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1.
Food Hydrocoll ; 1592025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39429546

RESUMO

Inclusion complexes of ß-cyclodextrin (ß-CD) and tryptophan (Trp) were synthesized using an antisolvent approach, and fully characterized. Scanning electron microscope images proved the formation of the ß-CD/Trp NPs and the powder X-ray diffraction pattern indicated the formation of a crystalline channel-like structure for the ß-CD/Trp nanoparticles (NPs). The NPs of a ß-CD/Trp inclusion complex were used as a natural stabilizer at the oil/water interface of a Pickering emulsion. Pickering emulsions with an oil to water ratio of 1:1 (v:v) were obtained under high-speed homogenization and different mass ratios of the ß-CD to Trp (1:0, 1:0.1, 1:0.25, 1:0.5, 1:1), and at different pH levels (3, 5, 7, 9). At pH 9, when the ß-CD:Trp mass ratio was 1:0.1, the ß-CD/Trp NPs were hydrophilic, and the oil-in-water Pickering emulsions stabilized by those nanoparticles showed the highest storage stability: 180 days at room temperature. In contrast, when the emulsions were prepared at pH 5 with the weight ratios of either 1:0.1 or 1:1, ß-CD:Trp, the nanoparticles were hydrophobic and could be used to stabilize water-in-oil Pickering emulsions.

2.
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
3.
Int J Pharm ; 666: 124787, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39362296

RESUMO

Nanoparticles (NPs) have gained significant attention in recent years due to their potential applications in pharmaceutical formulations, drug delivery systems, and various biomedical fields. The versatility of colloidal NPs, including their ability to be tailored with various components and synthesis methods, enables drug delivery systems to achieve controlled release patterns, improved solubility, and increased bioavailability. The review discusses various types of NPs, such as nanocrystals, lipid-based NPs, and inorganic NPs (i.e., gold, silver, magnetic NPs), each offering unique advantages for drug delivery. Despite the promising potential of NPs, challenges such as physical instability and the need for surface stabilization remain. Strategies to overcome these challenges include the use of surfactants, polymers, and cyclodextrins (CDs). This review highlights the role of CDs in stabilizing colloidal NPs and enhancing drug solubility. The combination of CDs with NPs presents a synergistic approach that enhances drug delivery and broadens the range of biomedical applications. Additionally, the potential of CDs to enhance the stability and therapeutic efficacy of colloidal NPs, making them promising candidates for advanced drug delivery systems, is comprehensively reviewed.

4.
Luminescence ; 39(10): e4917, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39380243

RESUMO

This study introduces a remarkably simple, green, and highly sensitive inclusion complex based spectrofluorimetric method for analyzing two sodium glucose cotransporter-2 (SGLT2) inhibitors: empagliflozin (EGF) and dapagliflozin (DGF). The method utilizes beta-cyclodextrin (ß-CD) complexation to enhance the native fluorescence of EGF and DGF in aqueous solutions, resulting in 11.0-fold and 9.0-fold intensity increases, respectively. Fluorescence measurements were conducted at 301 nm emission following 230 nm excitation for both drugs. The method demonstrates excellent linearity (0.9994 for EGF and 0.9993 for DGF) over concentration ranges of 5.0-250.0 ng/mL and 10.0-300.0 ng/mL, with low detection limits of 1.05 and 1.38 ng/mL for EGF and DGF, respectively. The method's versatility was validated through successful application in pharmaceutical formulations, content uniformity testing, and biological fluids. This eco-friendly approach primarily uses water as a solvent and requires minimal reagents. The method's environmental impact was comprehensively evaluated using the analytical eco-scale, green analytical procedure index (GAPI), and analytical greenness metric (AGREE).


Assuntos
Compostos Benzidrílicos , Glucosídeos , Inibidores do Transportador 2 de Sódio-Glicose , Espectrometria de Fluorescência , beta-Ciclodextrinas , Inibidores do Transportador 2 de Sódio-Glicose/análise , Compostos Benzidrílicos/análise , Compostos Benzidrílicos/química , Glucosídeos/análise , beta-Ciclodextrinas/química , Humanos , Química Verde
5.
Biochim Biophys Acta Bioenerg ; 1866(1): 149516, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39357779

RESUMO

Recent patch-clamp studies of mitoplasts have challenged the traditional view that classical chemical uncoupling (by e.g. FCCP or DNP) is due to the protonophoric property of these substances themselves. These studies instead suggest that in brown-fat mitochondria, FCCP- and DNP-induced uncoupling is mediated through activation of UCP1 (and in other tissues by activation of the adenine nucleotide transporter). These studies thus advocate an entirely new paradigm for the interpretation of standard bioenergetic experiments. To examine whether these patch-clamp results obtained in brown-fat mitoplasts are directly transferable to classical isolated brown-fat mitochondria studies, we investigated the effects of FCCP and DNP in brown-fat mitochondria from wildtype and UCP1 KO mice, comparing the FCCP and DNP effects with those of a fatty acid (oleate), a bona fide activator of UCP1. Whereas the sensitivity of brown-fat mitochondria to oleate was much higher in UCP1-containing than in UCP1 KO mitochondria, there was no difference in sensitivity to FCCP and DNP between these mitochondria, neither in oxygen consumption rate nor in membrane potential studies. Correspondingly, the UCP1-dependent ability of GDP to competitively inhibit activation by oleate was not seen with FCCP and DNP. It would thus be premature to abandon the established bioenergetic interpretation of chemical uncoupler effects in classical isolated brown-fat mitochondria-and probably also generally in this type of mitochondrial study. Understanding the molecular and structural reasons for the different outcomes of mitoplast and mitochondrial studies is a challenging task.

6.
Sci Rep ; 14(1): 23046, 2024 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-39367103

RESUMO

Corneal ulcers, whether melting or indolent, are common in humans and companion animals. Treatment involves local administration of antibiotic eye drops and corneal healing drugs. Compared to traditional treatments for ulcerative keratitis, herbal medicines offer unique advantages, such as potent anti-inflammatory effects and inhibition of proinflammatory cytokines. Curcumin, extracted from the Curcuma Longa plant, possesses extensive pharmacological properties, such as anti-inflammatory, anti-cancer, and antioxidant properties, and is used in various medicines. In this study, we developed a novel ophthalmic drop hydrogel using a formulation of Curcumin NPs encapsulated with ß-cyclodextrin and hyaluronic acid, to accelerate corneal healing and improve the quality of healed structures. The formation of Curcumin NPs into Hyaluronic acid-based hydrogels was characterized by zeta, FTIR, and scanning electron microscope (SEM) analyses. A total of 25 healthy male New Zealand Albino rabbits were experimentally induced with ulcerative keratitis and treated individually with topical medication. Rabbits were divided into five groups. Fluorescein dye staining, corneal clarity score, Schirmer tear test, proinflammatory cytokine measurement, and pathologic factors assessments were used to evaluate the optimised Curcumin NPs with ß-cyclodextrin in Hyaluronic acid hydrogel. Our results demonstrated that the optimized Curcumin NPs with ß-cyclodextrin in hyaluronic acid hydrogel significantly reduced the frequency of medication administration compared to conventional therapies, enhancing the quality of healed structures and effectively treating ulcerative keratitis. All findings in this study provide new insight into designing and fabricating novel ophthalmic medicine for ulcerative keratitis for topical usage.


Assuntos
Úlcera da Córnea , Curcumina , Modelos Animais de Doenças , Ácido Hialurônico , Hidrogéis , Nanopartículas , Animais , Coelhos , Curcumina/farmacologia , Curcumina/química , Curcumina/administração & dosagem , Ácido Hialurônico/química , Nanopartículas/química , Hidrogéis/química , Úlcera da Córnea/tratamento farmacológico , Úlcera da Córnea/patologia , Masculino , Cicatrização/efeitos dos fármacos , Soluções Oftálmicas/química , Córnea/efeitos dos fármacos , Córnea/patologia , Córnea/metabolismo , beta-Ciclodextrinas/química , Citocinas/metabolismo
7.
J Sep Sci ; 47(20): e70004, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39466003

RESUMO

The excessive accumulation of heavy metals has adverse effects on the human body. Here, magnetic iron oxide-impregnated carboxymethyl-ß-cyclodextrin was synthesized. The synthesized material was employed as a magnetic solid-phase extracting adsorbent for specific heavy metals like lead (Pb), nickel (Ni), copper (Cu), and cobalt (Co). Characterization was performed by X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller, and Fourier-transform infrared spectroscopy. The analytical merits, like detection limits (Pb: 1.38 ng/mL, Ni: 0.5 ng/mL, Co: 0.14 ng/mL, and Cu: 0.55 ng/mL) and quantification limits (Pb: 4.14 ng/mL, Ni: 1.62 ng/mL, Co: 1.85 ng/mL, and Cu: 1.82 ng/mL) were calculated. Similarly, the preconcentration and enhancement factors (15) and relative standard deviation (Pb: 3.5, Ni: 0.92, Co: 2.7, and Cu: 1.5) were also calculated. The interfering study shows that the method is highly selective. For validation, it was applied to certified reference materials such as the Institute of Nuclear Chemistry and Technology ornamental Basma tobacco leaves and trace metal double addition 63.4 environmental water with good percent recovery values (92%-99%). Real water and food samples were also used with satisfactory (90%-99%) recovery results.


Assuntos
Contaminação de Alimentos , Metais Pesados , Extração em Fase Sólida , Poluentes Químicos da Água , beta-Ciclodextrinas , Metais Pesados/análise , Metais Pesados/isolamento & purificação , Metais Pesados/química , beta-Ciclodextrinas/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Contaminação de Alimentos/análise , Nanopartículas Magnéticas de Óxido de Ferro/química , Fenômenos Magnéticos , Adsorção , Tamanho da Partícula
8.
Beilstein J Org Chem ; 20: 2635-2643, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39445223

RESUMO

Cyclodextrins (CDs) are host systems with inherent capability for inclusion complex formation with various molecular entities, mostly hydrophobic substances. Host CDs are highly accommodative to water molecules as well and usually contain water in the native state. There is still an ongoing discussion on both the total number of water molecules and their preferred binding position inside the cavities of the CDs. To understand the hydration/dehydration properties of γ-CD (the largest of the three most abundant native CDs), the main experimental methods applied in this study were differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). By coupling these techniques with density functional theory (DFT) calculations we try to shed some light on the mechanism of the γ-CD hydration and to address some unanswered questions: (i) what are the preferable locations for water molecules in the macrocyclic cavity ("hot spots"); (ii) what are the major factors contributing to the stability of the water cluster in the CD interior; (iii) what type of interactions (i.e., water-water and/or water-CD walls) contribute to the stability of the water assemble; (iv) how does the mechanism of the γ-CD hydration compare with those of its α-CD and ß-CD counterparts.

9.
J Pharm Sci ; 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39447870

RESUMO

Use of solubilization carriers for poorly soluble drugs may disturb transmembrane absorption by lowering the activity of drug molecules, which is known as the solubility-permeability interplay. However, although many in vitro studies have indicated the negative impacts of use of solubilization carriers for oral absorption, in vivo studies that showed the interplay effect are limited. This study provides systematic in vitro, in situ, and in vivo investigation of the interplay effect of cyclodextrin using dexamethasone as a model drug. The evaluation methods included permeation through polymeric, artificial lipid, cell, and intestinal closed-loop membranes. Then, the results were compared with oral administration studies in mice and dogs. Although the interplay effect was clearly observed in the in vitro studies, no obvious interplay was found in the in vivo studies, suggesting that the interplay effect is more prominent in the in vitro permeation studies. Absence of in vivo interplay was attributed to the dilution effect in the gastrointestinal tract, interaction of the drug with living components, and clearance of the drug after membrane permeation. Overall, this investigation clearly demonstrated the applicability and limitations of in vitro permeation studies for predicting the interplay effects of solubilizers after the oral administration.

10.
Int J Pharm ; : 124848, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39447934

RESUMO

Dexamethasone (DXM) is a commonly used corticosteroid in the treatment of ocular inflammatory conditions that affect more and more people. The aim of this study was to evaluate the effect of the combination of hydroxypropyl-ß-cyclodextrin (HPBCD), in situ gelling formulations, and other mucoadhesive polymers, i.e., hydroxypropyl methylcellulose (HPMC) and zinc-hyaluronate (ZnHA), on permeation by applying in vitro and ex vivo ophthalmic permeation models. Additionally, gelling properties, in vitro drug release, and mucoadhesion were measured to determine the impact of these factors on permeation and ultimately on bioavailability. The results showed that GEL1 and GEL2 had an optimal gelling temperature, 36.3 ℃ and 34.6 ℃, respectively. Moreover, the combination of Poloxamer 407 (P407) with other polymers improved the mucoadhesion (GEL1: 1333.7 mN) compared with formulations containing only P407 (P12: 721.8 mN). Both HPBCD and the gel matrix had a considerable influence on the drug release and permeability of DXM, and the combination could facilitate the permeation into the aqueous humor. After 30 min of treatment, the DXM concentration in the aqueous humor was 1.16-1.37 µg∕mL in case of the gels, whereas DXM could not be detected when treated with the DXM suspension. The results of the experiments using an in vitro cell line indicated that the formulations could be considered safe for topical treatment of the eye. In conclusion, with application of a small amount of HPMC (0.2 % w∕w), the concentration of P407 could be reduced to 12 % w/w while maintaining the ideal gelling properties and gel structure without negatively affecting permeability compared with the formulation containing a higher amount of P407. Furthermore, the gel matrix may also provide programmed and elongated drug release.

11.
Arch Microbiol ; 206(11): 445, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39443369

RESUMO

Quercetin is a natural flavonoid with antioxidant, anti-inflammatory, and antibacterial properties. This work aimed to formulate quercetin-cyclodextrin microcapsules (QT-ß-CD) while examining their photodynamic antibacterial effects and underlying mechanisms in detail. Characterization of the QT-ß-CD was conducted using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The bacteriostatic effects of UV-A irradiation on Escherichia coli O157:H7 (E. coli O157:H7) were investigated. The photodynamic impact of QT-ß-CD was assessed by analyzing hydrogen peroxide (H2O2) production. The antimicrobial activity was further elucidated through examinations of cell membrane integrity, protein damage, changes in cellular motility, biofilm formation, and extracellular polysaccharide reduction. The effect of QT-ß-CD on LuxS and motA gene expression in E. coli O157:H7 was investigated by RT-qPCR. The findings demonstrated that QT-ß-CD exhibited potent photodynamic properties and functioned as an efficient photosensitizer, causing substantial damage to E. coli O157:H7 cells. These results underscore the potential of quercetin as an antimicrobial agent for food preservation.


Assuntos
Antibacterianos , Escherichia coli O157 , Quercetina , beta-Ciclodextrinas , Quercetina/farmacologia , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/efeitos da radiação , Antibacterianos/farmacologia , Antibacterianos/química , beta-Ciclodextrinas/farmacologia , Biofilmes/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Raios Ultravioleta , Testes de Sensibilidade Microbiana
12.
Environ Res ; 263(Pt 3): 120189, 2024 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-39433238

RESUMO

Pharmaceutical contaminants pose significant risks to ecosystems and human health, necessitating effective removal strategies. This research focuses on developing advanced adsorbents for removing pharmaceutical pollutants from the environment. Metal-organic frameworks (MOFs), specifically MIL-101(Cr) functionalized with biodegradable beta-cyclodextrin (ß-CDex), were investigated as potential nanocomposite adsorbents for the removal of ketorolac (KTRK), naproxen (NPXN), and tramadol (TRML). The study employed molecular simulations and density functional theory (DFT) calculations to explore the interactions between the pollutants and adsorbents. Analyses of DFT results, including electrostatic potential, ionization energy, density of states, and molecular orbital analysis, provided insights into the reactivity of pollutants and adsorbents. Additionally, the structural properties of the adsorbents, such as fractional free volume, radius of gyration, and system energies, were thoroughly examined. Molecular dynamics (MD) and Monte Carlo (MC) simulations were used to evaluate the adsorption capacities of MIL-101(Cr) for the target pharmaceutical pollutants. The results demonstrated the superior adsorption performance of the nanocomposite adsorbent, particularly for KTRK, with an adsorption energy of -1934 kcal/mol, compared to the pristine MIL-101(Cr), which had an adsorption energy of -1916 kcal/mol. This enhanced adsorption is attributed to the optimal molecular fit, guest-host solid interactions, and the selective encapsulation capabilities of ß-CDex. This research highlights the potential of MOF-based nanocomposites as effective and sustainable solutions for pharmaceutical pollution. By advancing the understanding of molecular interactions through simulations, this study contributes to developing innovative adsorbents for wastewater treatment and the protection of water resources.

13.
Curr Med Chem ; 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39440783

RESUMO

Cyclodextrin Metal-Organic Frameworks (CD MOFs) represent an innovative class of materials with remarkable properties and a broad range of applications. This review provides a comprehensive overview of the synthesis techniques, structural characterization, and diverse applications of CD-MOFs. By combining cyclodextrins (CDs) with metal-organic frameworks (MOFs), CD-MOFs are developed with enhanced functionality. The synthesis methods, including various metal sources, coordination modes, and post-synthesis modifications, are discussed alongside advanced structural characterization techniques like X-ray crystallography and spectroscopic methods. The unique characteristics of CD-MOFs, such as high specific surface area, tunable porosity, and customizable chemical structure, make them exceptional candidates for applications in gas adsorption, drug delivery, catalysis, sensing, and environmental remediation. Notably, CD-MOFs show significant promise as nanocarriers in drug delivery systems, offering improved therapeutic outcomes due to their efficient encapsulation and controlled release capabilities. The review highlights recent advancements and underscores the potential impact of CD-MOFs in driving future innovations across various scientific fields.

14.
Gels ; 10(10)2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39451298

RESUMO

This study aimed to develop and evaluate hydrogels containing a cyclodextrin complex with clove essential oil and other free volatile oils with antimicrobial properties (tea tree and rosemary essential oils), focusing on their pharmaco-technical and rheological characteristics. The formulations varied in the Carbopol 940 (a hydrophilic polymer) and volatile oils' concentrations. Rheological analysis indicated that the gels displayed pseudoplastic behavior, with the flow index (n) values below 1, ensuring appropriate consistency and handling. The results showed that increasing the Carbopol concentration significantly enhanced the yield stress, consistency index, and viscosity, with gel B, containing 1% Carbopol, 1.5% tea tree essential oil, and 1.5% rosemary essential oil, demonstrating optimal stability and rheological properties. At the same time, the concentration of volatile oils was found to modulate the gels' flow parameters, but their effect was less pronounced than that of the gel-forming polymer. Antimicrobial testing revealed that both gel B and gel E (containing 1% Carbopol, 2% tea tree essential oil, and 2% rosemary essential oil) exhibited antimicrobial activity against Gram-positive, Gram-negative bacteria, and Candida spp., with gel E showing superior efficacy against Candida tropicalis. The antimicrobial effects were likely influenced by the higher concentrations of tea tree and rosemary essential oils in gel E. Overall, the study demonstrates that the concentration of Carbopol 940 primarily determines the gel's rheological behavior, while volatile oil concentration modulates antimicrobial effectiveness.

15.
J Colloid Interface Sci ; 679(Pt B): 254-262, 2024 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-39454257

RESUMO

Relying on surpassing high theoretical capacity (3,865 mAh/g) and the lowest relative electrode potential (0 V vs. metallic Li), lithium metal batteries (LMBs) have been regarded as the "holy grail" of next-generation energy storage technology. Whereases, the instability of pristine solid electrolyte interphase (SEI) layers and the disorderly growth of lithium dendrites are still significant challenges to the commercialisation of LMBs. In this study, a novel approach is introduced to homogenise Li deposition by incorporating an environmentally friendly electrolyte additive, gamma-cyclodextrin (γ-CD), in ether-based electrolytes. Through host-guest interactions, γ-CD additives not only form inclusion complexes to improve Li+ transference number to 0.86 but also encapsulate TFSI- anions and other solvent molecules within the "cavity effect" to relieve unfavourable solvent effect. Electrochemical characterisations demonstrate that introducing 1 wt% γ-CD elevates the oxidation decomposition voltage of ether electrolytes to 4.15 V, thereby inhibiting the decomposition of ether electrolytes and reducing the fracture of SEI layers. According to reduce the nucleate potential, the Li//Cu half battery exhibits improved stability for 100 cycles, with an improved average Coulombic efficiency (CE) maintained above 98.4 %. Even if applied at high current densities of 5.0 mA cm-2 for a capacity of 1.0 mAh cm-2, the Li//Li symmetric battery can cycle for over 800 h, and the Li//Li4Ti5O12 (LTO) full battery retains 98.8 % of the initial capacity after 1,400 cycles.

16.
Chemistry ; : e202403232, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39382344

RESUMO

Amphiphilic supramolecular materials based on biodegradable cyclodextrins (CDs) have been known to self-assemble into different types of thermotropic liquid crystals, including smectic and hexagonal columnar mesophases. Previous studies on amphiphilic CDs bearing 14 aliphatic chains at the primary face and 7 oligoethylene glycol (OEG) chains at the secondary face showed that the stability of the mesophase can be rationally tuned through implemation of terminal functional groups to the OEG chains. Here, we report the syntheses of first examples of crown ether-functionalized amphiphilic cyclodextrins that unexpectedly form thermotropic bicontinuous cubic phases. This constitutes the first reported examples of cyclodextrins forming such phases, which are potentially capable of 3D ion transport. Lithium composites were made to assess lithium conduction in the material. XRD revealed the added lithium salt destabilizes the cubic phase in favour of the smectic phase. Solid-state NMR studies showed that these materials conduct lithium ions with a very low activation energy.

17.
Mol Pharm ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353049

RESUMO

Melanoma is an aggressive skin cancer notorious for high levels of drug resistance. Additionally, current treatments such as immunotherapies are often associated with numerous adverse side effects. The use of nitric oxide (NO) may represent an attractive treatment for melanoma due to NO's various anticancer properties, unlikeliness to foster resistance, and limited toxicity toward healthy tissues. The anticancer effects of chemical NO donors have been explored previously but with limited understanding of the needed characteristics for exerting optimal antimelanoma activity. Herein, the in vitro therapeutic efficacy of three macromolecular NO donor systems (i.e., cyclodextrin, mesoporous silica nanoparticles, and hyaluronic acid) with tunable NO-release kinetics was explored by evaluating skin permeation along with toxicity against melanoma and healthy skin cells. Cytotoxicity against melanoma cells was dependent on NO payload and not donor identity or NO-release kinetics. In contrast, cytotoxicity against healthy cells was primarily influenced by the macromolecular NO donor, with cyclodextrin- and hyaluronic acid-based NO donors having the highest therapeutic indices. In vitro skin permeation was influenced by both the size and charge of the NO donor, with smaller, more neutral donors resulting in greater permeation. A Pluronic F127 organogel was optimized for the delivery of a cyclodextrin-based NO donor. Delivery of the NO donor in this manner resulted in increased in vitro skin permeation and reduced tumor growth in an in vivo model.

18.
Foods ; 13(19)2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39410113

RESUMO

Hemin, a heme-like compound with significant biological activity, shows promise as an iron supplement for humans. Nonetheless, its poor solubility in water greatly impedes its absorption and utilization. To surmount this obstacle, researchers have chosen various cyclodextrins with distinct cavity sizes and derivative groups to act as hosts, forming inclusion complexes with hemin chloride. Among these, γ-cyclodextrin has been identified as the optimal carrier, based on a thorough evaluation of its encapsulation efficiency, solubility, and molecular docking. Multiple characterization techniques further confirmed the formation of these inclusion complexes. Results from IEC-6 cell experiments indicated that the cytotoxicity of the inclusion complexes was lower than that of FeSO4. Static and dynamic gastrointestinal simulation digestion systems were established, and the results showed that the bioavailability of the inclusion complex was significantly higher than that of raw hemin. Additionally, only about 0.29% of hemin chloride is digested by gastric enzymes, whereas 9.52% is digested by pancreatic enzymes in the static gastrointestinal simulation digestion system, with similar outcomes observed in the dynamic system. These findings suggest that targeted digestion in the intestine significantly enhances the bioavailability of hemin chloride by forming inclusion complexes in vitro.

19.
J Chromatogr A ; 1736: 465394, 2024 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-39366032

RESUMO

Cyclodextrin-based stationary phases are important chiral selectors in liquid chromatography. These chiral selectors are most commonly used in the reversed-phase mode because native cyclodextrin assumes a torus conformation with a hydrophobic cavity, facilitating inclusion complexation in aqueous environments. However, the value of native and aliphatic-derivatized cyclodextrins in other modes, such as the normal phase liquid chromatography (NPLC) or super/subcritical fluid chromatography (SFC), remains unexplored. In this work, we report chiral separations of pharmaceutically relevant compounds with the 1,4-dihydropyridine (DHP) scaffold on a 2-hydroxypropyl-ß-cyclodextrin (CD-RSP) stationary phase in NPLC and SFC modes. Although CD-RSP is conventionally considered only effective in the reversed-phase mode, we show that these compounds tend to separate better in other modes. This is particularly apparent for analytes with hydrogen-bonding moieties. We propose that the separation mechanism primarily depends on external adsorption rather than inclusion complexation. The negligible impact of a complexation-competitive additive on retention in non-aqueous modes further supports this claim. Additionally, van Deemter analysis demonstrated the efficiency and environmental benefit of using this stationary phase in the SFC mode, further highlighting the promise of aliphatic derivatized cyclodextrin stationary phases for greener separations.


Assuntos
Cromatografia com Fluido Supercrítico , Ciclodextrinas , Di-Hidropiridinas , Estereoisomerismo , Di-Hidropiridinas/química , Di-Hidropiridinas/isolamento & purificação , Ciclodextrinas/química , Cromatografia com Fluido Supercrítico/métodos , Cromatografia Líquida/métodos , Ligação de Hidrogênio , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina/química , Adsorção
20.
Int J Mol Sci ; 25(19)2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39409039

RESUMO

Kidney dysfunction leads to the retention of metabolites within the blood that are not effectively cleared with conventional hemodialysis. Magnetic nanoparticle (MNP)-based absorbents have inherent properties that make them amenable to capturing toxins in the blood, notably a large surface area that can be chemically modified to enhance toxin capture and the ability to be easily collected from the blood using an external magnetic field. Cyclodextrins (CDs) present a chemical structure that facilitates the binding of small molecules. However, the hemocompatibility of MNPs modified with films composed of different native types of CDs (α, ß, or γ) has not yet been investigated, which is information crucial to the potential clinical application of MNPs to supplement hemodialysis. To this end, films of α-, ß-, or γ-CDs were formed on MNPs and characterized. The impact of these films on the adsorbed protein structure, composition of key adsorbed proteins, and clotting kinetics were evaluated. It was found that modified MNPs did not significantly affect the secondary structure of some proteins (albumin, lysozyme, α-lactalbumin). The adsorbed proteome from platelet-poor human plasma was evaluated as a function of film properties. Compared to non-modified nanoparticles, CD-modified MNPs exhibited a significant decrease in the adsorbed protein per surface area of MNPs. The immunoblot results showed variations in the adsorption levels of C3, fibrinogen, antithrombin, Factor XI, and plasminogen across CD-modified MNPs. The hemocompatibility experiments showed that CD-modified MNPs are compatible with human whole blood, with no significant impact on platelet activation, hemolysis, or hemostasis.


Assuntos
Nanopartículas de Magnetita , Humanos , Adsorção , Nanopartículas de Magnetita/química , Ciclodextrinas/química , Coagulação Sanguínea/efeitos dos fármacos , Teste de Materiais , gama-Ciclodextrinas/química , Materiais Biocompatíveis/química , beta-Ciclodextrinas/química , alfa-Ciclodextrinas/química
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