.7)-SAP and unmodified SAP microparticles were formed at the concentrations of AdNH3Cl ([AdNH3Cl]0) higher than a certain level (ca. 0.05 mM). The aspect ratio (a/b) of assemblies showed a maximum at [AdNH3Cl]0 ~ 0.10 mM, indicating that the chemical stimulus, i.e., addition of AdNH3Cl, controls the shape of assemblies formed from ßCD(26.7)-SAP and unmodified SAP microparticles. This study suggests that other stimuli, e.g., heat, pH, light, redox, and force, can be utilized to control the shape of macroscopic assemblies based on supramolecular interactions.

12.
Ther Deliv ; : 1-14, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225262

RESUMO

Aim: In this study, we aimed to prepare enteric encapsulated spheroids containing inclusion complex using quality by design approach. Methods: A Box-Behnken design was employed to determine effects of variables on selected responses. Risk assessment was conducted using Ishikawa fishbone diagram. A model with a p-value was less than 0.5 for being a significant error of model was determined based on significance 'lack of fit' value. Spheroids were formulated using the extrusion spheronization technique and were characterized using analytical techniques. Results: In vitro release was performed in both acidic (pH 1.2) and simulated intestinal (pH 6.8) conditions. Permeability studies demonstrated tenfold enhancement compared with arteether. In vivo studies further validated increase of 51.8% oral bioavailability. Ex vivo studies revealed 3.4-fold enhancement in antimalarial activity compared with arteether. Conclusion: These findings highlight effectiveness of inclusion complexation technique as a viable approach to enhance solubility and bioavailability for drugs with low aqueous solubility.


[Box: see text].

13.
Colloids Surf B Biointerfaces ; 245: 114200, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39236360

RESUMO

A water stable cyclodextrin MOF (Cu-SD) was synthesized with γ-cyclodextrin derivative as organic ligand and Cu2+ as metal center to co-crystallizely load glycyrrhizic acid (GL) and glycyrrhetinic acid (GA). Cu-SD has a high drug loading capacity for GL (499.91 µg/mg) and GA (112.37 µg/mg), and the drug-loaded materials had a controlled release in different meadiums. In addition, Cu-SD and its drug loaded materials demonstrated better inhibiting α-glucosidase activity than the control drug acarbose. Furthermore, Cu-SD presented excellent antibacterial activity, and the antibacterial activity was significantly enhanced after GA and GL being encapsulated by Cu-SD. Moreover, both free and drug-loaded materials had good anti-inflammatory activities, and the anti-inflammatory effects of GL@Cu-SD and GA@Cu-SD were superior to those of their corresponding free drugs. Cu-SD, GL@Cu-SD and GA@Cu-SD demonstrated good biocompatibility and were applied to treat the wounds of diabetic rats. The experimental results showed that GL@Cu-SD and GA@Cu-SD had good promoting effects on the recovery of chronic diabetic wounds by suppressing wound inflammation.

14.
Anal Chim Acta ; 1328: 343182, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39266198

RESUMO

BACKGROUND: Chemiluminescence (CL) bioassay is one of the most advanced and used detection method in clinical diagnosis and biomedical research because of the advantages of low background, easy operation, and wide-field imaging without a light source or microscope. The luminol/hydrogen peroxide/horseradish peroxidase (luminol/H2O2/HRP) system is the most popular CL system, but its application in high-throughput imaging detection is challenged due to its low luminescence efficiency and flash-type emission which is difficult in ensuring the reproducibility and consistency of detection results. RESULTS: We reported a glow-type CL system of luminol@CD/H2O2/HRP by using a supramolecular enhancer of cyclodextrin (CD). This luminol@CD/H2O2/HRP system exhibited a luminescence lifetime of 41 min for sensitive and accurate imaging analysis. The long-lasting CL emission was attributed to the formation of a 1:1 host-guest complex between luminol and CD, which could stabilize the emitter and effectively reduce nonradiative relaxation. The formation of luminol@CD complex was determined through NMR experiments and theoretical analysis. Under optimum conditions, the luminol@CD/H2O2/HRP system showed higher sensitivity and much better precision than classical luminol/H2O2/HRP system for imaging detection of HRP. Especially, this glow-type luminol@CD/H2O2/HRP system realized CL imaging of microwell arrays on microfluidic chips. In addition, the luminol@CD/H2O2/HRP system was successfully applied for point-of-care detection of 17ß-estradiol based on a competitive mechanism of host-guest recognition. SIGNIFICANCE: An efficient CL system is crucial for obtaining reproducible and consistent results for accurate detection. Our luminol@CD/H2O2/HRP system emitted strong and persistent luminescence, resulting in reliability and efficiency at both CL macroscopic and microscopic imaging detection. We expected the luminol@CD/H2O2/HRP CL system to be applied in various detection fields.


Assuntos
Ciclodextrinas , Peroxidase do Rábano Silvestre , Peróxido de Hidrogênio , Medições Luminescentes , Luminol , Luminol/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Ciclodextrinas/química , Medições Luminescentes/métodos , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Luminescência , Limite de Detecção
15.
Int J Biol Macromol ; 279(Pt 3): 135379, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39244122

RESUMO

The synergistic effects between xanthan gum (XG) and ß-cyclodextrin (ß-CD) on the properties and stability of vegetable oil-based whipped cream stabilized by kidney bean protein aggregates was investigated. The visual appearance, SEM, TEM, CLSM, FT-IR and LF-NMR results showed that when the ratio of XG to ß-CD in the XG-ß-CD complex was appropriate, the hydrogen bonding effect between ß-CD and XG was significant enhanced, the three-dimensional network structure has the highest density, the emulsion droplets were the smallest and evenly distributed. The unique tapered microstructure of ß-CD acted as a bridge between the hydrophilic and hydrophobic components, effectively preventing the aggregation of oil droplets and establishing a flexible support system between oil droplets; while the flexible molecular structure of XG could support Pickering emulsion system. The XG-ß-CD complex had a synergistic effect with protein aggregates, making it ideal for use in whipped cream products. This study explored the stability mechanism of ß-CD in the Pickering emulsion-based whipped cream system, providing valuable insights into producing whole plant-based whipped cream by texturizing highly unsaturated oils. This effectively solves the problem of inadequate intake of unsaturated oil for individuals who consume excessive amounts of animal-derived fats.

16.
Carbohydr Polym ; 343: 122437, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39174082

RESUMO

Bisphenol A (BPA), a prominent endocrine-disrupting compound, has garnered considerable attention due to its urgent need for rapid removal from water. Herein, we first used a novel reactive phosphine oxide containing tertiary amines as crosslinker to prepare water-insoluble crosslinked ß-cyclodextrin (ß-CD) adsorbent via radical-mediated thiol-ene polymerization. Owing to the synergistic hydrogen-bond (H-bond) interactions of functional groups (tertiary amine and PO groups) toward BPA, the resulted adsorbents showed fast adsorption kinetics to BPA with an adsorption equilibrium time of 5 min. After six adsorption-desorption cycles, the removal efficiency of BPA was 92.5 %, indicating its excellent reusability. Due to the presence of the CS bonds, the ß-CD -derived bio-adsorbents offered binding sites for Cu2+ ions, resulting in a maximum adsorption capacity of 113.89 mg g-1.

17.
Carbohydr Polym ; 343: 122446, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39174087

RESUMO

The spontaneous formation of cyclodextrin (CD)-oil inclusion complexes (ICs) and their further growth into patterned crystals present a bottom-up route to the fabrication of periodic macroscopic structure. Although the inclusion processes are well established for the molecules, understanding intermediate structures during the crystal growth and emerging of persistent crystalline order has been lacking. Here we build a hierarchy of oriented micro/nanostructures of CD-oil ICs in solution by choosing different oil guests including several straight-chain alkanes of C12, C14 and C16, oleic acid (OA), glycerol trioleate (TG) and soybean oil (SO), in an attempt to reveal the roles of oil guests in the formation of their crystallites. Remarkably, the ICs tend to grow into clusters and terminate at a certain finite size as long columns or lamella plates with well-defined facets, dependent on the type of oil used. For the first time, we report a non-equilibrium growth of crystallites with surface faceting directed by the guests by means of Arching and Bundling.

18.
Carbohydr Polym ; 343: 122454, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39174132

RESUMO

Efficient, green and stable catalysis has always been the core concept of enzyme catalysis in industrial processes for manufacturing. Therefore, we construct a new strategy with photothermal interfacial molecular transfer for green and efficient biodiesel catalysis. We encapsulate Candida albicans lipase B (CalB) in a γ-cyclodextrin metal-organic framework (γ-CD-MOF) loading with Ti3C2TX by in situ growth and electrostatic assembly. The γ-CD-MOF not only protects the fragile enzyme, but also enhances the catalytic performance through the synergistic effects of porous adsorption (MOF pore structure) and interfacial enrichment (cyclodextrins host-guest assembly structure) for accelerating substrate transfer (642.6 %). The CalB@γ-CD-MOF/MXene-i activity can be regulated up to 274.6 % by exposure to near-infrared (NIR). Importantly, CalB@γ-CD-MOF/MXene-i achieves 93.3 % biodiesel conversion under NIR and maintained 86.9 % activity after 6 cycles. Meanwhile, the MXene after the CalB@γ-CD-MOF/MXene catalytic cycle can be almost completely recovered. We verify the mechanism of high catalytic activity of γ-CD-MOF and rationalize the mechanism of CD molecular channel by DFT. Therefore, this highly selective enzyme catalytic platform offers new possibilities for green and efficient preparation of bioenergy.


Assuntos
Biocombustíveis , Proteínas Fúngicas , Lipase , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Lipase/química , Lipase/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Candida albicans/enzimologia , Biocatálise , gama-Ciclodextrinas/química , Catálise , Porosidade , Titânio/química
19.
Eur J Pharm Sci ; 202: 106879, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39154714

RESUMO

Nasal systemic drug delivery may provide an easy way to substitute parenteral or oral dosing, however, the excipients have an important role in nasal formulations to increase the permeability of the mucosa and prolong the residence time of the drug. In this work, we aimed to produce meloxicam potassium monohydrate (MXP) containing nasal powders by a nano spray drier with the use of a neutral, an anionic and a cationic ß-cyclodextrin as permeation enhancers, and (polyvinyl)alcohol (PVA) as a water soluble polymer. The following examinations were performed in order to study the effect of the applied excipients on the nasal applicability of the formulations: laser scattering, scanning electron microscope measurement, XRPD, DSC and FTIR measurements, adhesivity, in vitro drug release and permeability tests through an artificial membrane and RPMI 2650 cells. Based on our results, spherical particles were prepared with a size of 1.89-2.21 µm in which MXP was present in an amorphous state. Secondary interactions were formed between the excipients and the drug. The charged cyclodextrin-based formulations showed significantly higher adhesive force values regardless of the presence of PVA. The drug release was fast and complete. The passive diffusion of MXP was influenced not only by the charge of the cyclodextrin, but the presence of PVA, too. The permeation of the drug was enhanced in the presence of the anionic cyclodextrin testing it on RPMI 2650 cell model.

20.
Int J Biol Macromol ; 278(Pt 3): 134819, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39154672

RESUMO

Treatment of multiple bacterial infected wounds by eliminating bacteria and promoting tissue regeneration remains a clinical challenge. Herein, dual-network hydrogels (CS-GA/A-ß-CD) with snap-structure were designed to achieve curcumin immobilization, using gallic acid-grafted chitosan (CS-GA) and aldehyde-ß-cyclodextrin (A-ß-CD) crosslinked. A-ß-CD were able to achieve rapid dissolution (≥222.35 mg/mL H2O), and helped CS-GA/A-ß-CD achieve rapid gelation (≤66.23 s). By adjusting the ratio of aldehyde groups of A-ß-CD, mechanical properties and drug release can be controlled. CS-GA/A-ß-CD/Cur exhibited excellent antimicrobial properties against S. aureus, E. coli, and P. aeruginosa. In vivo experiments demonstrated that CS-GA/A-ß-CD/Cur achieved acute bacterial infection wound healing after 20th days, proving its great potential for wound dressing.

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