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1.
Carbohydr Polym ; 342: 122203, 2024 Oct 15.
Article in English | MEDLINE | ID: mdl-39048182

ABSTRACT

Red fluorescent hydrogels possessing injectable and self-healing properties have widespread potential in biomedical field. It is still a challenge to achieve a biomacromolecules based dynamic hydrogels simultaneously combining with excellent red fluorescence, good mechanical properties, and biocompatibility. Here we first explore hydrophilic inclusion complex of (R-CDs@α-CD) derived from hydrophobic red fluorescent carbon dots (R-CDs) and α-cyclodextrin (α-CD), and then achieved a red fluorescent and dynamic polysaccharide R-CDs@α-CD/CEC-l-OSA hydrogel. The nanocomposite hydrogel can be fabricated through controlled doping of red fluorescent R-CDs@α-CD into dynamic polymer networks, taking reversibly crosslinked N-carboxyethyl chitosan (CEC) and oxidized sodium alginate (OSA) as an example. The versatile red fluorescent hydrogel simultaneously combines the features of injection, biocompatibility, and augmented mechanical properties and self-healing behavior, especially in rapid self-recovery even after integration. The R-CDs@α-CD uniformly dispersed into dynamic hydrogel played the role of killing two birds with one stone, that is, endowing red emission of a hydrophilic fluorescent substance, and improving mechanical and self-healing properties as a dynamic nano-crosslinker, via forming hydrogen bonds as reversible crosslinkings. The novel red fluorescent and dynamic hydrogel based on polysaccharides is promising for using as biomaterials in biomedical field.


Subject(s)
Alginates , Carbon , Chitosan , Hydrogels , Nanocomposites , Quantum Dots , Alginates/chemistry , Chitosan/chemistry , Carbon/chemistry , Nanocomposites/chemistry , Hydrogels/chemistry , Quantum Dots/chemistry , Quantum Dots/toxicity , Fluorescent Dyes/chemistry , alpha-Cyclodextrins/chemistry , Biocompatible Materials/chemistry , Animals , Hydrophobic and Hydrophilic Interactions
2.
Int J Mol Sci ; 25(14)2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39063225

ABSTRACT

Tyramine (TRM) is a biogenic catecholamine neurotransmitter, which can trigger migraines and hypertension. TRM accumulated in foods is reduced and detected using additive cyclodextrins (CDs) while their association characteristics remain unclear. Here, single-crystal X-ray diffraction and density functional theory (DFT) calculation have been performed, demonstrating the elusive pseudopolymorphs in ß-CD inclusion complexes with TRM base/HCl, ß-CD·0.5TRM·7.6H2O (1) and ß-CD·TRM HCl·4H2O (2) and the rare α-CD·0.5(TRM HCl)·10H2O (3) exclusion complex. Both 1 and 2 share the common inclusion mode with similar TRM structures in the round and elliptical ß-CD cavities, belong to the monoclinic space group P21, and have similar herringbone packing structures. Furthermore, 3 differs from 2, as the smaller twofold symmetry-related, round α-CD prefers an exclusion complex with the twofold disordered TRM-H+ sites. In the orthorhombic P21212 lattice, α-CDs are packed in a channel-type structure, where the column-like cavity is occupied by disordered water sites. DFT results indicate that ß-CD remains elliptical to suitably accommodate TRM, yielding an energetically favorable inclusion complex, which is significantly contributed by the ß-CD deformation, and the inclusion complex of α-CD with the TRM aminoethyl side chain is also energetically favorable compared to the exclusion mode. This study suggests the CD implications for food safety and drug/bioactive formulation and delivery.


Subject(s)
Tyramine , Tyramine/chemistry , beta-Cyclodextrins/chemistry , Models, Molecular , Cyclodextrins/chemistry , alpha-Cyclodextrins/chemistry , Density Functional Theory , Crystallography, X-Ray , X-Ray Diffraction
3.
Biomacromolecules ; 25(8): 4697-4714, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-38995854

ABSTRACT

Stimulating the release of small nanoparticles (NPs) from a larger NP via the application of an exogenous stimulus offers the potential to address the different size requirements for circulation versus penetration that hinder chemotherapeutic drug delivery. Herein, we report a size-switching nanoassembly-based drug delivery system comprised of ultrasmall starch nanoparticles (SNPs, ∼20-50 nm major size fraction) encapsulated in a poly(oligo(ethylene glycol) methyl ether methacrylate) nanogel (POEGMA, ∼150 nm major size fraction) cross-linked via supramolecular PEG/α-cyclodextrin (α-CD) interactions. Upon heating the nanogel using a non-invasive, high-intensity focused ultrasound (HIFU) trigger, the thermoresponsive POEGMA-CD nanoassemblies are locally de-cross-linked, inducing in situ release of the highly penetrative drug-loaded SNPs. HIFU triggering increased the release of nanoassembly-loaded DOX from 17 to 37% after 3 h, a result correlated with significantly more effective tumor killing relative to nanoassemblies in the absence of HIFU or drug alone. Furthermore, 1.5× more total fluorescence was observed inside a tumor spheroid when nanoassemblies prepared with fluorophore-labeled SNPs were triggered with HIFU relative to the absence of HIFU. We anticipate this strategy holds promise for delivering tunable doses of chemotherapeutic drugs both at and within a tumor site using a non-invasive triggering approach.


Subject(s)
Doxorubicin , Polyethylene Glycols , Humans , Polyethylene Glycols/chemistry , Doxorubicin/chemistry , Doxorubicin/pharmacology , Doxorubicin/administration & dosage , Nanogels/chemistry , Nanoparticles/chemistry , alpha-Cyclodextrins/chemistry , Drug Delivery Systems/methods , Antibiotics, Antineoplastic/chemistry , Antibiotics, Antineoplastic/administration & dosage , Antibiotics, Antineoplastic/pharmacology , Animals , Drug Carriers/chemistry , Cell Line, Tumor , Polyethyleneimine/chemistry
4.
Adv Mater ; 36(31): e2403551, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38837826

ABSTRACT

Conventional wound closure methods, including sutures and tissue adhesives, present significant challenges for self-care treatment, particularly in the context of bleeding wounds. Existing stimuli-responsive contractile materials designed for autonomous wound closure frequently lack sufficient output work density to generate the force needed to bring the wound edges into proximity or necessitate stimuli that are not compatible with the human body. Here, semi-transparent, flexible, and water-responsive shrinkable films, composed of poly(ethylene oxide) and α-cyclodextrin, are reported. These films exhibit remarkable stability under ambient conditions and demonstrate significant contraction (≈50%) within 6 s upon exposure to water, generating substantial contractile stress (up to 6 MPa) and output work density (≈1028 kJ m-3), which is 100 times larger than that of conventional hydrogel and 25 times larger than that of skeletal muscles. Remarkably, upon hydration, these films are capable of lifting objects 10 000 times their own weight. Leveraging this technology, water-shrink tapes, which, upon contact with water, effectively constrict human skin and autonomously close bleeding wounds in animal models within 10 seconds, are developed further. This work offers a novel approach to skin wound management, showing significant potential for emergency and self-care scenarios.


Subject(s)
Polyethylene Glycols , Water , alpha-Cyclodextrins , alpha-Cyclodextrins/chemistry , Polyethylene Glycols/chemistry , Water/chemistry , Humans , Animals , Wound Healing/drug effects , Skin , Wound Closure Techniques
5.
Int J Pharm ; 660: 124379, 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-38925235

ABSTRACT

Nanogels are aqueous dispersions of hydrogel particles formed by physically or chemically cross-linked polymer networks of nanoscale size. Herein, we devised a straightforward technique to fabricate a novel class of physically cross-linked nanogels via a self-assembly process in water involving α-cyclodextrin and a mannose molecule that was hydrophobically modified using an alkyl chain. The alkyl chain-modified mannose was synthesized in five steps, starting with D-mannose. Subsequently, nanogels were formed by subjecting α-cyclodextrin and the hydrophobically modified mannose to magnetic stirring in water. By adjusting the mole ratio between the hydrophobically modified mannose and α-cyclodextrin, nanogels with an average 100-150 nm diameter were obtained. Physicochemical and structural analyses by 1H NMR and X-ray diffraction unveiled a supramolecular and hierarchical mechanism underlying the creation of these nanogels. The proposed mechanism of nanogel formation involves two distinct steps: initial interaction of hydrophobically modified mannose with α-cyclodextrin resulting in the formation of inclusion complexes, followed by supramolecular interactions among these complexes, ultimately leading to nanogel formation after 72 h of stirring. We demonstrated the nanogels' ability to encapsulate a short peptide ([p-tBuF2, R5]SHf) as a water-soluble drug model. This discovery holds promise for potentially utilizing these nanogels in drug delivery applications.


Subject(s)
Hydrophobic and Hydrophilic Interactions , Mannose , alpha-Cyclodextrins , Mannose/chemistry , alpha-Cyclodextrins/chemistry , Nanogels/chemistry , Peptides/chemistry , Polyethylene Glycols/chemistry , Particle Size , Solubility
6.
Carbohydr Polym ; 338: 122205, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38763727

ABSTRACT

Developing multifunctional films with antibacterial, antioxidant, and sustained-release properties is a robust strategy for preventing contamination of perishable fruits by foodborne microorganisms. This study engineered a sustained-release biodegradable antibacterial film loaded with EGCG (Pickering emulsion (PE)/α-Cyclodextrin (α-CD)/Konjac glucomannan (KGM)) through multi-strategy cross-linking for fruit preservation. EGCG is stabilized using PE and incorporated into the α-CD/KGM inclusion compound; the unique structure of α-CD enhances EGCG encapsulation, while KGM provides the film toughness and surface adhesion. The composite film's physicochemical properties, antioxidant, bacteriostatic and biodegradability were studied. Results showed that Pickering emulsions with 3 % oil phase exhibited excellent stability. Moreover, α-CD introduction increased the loading and sustained release of EGCG from the film, and its concentration significantly affected the light transmission, thermal stability, mechanical strength, mechanical characteristics and antioxidant capacity of the composite membrane. Antioxidant and antimicrobial activities of the composite film increased significantly with increasing α-CD concentration. Application of the film to tomatoes and strawberries effectively inhibited Escherichia coli and Staphylococcus aureus growth, prolonging the shelf-life of the fruits. Notably, the composite film exhibits superior biodegradability in soil. This EGCG-loaded PE/α-CD/KGM composite film is anticipated to be a multifunctional antimicrobial preservation material with sustained-release properties and biodegradable for perishable food applications.


Subject(s)
Anti-Bacterial Agents , Antioxidants , Catechin , Emulsions , Escherichia coli , Fruit , Mannans , alpha-Cyclodextrins , alpha-Cyclodextrins/chemistry , Catechin/analogs & derivatives , Catechin/chemistry , Catechin/pharmacology , Mannans/chemistry , Mannans/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Fruit/chemistry , Emulsions/chemistry , Antioxidants/chemistry , Antioxidants/pharmacology , Escherichia coli/drug effects , Food Preservation/methods , Staphylococcus aureus/drug effects , Food Packaging/methods , Microbial Sensitivity Tests , Cross-Linking Reagents/chemistry , Drug Liberation
7.
Int J Mol Sci ; 25(10)2024 May 17.
Article in English | MEDLINE | ID: mdl-38791510

ABSTRACT

α-CD:N2O "host-guest" type complexes were formed by a simple solid-gas reaction (N2O sorption into α-CD) under different gas pressures and temperatures. The new N2O inclusion method applied in the present study was compared with the already known technique based on the crystallization of clathrates from a water solution of α-CD saturated with N2O. A maximum storage capacity of 4.5 wt.% N2O was achieved when charging the cyclodextrin from a gas phase. The amount of included gas decreases to 1.3 wt.% when the complex is stored in air at 1 atm and room temperature, analogous to that achieved by the crystallization of α-CD:N2O. Furthermore, it was shown that the external coordination of N2O to either the upper or lower rim of α-CD without hydration water displacement is the preferred mode of binding, due to hydrogen bonds with neighboring -OH groups from the host macrocycle and three of the hydration water molecules nearby. The capacity of α-CD to store N2O and the thermal stability of the α-CD:N2O complex demonstrated promising applications of these types of complexes in food and beverages.


Subject(s)
alpha-Cyclodextrins , alpha-Cyclodextrins/chemistry , Hydrogen Bonding , Temperature , Nitrogen Dioxide/chemistry , Water/chemistry , Adsorption
8.
J Agric Food Chem ; 72(18): 10655-10664, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38661642

ABSTRACT

Authenticating whole wheat foods poses a significant challenge for both the grain industry and consumers. Alkylresorcinols (ARs), serving as biomarkers of whole wheat, play a crucial role in assessing the authenticity of whole wheat foods. Herein, we introduce a novel molecularly imprinted electrochemical sensor with modifications involving a molecularly imprinted polymer (MIP) and MXene nanosheets, enabling highly sensitive and selective detection of ARs. Notably, we specifically chose 5-heneicosylresorcinol (AR21), the predominant homologue in whole wheat, as the template molecule. α-Cyclodextrin and acrylamide served as dual functional monomers, establishing a robust multiple interaction between the MIP and AR21. As a result, the sensor exhibited a wide linear range of 0.005 to 100 µg·mL-1 and a low detection limit of 2.52 ng·mL-1, demonstrating exceptional selectivity and stability. When applied to commercial whole wheat foods, the assay achieved satisfactory recoveries and accuracy, strongly validating the practicality and effectiveness of this analytical technique.


Subject(s)
Electrochemical Techniques , Food Contamination , Molecular Imprinting , Resorcinols , Triticum , alpha-Cyclodextrins , Resorcinols/chemistry , Resorcinols/analysis , Triticum/chemistry , alpha-Cyclodextrins/chemistry , Electrochemical Techniques/methods , Electrochemical Techniques/instrumentation , Food Contamination/analysis , Limit of Detection
9.
Health Phys ; 127(3): 365-372, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38206086

ABSTRACT

ABSTRACT: To discharge waste liquid containing radioactive iodine into sewage systems, long-term storage or dilution with a large amount of water may be required until the radioactivity concentration reduces below the standard value. Processing the waste liquid could be easier if radioactive iodine could be separated from the water. This study verified the effectiveness of superabsorbent polymer and α-cyclodextrin as treatment agents to separate radioactive iodine from waste liquids. Sodium iodide (Na 125 I) was added to purified water and artificial urine to prepare simulated waste liquids containing iodine equivalent to the urine of patients treated with radioactive iodine. The as-prepared simulated waste liquid was poured into a container with superabsorbent polymer and left for 90 d. The residual iodine rate in the simulated waste liquid was estimated by measuring 125 I radioactivity. When the water was sufficiently dried, residual iodine rates on day 15 were 0.102 and 0.884 in the simulated waste liquids comprising purified water and artificial urine, respectively. The simulated waste liquid comprising purified water with 5% α-cyclodextrin absorbed by 1 g of superabsorbent polymer had a residual rate of 0.980. Moreover, the residual rate of simulated waste liquid comprising artificial urine with 2% α-cyclodextrin absorbed by 1 g of SAP was 0.949. Superabsorbent polymer combined with α-cyclodextrin was an effective treatment agent for separating radioactive iodine from waste liquids.


Subject(s)
Feasibility Studies , Iodine Radioisotopes , alpha-Cyclodextrins , alpha-Cyclodextrins/chemistry , Polymers/chemistry , Humans , Radioactive Waste/analysis , Water Pollutants, Radioactive/isolation & purification , Water Pollutants, Radioactive/analysis
10.
Nature ; 624(7991): 295-302, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38092907

ABSTRACT

Connecting different electronic devices is usually straightforward because they have paired, standardized interfaces, in which the shapes and sizes match each other perfectly. Tissue-electronics interfaces, however, cannot be standardized, because tissues are soft1-3 and have arbitrary shapes and sizes4-6. Shape-adaptive wrapping and covering around irregularly sized and shaped objects have been achieved using heat-shrink films because they can contract largely and rapidly when heated7. However, these materials are unsuitable for biological applications because they are usually much harder than tissues and contract at temperatures higher than 90 °C (refs. 8,9). Therefore, it is challenging to prepare stimuli-responsive films with large and rapid contractions for which the stimuli and mechanical properties are compatible with vulnerable tissues and electronic integration processes. Here, inspired by spider silk10-12, we designed water-responsive supercontractile polymer films composed of poly(ethylene oxide) and poly(ethylene glycol)-α-cyclodextrin inclusion complex, which are initially dry, flexible and stable under ambient conditions, contract by more than 50% of their original length within seconds (about 30% per second) after wetting and become soft (about 100 kPa) and stretchable (around 600%) hydrogel thin films thereafter. This supercontraction is attributed to the aligned microporous hierarchical structures of the films, which also facilitate electronic integration. We used this film to fabricate shape-adaptive electrode arrays that simplify the implantation procedure through supercontraction and conformally wrap around nerves, muscles and hearts of different sizes when wetted for in vivo nerve stimulation and electrophysiological signal recording. This study demonstrates that this water-responsive material can play an important part in shaping the next-generation tissue-electronics interfaces as well as broadening the biomedical application of shape-adaptive materials.


Subject(s)
Electrophysiology , Polymers , Water , Animals , alpha-Cyclodextrins/chemistry , Electrodes , Electrophysiology/instrumentation , Electrophysiology/methods , Electrophysiology/trends , Heart , Muscles , Polyethylene Glycols/chemistry , Polymers/chemistry , Silk/chemistry , Spiders , Water/chemistry , Hydrogels/chemistry , Electronics/instrumentation , Electronics/methods , Electronics/trends
11.
Carbohydr Polym ; 316: 121070, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37321712

ABSTRACT

This study aimed to evaluate the effect of thiolated α-cyclodextrin (α-CD-SH) on the cellular uptake of its payload. For this purpose, α-CD was thiolated using phosphorous pentasulfide. Thiolated α-CD was characterized by FT-IR and 1H NMR spectroscopy, differential scanning calorimetry (DSC), and powder X-ray diffractometry (PXRD). Cytotoxicity of α-CD-SH was evaluated on Caco-2, HEK 293, and MC3T3 cells. Dilauryl fluorescein (DLF) and coumarin-6 (Cou) serving as surrogates for a pharmaceutical payload were incorporated in α-CD-SH, and cellular uptake was analyzed by flow cytometry and confocal microscopy. Endosomal escape was investigated by confocal microscopy and hemolysis assay. Results showed no cytotoxic effect within 3 h, while dose-dependent cytotoxicity was observed within 24 h. The cellular uptake of DLF and Cou was up to 20- and 11-fold enhanced by α-CD-SH compared to native α-CD, respectively. Furthermore, α-CD-SH provided an endosomal escape. According to these results, α-CD-SH is a promising carrier to shuttle drugs into the cytoplasm of target cells.


Subject(s)
Drug Carriers , alpha-Cyclodextrins , Humans , Drug Carriers/toxicity , Drug Carriers/chemistry , alpha-Cyclodextrins/pharmacology , alpha-Cyclodextrins/chemistry , Caco-2 Cells , Spectroscopy, Fourier Transform Infrared , HEK293 Cells , Solubility , Calorimetry, Differential Scanning , X-Ray Diffraction
12.
Carbohydr Polym ; 297: 120002, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36184134

ABSTRACT

Low molecular weight heparin (LMWH), an anionic polysaccharide, has been widely used as a clinical anticoagulant. However, repeated subcutaneous injection is sometimes required due to its short half-life. To reduce the dosing frequency, the injectable polypseudorotaxane hydrogel was fabricated by inclusion complexation formation between Tween 80 and α-Cyclodextrin (αCD) for sustained release of LMWH. The physicochemical properties of such hydrogel were characterized by SEM, XRD, DSC, and FTIR. This hydrogel showed shear-thinning and thixotropic behavior and was easily injected through standard syringe needles. The gelation time, mechanical strength, shear viscosity, in vitro drug release rate, in vitro hydrogel dissolution rate, and in vivo hydrogel retention could be tuned by αCD concentration in the hydrogel. In vivo safety evaluation indicated that the polypseudorotaxane hydrogel was biocompatible. Most importantly, this polypseudorotaxane hydrogel could sustain release of LMWH after subcutaneous injection.


Subject(s)
alpha-Cyclodextrins , Anticoagulants/pharmacology , Cyclodextrins , Delayed-Action Preparations , Heparin, Low-Molecular-Weight , Hydrogels/chemistry , Poloxamer , Polysorbates , Rotaxanes , alpha-Cyclodextrins/chemistry
13.
Carbohydr Res ; 520: 108601, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35834859

ABSTRACT

Crystalline products of vapor diffusion of an alcoholic solution of 1R,4R-camphor into an aqueous solution of α-cyclodextrin were prepared and subjected to X-ray structure analysis. Two different forms were obtained: a dimeric cavity formed by head-to-head association of cyclodextrin (phase A), and a complex set of monomeric cavities (phase B). Both contain camphor molecules orientationally disordered inside cavities. The structures are solvated by mixtures of water and ethanol. The structures significantly differ in chemical stabilities. Whilst phase A is relatively stable with respect to guest desorption, phase B rapidly reacts to change of its chemical environment manifested by cracking of crystals in solution. The phenomenon has been recorded and a short movie is included in the supplementary data.


Subject(s)
Cyclodextrins , alpha-Cyclodextrins , Camphor/chemistry , Cyclodextrins/chemistry , Water , alpha-Cyclodextrins/chemistry
14.
Int J Mol Sci ; 23(2)2022 Jan 08.
Article in English | MEDLINE | ID: mdl-35054867

ABSTRACT

Pseudopolyrotaxanes (PPRs) are supramolecular structures consisting of macrocycles able to thread on a linear polymer chain in a reversible, non-covalent way, often referred to in the literature as "molecular necklaces". While the synthesis and reaction mechanisms of these structures in solution have been widely described, their solvent-free production has received little attention, despite the advantages that this route may offer. We propose in this work a kinetic mechanism that describes the PPR formation in the solid phase as a process occurring in two consecutive stages. This mechanism has been used to investigate the spontaneous formation of a PPR that occurs when grinding α-Cyclodextrin (α-CD) with polyethylene glycol (PEG). In the threading stage, the inclusion of the polymer and subsequent release of the water molecules lodged in the cavity of the macrocycle cause vibrational changes that are reflected in the time-dependence of the FTIR-ATR spectra, while the further assembly of PPRs to form crystals produces characteristic reflections in the XRD patterns, due to the channel-like arrangement of CDs, that can be used to track the formation of the adduct in crystalline form. The effects that working variables have on the kinetics of the reaction, such as temperature, feed ratio, molar mass of the polymer and the introduction of an amorphous block in the polymer structure, have been investigated. The rate constants of the threading step increase with the temperature and the activation energy of the process increases at lower proportions of CD to PEG. This is attributed to the lower degree of covering of the polymer chain with CDs that reduces the hydrogen-bonding driven stabilization between adjacent macrocycles. The formation of crystalline PPR, which takes place slowly at room temperature, is markedly promoted at higher temperatures, with lower proportions of CD favoring both the formation and the growth of the crystals. The molar mass of the polymer does not modify the typical channel-like arrangement of packed PPRs but the conversion into crystalline PPR diminishes when using PEG1000 instead of PEG400. At a microscopic level, the crystals arrange into lamellar structures, in the order of hundreds of nm, embedded in an amorphous-like matrix. The introduction of a polypropylene oxide block in the structure of the polymer (Pluronic L62) renders poorer yields and a considerable loss of crystallinity of the product of the reaction. The methodology here proposed can be applied to the general case of inclusion complexes of CDs with drugs in the solid phase, or to multicomponent systems that contain polymers as excipients in pharmaceutical formulations along with CDs.


Subject(s)
Cyclodextrins/chemistry , Poloxamer/chemistry , Polyethylene Glycols/chemistry , Rotaxanes/chemistry , Solvents/chemistry , Crystallization , Kinetics , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction , alpha-Cyclodextrins/chemistry
15.
Biochim Biophys Acta Biomembr ; 1864(1): 183774, 2022 02 01.
Article in English | MEDLINE | ID: mdl-34534531

ABSTRACT

Methods for efficient cyclodextrin-induced lipid exchange have been developed in our lab. These make it possible to almost completely replace the lipids in the outer leaflet of artificial membranes or the plasma membranes of living cells with exogenous lipids. Lipid replacement/substitution allows detailed studies of how lipid composition and asymmetry influence the structure and function of membrane domains and membrane proteins. In this review, we both summarize progress on cyclodextrin exchange in cells, mainly by the use of methyl-alpha cyclodextrin to exchange phospholipids and sphingolipids, and discuss the issues to consider when carrying out lipid exchange experiments upon cells. Issues that impact interpretation of lipid exchange are also discussed. This includes how overly naïve interpretation of how lipid exchange-induced changes in domain formation can impact protein function.


Subject(s)
Membrane Lipids/genetics , Membrane Microdomains/genetics , Phospholipids/genetics , alpha-Cyclodextrins/chemistry , Lipid Metabolism/genetics , Membrane Lipids/chemistry , Membrane Microdomains/chemistry , Membrane Proteins/chemistry , Membrane Proteins/genetics , Mutation, Missense/genetics , Phospholipids/chemistry
16.
Eur Rev Med Pharmacol Sci ; 25(1 Suppl): 90-100, 2021 12.
Article in English | MEDLINE | ID: mdl-34890039

ABSTRACT

OBJECTIVE: The aim of the study was to show the effect that two naturally occurring compounds, a cyclodextrin and hydroxytyrosol, can have on the entry of SARS-CoV-2 into human cells. MATERIALS AND METHODS: The PubMed database was searched to retrieve studies published from 2000 to 2020, satisfying the inclusion criteria. The search keywords were: SARS-CoV, SARS-CoV-2, coronavirus, lipid raft, endocytosis, hydroxytyrosol, cyclodextrin. Modeling of alpha-cyclodextrin and hydroxytyrosol were done using UCSF Chimera 1.14. RESULTS: The search results indicated that cyclodextrins can reduce the efficiency of viral endocytosis and that hydroxytyrosol has antiviral properties. Bioinformatic docking studies showed that alpha-cyclodextrin and hydroxytyrosol, alone or in combination, interact with the viral spike protein and its host cell receptor ACE2, thereby potentially influencing the endocytosis process. CONCLUSIONS: Hydroxytyrosol and alpha-cyclodextrin can be useful against the spread of SARS-CoV-2.


Subject(s)
Phenylethyl Alcohol/analogs & derivatives , SARS-CoV-2/physiology , Virus Internalization/drug effects , alpha-Cyclodextrins/pharmacology , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/metabolism , Binding Sites , COVID-19/pathology , COVID-19/prevention & control , COVID-19/virology , Computational Biology/methods , Humans , Membrane Microdomains/drug effects , Membrane Microdomains/metabolism , Membrane Microdomains/virology , Molecular Docking Simulation , Phenylethyl Alcohol/chemistry , Phenylethyl Alcohol/metabolism , Phenylethyl Alcohol/pharmacology , Phenylethyl Alcohol/therapeutic use , Protein Binding , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , alpha-Cyclodextrins/chemistry , alpha-Cyclodextrins/metabolism , alpha-Cyclodextrins/therapeutic use
17.
J Food Sci ; 86(9): 4026-4036, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34409609

ABSTRACT

Allicin, a chemical found in functional foods, has a variety of beneficial bioactivities but the unpleasent odor and unstability hinder its applications. Isolating products from cyclodextrin (CD) complexation, using ß-CD and its derivatives, is usually a time and energy-consuming process. Herein, a high-efficiency and eco-friendly preparation method of an inclusion (allicin@α-CD) formed by allicin and α-CD was designed, which turned liquid allicin into crystal particles with high-speed stirring (10,000 r/min) at 25°C for 10 min in water. In vivo and in vitro masking evaluations showed that the inclusion particles could decrease the unpleasant odor of allicin. Molecular docking and experimental characterization results illustrated that the main reason of odor masking was due to the disulfide and thiocarbonyl groups of allicin being partially encapsulated by the cavity of α-CD. Compared with the physical mixture, the stability of allicin in allicin@α-CD at 60°C for 10 days was 33-fold improved. Overall, this efficient strategy of inclusion provided a promising approach for the industrialization of allicin-related formulations. PRACTICAL APPLICATION: In this study, an environmentally friendly method of α-CD inclusion without the use of organic reagents was designed to solidify and stabilize allicin, which effectively masked the unpleasant odor and taste of allicin. It has contributed greatly to improving the compliance of consumers and provided a new and effective approach to broaden the application of allicin.


Subject(s)
Food Additives , Food Technology , Odorants , alpha-Cyclodextrins , Crystallization , Disulfides/chemistry , Food Additives/chemistry , Food Additives/standards , Food Technology/methods , Humans , Molecular Docking Simulation , Odorants/analysis , Solubility , Sulfinic Acids/chemistry , alpha-Cyclodextrins/chemistry
18.
Carbohydr Polym ; 263: 117993, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-33858580

ABSTRACT

For skin contact medical devices, realizing a strong contact with skin is essential to precisely detect human biological information and enable human-machine interaction. In this study, we aimed to fabricate and characterize an inclusion complex film (ICF) for skin adhesion using α-cyclodextrin (α-CD) and nonanyl group-modified PVA (C9-PVA) under wet conditions. Based on the water insolubility of C9-PVA and the inclusion ability of α-CD for alkyl groups, α-CD/C9-PVA ICF was prepared. Among the prepared ICFs, α-CD/2.5C9-PVA (w/w = 0.5) ICF showed the highest bonding strength and T-peeling strength to porcine skin. Furthermore, α-CD/2.5C9-PVA (w/w = 0.5) ICF had better water vapor transmission rate than that of commercial tapes. In addition, the ion permeability test revealed that α-CD/2.5C9-PVA (w/w = 0.5) ICF exhibited excellent Na and Cl ion permeability. These results demonstrated that the multi-functional α-CD/2.5C9-PVA (w/w = 0.5) ICF can be a promising adhesive for skin contact medical devices.


Subject(s)
Adhesives/chemistry , Polyvinyl Alcohol/chemistry , Skin , alpha-Cyclodextrins/chemistry , Adhesives/chemical synthesis , Animals , Ions/metabolism , Permeability , Platinum/chemistry , Polyvinyl Alcohol/analogs & derivatives , Polyvinyl Alcohol/chemical synthesis , Proteins/metabolism , Saline Solution/chemistry , Swine , Technology, Pharmaceutical/methods , Water/chemistry
19.
J Am Chem Soc ; 143(15): 5786-5792, 2021 04 21.
Article in English | MEDLINE | ID: mdl-33826331

ABSTRACT

Cyclodextrins (CDs) are doughnut-shaped cyclic oligosaccharides having a cavity and two rims. Inclusion binding in the cavity has long served as a classic model of molecular recognition, and rim binding has been neglected. We found that CDs recognize guests by size-sensitive binding using the two rims in addition to the cavity, using single-molecule electron microscopy and a library of graphitic cones as a solid-state substrate for complexation. For example, with its cavity and rim binding ability combined, γ-CD can recognize a guest of radius between 4 and 9 Å with a size-recognition precision of better than 1 Å, as shown by structural analysis of thousands of individual specimens and statistical analysis of the data thereof. A 2.5 ms resolution electron microscopic video provided direct evidence of the process of size recognition. The data suggest the occurrence of the rim binding mode for guests larger than the size of the CD cavity and illustrate a unique application of dynamic molecular electron microscopy for deciphering the spatiotemporal details of supramolecular events.


Subject(s)
Cyclodextrins/chemistry , Cyclodextrins/metabolism , Hydrophobic and Hydrophilic Interactions , Kinetics , Microscopy, Electron, Transmission , Nanotubes/chemistry , Particle Size , Thermodynamics , alpha-Cyclodextrins/chemistry , alpha-Cyclodextrins/metabolism , beta-Cyclodextrins/chemistry , beta-Cyclodextrins/metabolism , gamma-Cyclodextrins/chemistry , gamma-Cyclodextrins/metabolism
20.
Food Chem ; 356: 129639, 2021 Sep 15.
Article in English | MEDLINE | ID: mdl-33819789

ABSTRACT

In this work, the interaction between Kynurenic acid (KYNA) and several natural and modified cyclodextrins (CDs) is carried out. Among all the CD tested, HPß-CD showed the strongest complexation constant (KF), with a value of 270.94 ± 29.80 M-1. Between natural (α- and ß-) CDs, the complex of KYNA with ß-CD was the most efficient. The inclusion complex of KYNA with CDs showed a strong influence of pH and temperature. The KF value decreased at high pH values, when the pKa was passed. Moreover, an increase of the temperature caused a decrease in the KF values. The thermodynamic parameters of the complexation (ΔH°, ΔS° and ΔG°) were studied with negative entropy, enthalpy and spontaneity of the process at 25 °C. Moreover, the inclusion complex was also characterized using FTIR and TGA. Finally, molecular docking calculations provided different interactions and their influence in the complexation constant.


Subject(s)
Kynurenic Acid/chemistry , alpha-Cyclodextrins/chemistry , beta-Cyclodextrins/chemistry , Molecular Docking Simulation , Temperature , Thermodynamics
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