Water-soluble γ-cyclodextrin polymers with high molecular weight and their complex forming properties

γ-Cyclodextrin hydrogel for the sustained release of josamycin for potential ocular application

Glaucoma is the leading cause of blindness worldwide. However, its surgical treatment, in particular via trabeculectomy, can be complicated by fibrosis. In current clinical practice, application of the drug, Mitomycin C, prevents or delays fibrosis, but can lead to additional side effects, such as bleb leakage and hypotony. Previous in silico drug screening and in vitro testing has identified the known antibiotic, josamycin, as a possible alternative antifibrotic medication with potentially fewer side effects. However, a suitable ocular delivery mechanism for the hydrophobic drug to the surgical site does not yet exist. Therefore, the focus of this paper is the development of an implantable drug delivery system for sustained delivery of josamycin after glaucoma surgery based on crosslinked γ-cyclodextrin. γ-Cyclodextrin is a commonly used solubilizer which was shown to complex with josamycin, drastically increasing the drug's solubility in aqueous solutions. A simple γ-cyclodextrin crosslinking method produced biocompatible hydrogels well-suited for implantation. The crosslinked γ - cyclodextrin retained the ability to form complexes with josamycin, resulting in a 4-fold higher drug loading efficiency when compared to linear dextran hydrogels, and prolonged drug release over 4 days.

Appraisal terpenoids rich Boswellia carterri ethyl acetate extract in binary cyclodextrin oligomer nano complex for improving respiratory distress

Boswellia carterii (BC) resins plants have a long historical background as a treatment for inflammation, as indicated by information originating from multiple countries. Twenty-seven diterpenoids have been identified in ethyl acetate and total methanol BC, comprising seventeen boscartins of the cembrane-type diterpenoids and ten boscartols of the prenylaromadendrane-type diterpenoids. Moreover, twenty-one known triterpenoids have also been found, encompassing nine tirucallane-type, six ursane-type, four oleanane-type, and two lupane-type. The cembrane-type diterpenoids hold a significant position in pharmaceutical chemistry and related industries due to their captivating biological characteristics and promising pharmacological potentials. Extraction of BC, creation and assessment of nano sponges loaded with either B. carterii plant extract or DEX, are the subjects of our current investigation. With the use of ultrasound-assisted synthesis, nano sponges were produced. The entrapment efficiency (EE%) of medications in nano sponges was examined using spectrophotometry. Nano sponges were characterized using a number of methods. Within nano sponges, the EE% of medicines varied between 98.52 ± 0.07 and 99.64 ± 1.40%. The nano sponges' particle sizes varied from 105.9 ± 15.9 to 166.8 ± 26.3 nm. Drugs released from nano sponges using the Korsmeyer-Peppas concept. In respiratory distressed rats, the effects of BC plant extract, DEX salt and their nano formulations (D1, D5, P1 and P1), were tested. Treatment significantly reduced ICAM-1, LTB4, and ILβ 4 levels and improved histopathologic profiles, when compared to the positive control group. Boswellia extract and its nano sponge formulation P1 showed promising therapeutic effects. The effect of P1 may be due to synergism between both the extract and the formulation. This effect was achieved by blocking both ICAM-1 and LTB4 pathways, therefore counteracting the effects of talc powder.

Preparation and evaluation of a functional effervescent powder based on inclusion complexes of orange oil and β-cyclodextrin derivatives.. [DOI: 10.21203/rs.3.rs-2226110/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Flavoured functional effervescent powders are becoming increasingly popular by consumers due to their health benefits and easy dissolution. In present study, orange flavoured effervescent powders having functional properties were prepared. Orange oil (O) was blended with different essential oils (EOs) having high antioxidant activity. The orange oil and the O-EOs blends were subjected to gas chromatography-mass spectrometry (GC-MS) analysis and evaluation of radical scavenging activity. Combinations of two water soluble β-cyclodextrine polymers, 2-hydroxypropyl-β-cyclodextrine (2-HP-β-CD) and epihydrin-β-cyclodextrin (EPI-β-CD) were prepared at different molar ratios (3: 1 and 1: 3, F1 and F2, respectively). The O-EOs blends that showed the highest antioxidant activities and best odour qualities were encapsulated with F1 and F2, separately. The orange flavoured inclusion complexes were prepared by freeze drying method. The particle sizes of the inclusion complex powders were in the nanoscale. Characterization of the inclusion complexes nanoparticles were performed by scanning electron microscopy (SEM), Fourier transform infrared microscopy (FT-IR). The results confirmed the successful formation of the inclusion complexes. However, inclusion complex of O-EOs blend with F1 (O-F1C-IC) showed the smallest particle size (113.9 ± 15.9 nm), the more negative zeta potential (-27.1 ± 1.27 mV), the highest encapsulation efficiency (95.51%) and best odour quality. Therefore, it was mixed with an effervescent powder having high acceptable characteristics. The orange flavoured effervescent powder showed superior flowability.

Polycyclodextrins: Synthesis, functionalization, and applications

Cyclodextrins (CDs) are cyclic oligosaccharides with unique conical structure enabling host-guest inclusion complexes. However, virgin CDs sufferfrom low solubility, lack of functional groups and its inability to strong complexation with the guests. One of the most efficient ways to improve the properties of cyclodextrins is the synthesis of polycyclodextrins. Generally, there are two types of polycyclodextrins: 1) polymers containing CD units as parts of the main backbone; and 2) polymers with CD units as side chains. These polycyclodextrins are produced (i) from direct copolymerization of virgin cyclodextrins or cyclodextrins derivatives with various monomers including isocyanates, epoxides, carboxylic acids, anhydrides, acrylates, acrylamides and fluorinated aromatic compounds, or (ii) by post-functionalization of other polymers with CDs or CD derivatives.. By selecting the proper derivatives of CDs and controlling the polymerization, polycyclodextrins with linear, hyperbranched, and crosslinked structures have been synthesized. Polycyclodextrins have found significant applications in numerous areas, as adsorbents for removal of organic pollutants, carriers in gene/drug delivery, and for preparation of supramolecular based hydrogels. The focus of this review paper is placed on the synthesis, characterization, and applications of CDs so as to highlight challenges as well as the promising features of the future ahead of material developments based on CDs.

The classification and application of cyclodextrin polymers: a review

After introducing the concept of cyclodextrin polymers, their classification and applications have been summarized.

Synthesis and applications of sulfopropyl ether γ-cyclodextrin polymer as chiral selector in capillary electrophoresis

A novel sulfopropyl ether γ-cyclodextrin polymer (SPE-γ-CDP) through polycondensating sulfated cyclodextrins (SCDs) was synthesized. This synthesis approach also has the potential of preparing other derived cyclodextrins (CDs) polymers. The polymerized SCDs took on both the properties of SCDs and certain characteristics of polymers, such as chiral selectivity and high viscosity. Synthesis parameters, including reactions sequence, sulfation, and polycondensation conditions were investigated systematically. The product was characterized by elemental analysis, infrared spectroscopy (IR), and indirect UV detections prior to use as background electrolytes additive. The separation conditions, including the concentration of SPE-γ-CDP, the concentration and pH of running buffer, separation voltage, as well as the additional organic solution were optimized during chiral separation of neutral, acidic, and basic enantiomers in capillary electrophoresis (CE). SPE-γ-CDP was proven to be an effective chiral resolving agent in CE with the advantages of simple synthesis process, low cost, similar ratio of charge-to-mass, low current, great reproducibility, and reusability. Graphical Abstract Synthesis and applications of sulfopropyl ether γ-cyclodextrin polymer.

Supramolecular cyclodextrin-based drug nanocarriers

Supramolecular systems formed by the binding of several cyclodextrins (CDs) to polymers or lipids, either via non-covalent or covalent links, open a wide range of possibilities for the delivery of active substances. CDs can perform as multifunctionalizable cores to which very diverse (macro)molecules and drugs can be conjugated. Grafting with amphiphilic molecules can lead to nanoassemblies exhibiting a variety of architectures. CDs can also polymerize with other CDs or can be used to functionalize preexisting polymers to form polymers/networks with enhanced capability to form inclusion complexes. Alternatively, CDs can be exploited as transient cross-linkers to form poly(pseudo)rotaxane-based networks or zipper-like assemblies. Combination of mutifunctionality and complexation ability of CDs has been shown to be useful to develop depot-like formulations and colloidal nanocarriers with improved performances regarding easiness of administration, protection of the encapsulated substances, control of the delivery rate, and cell interactions. The aim of this review is to provide an overall view of the diversity of designs of CD-based supramolecular nanosystems with a special focus on the advances materialized in the last five years, including clinical trials.

Novel amino-cyclodextrin cross-linked oligomer as efficient carrier for anionic drugs: a spectroscopic and nanocalorimetric investigation

The amino groups of a novel oligomer of amino-cyclodextrins play a relevant role in the recognition process of diclofenac and this highlights the potential of short polymeric chains as new drug carriers.

Water-soluble inclusion complex of fullerene with γ-cyclodextrin polymer for photodynamic therapy

A method was developed to obtain a highly water-soluble C60–γ-CDP inclusion complex, which could efficiently generate ¹O₂ species with UVA irradiation.

Spectroscopic investigation on the inclusion complex formation between amisulpride and γ-cyclodextrin

The purpose of this research was to investigate inclusion complex formation between poorly soluble drug amisulpride (AMI) and γ-cyclodextrin (γ-CD). The solubility of AMI was enhanced by formation of inclusion complex of AMI with nano-hydrophobic cavity of γ-CD. The stoichiometry of inclusion complex was studied by continuous variation Job's plot method and found 1:1. The binding constant was found 1166.65 M(-1) by Benesi-Hildebrand plot. The molecular docking of AMI and γ-CD was done to investigate complexation. The inclusion complex formation was further confirmed by (1)H NMR and FT-IR, DSC and XRD analysis. The solubility of AMI was increased 3.74 times after inclusion complex formation with γ-CD.

Applications of isothermal titration calorimetry in pure and applied research--survey of the literature from 2010

Isothermal titration calorimetry (ITC) is a biophysical technique for measuring the formation and dissociation of molecular complexes and has become an invaluable tool in many branches of science from cell biology to food chemistry. By measuring the heat absorbed or released during bond formation, ITC provides accurate, rapid, and label-free measurement of the thermodynamics of molecular interactions. In this review, we survey the recent literature reporting the use of ITC and have highlighted a number of interesting studies that provide a flavour of the diverse systems to which ITC can be applied. These include measurements of protein-protein and protein-membrane interactions required for macromolecular assembly, analysis of enzyme kinetics, experimental validation of molecular dynamics simulations, and even in manufacturing applications such as food science. Some highlights include studies of the biological complex formed by Staphylococcus aureus enterotoxin C3 and the murine T-cell receptor, the mechanism of membrane association of the Parkinson's disease-associated protein α-synuclein, and the role of non-specific tannin-protein interactions in the quality of different beverages. Recent developments in automation are overcoming limitations on throughput imposed by previous manual procedures and promise to greatly extend usefulness of ITC in the future. We also attempt to impart some practical advice for getting the most out of ITC data for those researchers less familiar with the method.

Cyclodextrins and ternary complexes: technology to improve solubility of poorly soluble drugs

Cyclodextrins (CDs) are cyclic oligosaccharides composed of D-glucopyranoside units linked by glycosidic bonds. Their main property is the ability to modify the physicochemical and biological characteristics of low-soluble drugs through the formation of drug:CD inclusion complexes. Inclusion complexation requires that host molecules fit completely or partially within the CD cavity. This adjustment is directly related to the physicochemical properties of the guest and host molecules, easy accommodation of guest molecules within the CD cavity, stoichiometry, therapeutic dose, and toxicity. However, dosage forms may achieve a high volume, depending on the amount of CD required. Thus, it is necessary to increase solubilization efficiency in order to use smaller amounts of CD. This can be achieved by adding small amounts of water-soluble polymers to the system. This review addresses aspects related to drug complexation with CDs using water-soluble polymers to optimize the amount of CD used in the formulation in order to increase drug solubility and reduce dosage form volume.