Cyclodextrins: structure, physicochemical properties and pharmaceutical applications

Unravelling the interaction of ethyl cinnamate in 2-hydroxypropyl and methyl-β-cyclodextrin by spectroscopic and theoretical evaluation for enhanced antibacterial activities

Essential oil components are the most common agents used to inhibit pathogens. Ethyl cinnamate (ECIN) is a hydrophobic essential oil component with well-known antibacterial properties but is poorly soluble in water, which limits its applications. In this study, inclusion complexes (ICs) were prepared by encapsulating ECIN in β-cyclodextrin (βCD), 2-hydroxypropyl-βCD, or methyl-βCD using an ultrasonication method to enhance water solubility and thermal and antibacterial properties. UV-Vis absorption and fluorescence spectral results indicated strong non-covalent interactions between ECIN and βCD derivatives in aqueous solution, and double reciprocal profiles revealed a guest:host stoichiometry of 1:1. Fourier-transform infrared and proton nuclear magnetic resonance spectroscopy investigations revealed that the phenyl ring of ECIN is located deeply in the CD nanocavities. X-ray diffraction, ultraviolet-visible diffuse reflectance spectroscopy, photoluminescence, and field emission scanning electron microscopy were performed to obtain crystalline, optical, and morphological information on solid ECIN-CDs. Thermogravimetric/differential thermal studies confirmed the improved stability of ECIN in solid CD-ICs by detecting an increase in the degradation temperature of ECIN from 50-140 °C to 310-410 °C. Further, the geometrical and frontier molecular orbital structures of the ECIN-CDs were theoretically evaluated using parametric method-3. Finally, antibacterial assays conducted against the foodborne pathogens Staphylococcus aureus and Escherichia coli and revealed that encapsulated ECIN had a greater inhibitory effect, which suggested the devised nanocarriers promote the solubilization of essential oil components in aqueous solutions.

Cyclodextrin-based delivery systems for chemical and genetic drugs: Current status and future

Cyclodextrins (CDs) are cyclic polysaccharides characterized by their unique hollow structure, making them highly effective carriers for pharmaceutical agents. CD-based delivery systems are extensively utilized to enhance drug stability, increase solubility, improve oral bioavailability, and facilitate controlled release and targeted delivery. This review initially provides a concise overview of nano drug delivery systems, followed by a detailed introduction of the structural features and benefits of CDs. It further summarizes the applications of CD-based delivery systems and offers insights for the rational design of drug delivery systems. In this review, CD-based delivery systems are categorized into several types, such as covalently modified CD derivatives, non-modified CD inclusion complexes, poly-cyclodextrins and others. The application of CD-based systems for the delivery of genetic therapeutic agents and co-delivery of gene and drug is also presented. Finally, this review discusses potential challenges and opportunities that may arise in the future. With the development of nanotechnology and optimization of preparation process, CD-based drug delivery systems will provide a more effective, precise and safe approach to drug therapy.

Self-association of cyclodextrin inclusion complexes in a deep eutectic solvent enhances guest solubility

Cyclodextrins are widely used pharmaceutical excipients known to increase the solubility of drug compounds through formation of inclusion complexes. A prominent limitation of common cyclodextrins is their own scarce solubility in water, which renders them unsuitable for many drug formulations. Cyclodextrin solubility can be enhanced in appropriate media such as Deep Eutectic Solvents (DESs). However, DESs can also reduce the equilibrium constant for host-guest complexation, making it challenging to optimize drug solubility using cyclodextrin. To determine the impact and mechanism of cyclodextrin complexation in DES, we tracked changes in the solubility of methyl orange (MO), serving as a hardly soluble model compound, in the presence of β-cyclodextrin (CD) in hydrated urea-choline chloride DES. The highest achievable MO solubility is obtained in concentrated CD-in-DES mixtures at low hydration, resulting from the higher solubility of CD⊃MO complexes in DES compared to water as a solvent. Combining our results with molecular dynamics simulations, we provide evidence that CD⊃MO complexes self-associate into dimers and larger oligomers. This self-association of complexes greatly enhances MO solubilization by CD beyond that expected from the canonical 1:1 binding stoichiometry. This newly unraveled solubilization mechanism via cyclodextrins and its facilitation by DES should aid the design of future drug formulations.

Unlocking the potential of β-limit dextrin: Preparation, structure, properties, and promising applications

Starch is a widely used and economically important polymer; however, its industrial applications are limited by certain shortcomings, such as retrogradation and high digestion rate. To overcome these limitations, native starches can be hydrolyzed by β-amylase, resulting in the production of β-limit dextrin (β-LD) and maltose as a co-product. β-LD retains the original inner core structure of its parent amylopectin and contains truncated external chains that is not prone to form exterior chain helical. The described molecular structures of β-LD impart unique physicochemical attributes, including prevention of retrogradation, high solubility, relatively low digestibility, etc. Compared with other dextrins, β-LD has a more defined structure and a larger molecular weight, but it still maintains high solubility, which endows β-LD with a wider range of potential applications in food and pharmaceutical industries. The considerations for improving preparation efficiency of β-LD, identifying additional functional traits, and expanding its industrial applications have been outlined along with future research directions. The insights provided in this review will be advantageous for the commercial production and utilization of β-LD in food industry to create value from native starch.

Unveiling cyclodextrin conjugation as multidentate excipients: An exploratory journey across industries

The discovery of branched molecules like dextrin by Schardinger in 1903 marked the inception of cyclodextrin (CD) utilization, catalyzing its journey from laboratory experimentation to widespread commercialization within the pharmaceutical industry. CD, a cyclic oligosaccharide containing glucopyranose units, acts as a versatile guest molecule, forming inclusion complexes (ICs) with various host molecules. Computational studies have become instrumental in elucidating the intricate interactions between β-CD and guest molecules, enabling the prediction of binding energy, forces, affinity, and complex stability. The computational approach has established robust correlations with experimental outcomes, enhancing our understanding of CD-mediated complexation phenomena. This comprehensive review delves into the CD based Inclusion complex (CDIC) formation and a myriad of components, including drug molecules, amino acids, vitamins, and volatile oils. These complexes find applications across diverse industries, ranging from pharmaceuticals to nutraceuticals, food, fragrance, and beyond. In the pharmaceutical realm, β- CDICs offer innovative solutions for enhancing drug solubility, stability, and bioavailability, thus overcoming formulation challenges associated with poorly water-soluble drugs. Furthermore, the versatility of CDs extends beyond pharmaceuticals, with applications in the encapsulation of phytoactive compounds in nutraceuticals and the enhancing flavor, aroma in food and fragrance industries. This review underscores the pivotal role of CDs conjugation in modern drug delivery systems, emphasizing the importance of interdisciplinary approaches that integrate computational modeling with experimental validation. As the pharmaceutical landscape continues to evolve, CDs-based formulations stand poised to drive innovation and address the ever-growing demand for efficacious and patient-friendly drug delivery solutions.

Transglycosylation behavior of Mucor hiemalis endo-β-N-acetylglucosaminidase to β-cyclodextrin derivatives with multivalent glucose moieties for synthesizing cyclodextrin-based oligosaccharide clusters

We investigated the transglycosylation reaction of two types of oligosaccharide acceptors, i.e., β-cyclodextrin (CD) derivatives 1 and 2 conjugated with multiple glucose (Glc) units, catalyzed by endo-β-N-acetyl-glucosaminidase from Mucor hiemalis (Endo-M) using the oligosaccharide donor sialoglycopeptide (SGP). The acceptor specificity of the enzyme transglycosylation of 1 and 2 having seven Glc moieties within small nanoscale spatial regions on the β-CDs was investigated on the basis of the effect of the molar ratios of SGP to acceptors 1 or 2 with different spatial configurations on the transglycosylation behavior. The formation of the corresponding CD-based oligosaccharide clusters from Endo-M was also evaluated.

Native Cyclodextrin-Based Metal-Organic Frameworks (MOFs): Synthesis, Characterization, and Potential Applications in Food Industry

Metal-organic frameworks (MOFs) have become a highly usable system in various sectors because of their highly ordered structure and high porosity providing them with high storage capacity. However, their use is sometimes forbidden in the food industry due to the presence of some organic compounds which have undesirable effects. Cyclodextrins, which are considered GRAS (Generally Recognized as Safe) by the FDA, comes as a very good alternative to previously used compounds for the development of the MOFs to be used in the food packaging industry, especially in the packaging sector. The cyclodextrin MOF does possess edible, biocompatible, as well as biodegradable characteristics and due to these reasons, they have gained attention from researchers in the food industry. In this review, we focus on the recent advancements in the field of CD MOFs. We have emphasized the synthesis of these MOFs through different techniques, formations of their inclusion complex with bioactive compounds, and their characterization. Finally, we discussed the use of CD MOFs as carriers for various highly volatile bioactive compounds and their ability to increase the solubility and stability of these bioactive compounds.

Advanced Polymeric Nanoparticles for Cancer Immunotherapy: Materials Engineering, Immunotherapeutic Mechanism and Clinical Translation

Cancer immunotherapy, which leverages immune system components to treat malignancies, has emerged as a cornerstone of contemporary therapeutic strategies. Yet, critical concerns about the efficacy and safety of cancer immunotherapies remain formidable. Nanotechnology, especially polymeric nanoparticles (PNPs), offers unparalleled flexibility in manipulation-from the chemical composition and physical properties to the precision control of nanoassemblies. PNPs provide an optimal platform to amplify the potency and minimize systematic toxicity in a broad spectrum of immunotherapeutic modalities. In this comprehensive review, the basics of polymer chemistry, and state-of-the-art designs of PNPs from a physicochemical standpoint for cancer immunotherapy, encompassing therapeutic cancer vaccines, in situ vaccination, adoptive T-cell therapies, tumor-infiltrating immune cell-targeted therapies, therapeutic antibodies, and cytokine therapies are delineated. Each immunotherapy necessitates distinctively tailored design strategies in polymeric nanoplatforms. The extensive applications of PNPs, and investigation of their mechanisms of action for enhanced efficacy are particularly focused on. The safety profiles of PNPs and clinical research progress are discussed. Additionally, forthcoming developments and emergent trends of polymeric nano-immunotherapeutics poised to transform cancer treatment paradigms into clinics are explored.

Study on the impact of β-CD inclusion complex on the in vivo metabolism of ginsenoside Re: A pharmacokinetic, metabolite analysis, and tissue distribution investigation in a rat model

Triol-type ginsenoside Re (GS-Re) exhibits potent anti-myocardial ischemia-reperfusion effects, but its clinical use is hindered by poor bioavailability. This study evaluates the impact of β-cyclodextrin (β-CD) inclusion on GS-Re bioavailability and tissue dynamics in rat models. The GS-Re-β-CD complex was prepared using aqueous stirring and characterized. Male Wistar rats (200 ± 20 g) were administered GS-Re at a dose of 500 mg/kg. Plasma concentrations were quantified using UHPLC-MS/MS to evaluate pharmacokinetics and analyze metabolites in tissues and feces. Compared to the group receiving GS-Re alone, the GS-Re-β-CD inclusion complex exhibited significantly improved pharmacokinetic characteristics in rats: Maximum concentration (Cmax) increased by 1.86-fold. Area under the curve (AUC0-24 h) increased by 2.09-fold. Time to reach peak concentration (Tmax) was reduced, while the half-life (t1/2) was extended, suggesting a faster and prolonged absorption of GS-Re. Metabolite analysis showed higher concentrations of Rg1, Rg2, Rh1, F1, PPT, and Re in tissues with GS-Re-β-CD, while metabolite types remained unchanged. The inclusion of β-CD significantly enhanced the bioavailability and tissue concentration of GS-Re, as demonstrated by increased Cmax and AUC, along with a shorter Tmax and longer t1/2. These findings suggest that β-CD inclusion could be an effective strategy to improve the clinical applicability of GS-Re, providing valuable pharmacokinetic and tissue concentration insights for further development.

Inclusion Complex of Nimodipine with Sulfobutylether-β-cyclodextrin: Preparation, Characterization, In Vitro and In Vivo Evaluation

Nimodipine (NIMO) is used to treat ischemic nerve injury from subarachnoid hemorrhage (SAH), but its low aqueous solubility limits clinical safety and bioavailability. This study aims to improve NIMO's solubility by preparing inclusion complexes with sulfobutylether-β-cyclodextrin (SBE-β-CD), reducing the limitations of Nimotop® injection, including vascular irritation, toxicity, and poor dilution stability. The NIMO-SBE-β-CD inclusion complex (NIMO-CD) was characterized in both liquid and solid states through phase solubility studies and methods including DSC, FT-IR, XRD, and SEM. Dilution stability, hemolysis, vascular irritation, and acute toxicity tests were performed, with pharmacokinetic and pharmacodynamic studies using Nimotop® as the control. Physical characterization confirmed the successful formation of the inclusion complex. NIMO's solubility improved by 1202-fold (from 0.82 to 986.19 μg/mL at 25℃). NIMO-CD showed stability for 24 h when diluted, exhibited no hemolytic activity, reduced vascular irritation, and its median lethal dose (LD50) was 2.49 times higher than that of Nimotop®. Both NIMO-CD and Nimotop® displayed similar pharmacokinetic profiles. Behavioral assessments (mNSS scoring and CT), along with evaluations of hematoma area and histopathology, demonstrated that NIMO-CD significantly improved outcomes in intracerebral hemorrhage, greatly enhancing neurological recovery, reducing hematoma and edema, and achieving treatment effects comparable to those of Nimotop® injection. NIMO-CD significantly improves NIMO's solubility and stability while maintaining bioequivalence with Nimotop®. Furthermore, its enhanced safety profile indicates its potential as a superior formulation for treating ischemic nerve injuries.

Significantly improving the solubility and anti-inflammatory activity of fenofibric acid with native and methyl-substituted beta-cyclodextrins via complexation

The solubility of commonly used anti-inflammatory drugs has become a significant concern in contemporary medicine. Furthermore, inflammatory arthritis stands out as the most prevalent chronic inflammatory disease globally. The disease's pathology is characterized by heightened inflammation and oxidative stress, culminating in chronic pain and the loss of joint functionality. Fenofibric acid (FFA) exhibits notable anti-inflammatory potential. This research assesses the anti-inflammatory effects of FFA, both in its standalone form and as inclusion complexes (ICs) with β-cyclodextrin and its methyl derivatives. FFA is encapsulated within the cavities of cyclodextrins (CDs), a fact confirmed by spectral changes observed in FFA. Distinct rock and seed-like morphologies are apparent for FFA with CDs, indicating that the CDs have influenced the surface of the guest. The introduction of CDs significantly enhances the thermal stability of FFA. ICs demonstrate superior results in inflammation activity compared to FFA alone. The efficacy of FFA complexed with CDs in mitigating inflammation positions it as a promising new drug. Additionally, our findings reveal that incorporating FFA into the CD cavity as a drug release system enhances the pharmacological profile of this substance, FFA.

In silico drug encapsulation using 2-hydroxypropyl-β-CD, tyrosine kinase and tyrosinase inhibition of dinuclear Cu(II) carboxylate complexes

In recent years, copper carboxylate complexes have garnered significant interest for biological applications. This study focuses on 20 Cu(II) carboxylate complexes selected from our previous research. Due to the hydrophobic nature of these complexes, the 2-hydroxypropyl-β-cyclodextrin (2HPβCD) was employed as a carrier to reduce toxicity and increase solubility for controlling drug delivery. Monte Carlo calculations were performed to confirm the interaction between the optimized structures of Cu(II) complexes and 2HPβCD, forming a host-guest system. All the structures were simulated and optimized using DFT-D calculations in Material Studio 2017. The results indicated that a neutral medium is more favorable for the adsorption of these complexes into 2HPβCD. More negative binding energy values suggested strong and energetically favorable adsorption on 2HPβCD. Complexes 4, 5, and 7 exhibited the highest interaction, making them excellent candidates for drug delivery systems. DFT-D calculations were also used to investigate the release of complexes, revealing that complexes 5, 14, and 19 were difficult to release due to their lowest energy. In contrast, complexes 8, 9, and 16 were found to be most efficient to release due to weak non-covalent interactions with 2HPβCD as we can predict from binding energy obtained by DFT-D. No specific trend was observed in the interaction of the complexes with 2HPβCD. Additionally, the effects of these complexes on c-kit tyrosine kinase and Mushroom tyrosinase were studied by molecular docking. The results demonstrated that all the complexes interacted with the active site of respective receptors through hydrophobic interactions. Complexes containing 1,10-phenanthroline and 2,2-bipyrdine were identified as having a strong, spontaneous binding ability with receptors.

Anti-inflammatory effects of cyclodextrin nanoparticles enable macrophage repolarization and reduce inflammation

Inflammation plays a critical role in the pathophysiology of many diseases, and dysregulation of the involved signaling cascades often culminates in uncontrollable disease progression and, ultimately, chronic manifestation. Addressing these disorders requires balancing inflammation control while preserving essential immune functions. Cyclodextrins (CDs), particularly β-CD, have gained attention as biocompatible biomaterials with intrinsic anti-inflammatory properties, and chemical modification of their backbone offers a promising strategy to enhance their physicochemical properties, adaptability, and therapeutic potential. This study evaluated and characterized the immunomodulatory effects of amphiphilic CD derivatives, which self-assemble into nanoparticles, compared to soluble parent β-CD. In a human macrophage model, CD nanoparticles demonstrated superior anti-inflammatory activity, with derivative-specific effects tied to their physicochemical properties, surpassing the soluble β-CD control. Alongside the downregulation of key pro-inflammatory markers, significant reductions in inflammasome activation and changes in lipid profiles were observed. The findings of this study underscore the potential of cyclodextrin-based nanoparticles as versatile biomaterials for treating the complex pathophysiology of various acute and chronic inflammation-associated disorders.

β-Cyclodextrin and cucurbit[7]uril as protective encapsulation agents of the CO-releasing molecule [CpMo(CO)3Me]

The CO releasing ability of the complex [CpMo(CO)3Me] (1) (Cp = η5-C5H5) has been assessed using a deoxymyoglobin-carbonmonoxymyoglobin assay. In the dark, CO release was shown to be promoted by the reducing agent sodium dithionite in a concentration-dependent manner. At lower dithionite concentrations, where dithionite-induced CO release was minimised, irradiation at 365 nm with a low-power UV lamp resulted in a strongly enhanced release of CO (half-life (t1/2) = 6.3 min), thus establishing complex 1 as a photochemically activated CO-releasing molecule. To modify the CO release behaviour of the tricarbonyl complex, the possibility of obtaining inclusion complexes between 1 and β-cyclodextrin (βCD) or cucurbit[7]uril (CB7) by liquid-liquid interfacial precipitation (1@βCD(IP)), liquid antisolvent precipitation (1@CB7), and mechanochemical ball-milling (1@βCD(BM)) was evaluated. All these methods led to the isolation of a true inclusion compound (albeit mixed with nonincluded 1 for 1@βCD(BM)), as evidenced by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), FT-IR and FT-Raman spectroscopies, and 13C{1H} magic angle spinning (MAS) NMR. PXRD showed that 1@βCD(IP) was microcrystalline with a channel-type crystal packing structure. High resolution mass spectrometry studies revealed the formation of aqueous phase 1 : 1 complexes between 1 and CB7. For 1@βCD(IP) and 1@CB7, the protective effects of the hosts led to a decrease in the CO release rates with respect to nonincluded 1. βCD had the strongest effect, with a ca. 10-fold increase in t1/4 for dithionite-induced CO release, and a ca. 2-fold increase in t1/2 for photoinduced CO release.

The antitumor mechanisms of glabridin and drug delivery strategies for enhancing its bioavailability

Glabridin, a flavonoid derived from the plant Glycyrrhiza glabra, has garnered significant attention due to its diverse pharmacological effects, including antioxidant, antibacterial, anti-inflammatory, hypolipidemic, and hypoglycemic activities. Studies have shown that glabridin exhibits substantial antitumor activity by modulating the proliferation, apoptosis, metastasis, and invasion of cancer cells through the targeting of various signaling pathways, thus indicating its potential as a therapeutic agent for malignant tumors. To enhance its solubility, stability, and bioavailability, several drug delivery systems have been developed, including liposomes, cyclodextrin inclusion complexes, nanoparticles, and polymeric micelles. These de.livery systems have shown promise in preclinical studies but face challenges in clinical translation, such as issues with biocompatibility, delivery efficiency, and long-term stability. A comprehensive analysis of the antitumor mechanism of glabridin and its novel drug delivery system is still lacking. Therefore, the authors performed a comprehensive review of recent literature on the antitumor effects of glabridin and its novel drug delivery systems, covering the antitumor mechanism, action targets, and novel drug delivery systems, offering new theoretical insights and development directions for its further advancement and clinical application.

The application of cyclodextrins in drug solubilization and stabilization of nanoparticles for drug delivery and biomedical applications

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.

Poly(2-hydroxyethyl methacrylate-co-methacrylated hyaluronan-β-cyclodextrin) hydrogel: A potential contact lens material with high hydrophilicity, good mechanical properties and sustained drug delivery

A novel poly(2-hydroxyethyl methacrylate-co-methacrylated hyaluronan-β-cyclodextrin) [p(HEMA-co-mHA-β-CD)] hydrogel was developed as a potential contact lens for ophthalmic disease. The hydrogel was synthesized from the copolymerization of 2-hydroxyethyl methacrylate (HEMA) monomer and mHA-β-CD as a hydrophilic macromolecular crosslinker. By adjusting the methacrylate substitution degree in hyaluronan (20-29 %) and the mHA-β-CD content (5-11 %), transparent p(HEMA-co-mHA-β-CD) hydrogels were achieved. p(HEMA-co-m20HA-β-CD) hydrogels exhibited an enhanced tensile modulus (from 0.35 to 0.88 MPa) with a decreased elongation at break (from 255 % to 108 %), meanwhile they showed increased hydrophilicity with a decreased water contact angle (from 83.4° to 48.6°) and an increased equilibrium water content (from 38.2 % to 46.4 %). Increasing the mHA-β-CD content resulted in a higher encapsulation and cumulative release of hydrophilic levofloxacin hydrochloride or hydrophobic puerarin, due to the improved hydrophilicity and the formation of β-CD/drug inclusion complexes. Compared with pHEMA hydrogel, p(HEMA-co-m20HA-β-CD) hydrogels better inhibited the deposition of lysozyme and bovine serum albumin, and the bacterial adhesion against S. aureus and E. coli. The hydrogels were stable at physiological conditions and non-toxic to immortalized human keratinocytes. With good mechanical properties, tear protein deposition resistance, antibacterial activity, and sustained drug delivery capabilities, p(HEMA-co-m20HA-β-CD) hydrogels were identified as a promising contact lens material for eye diseases.

Evaluation of All-Atom and Martini 3 Coarse-Grained Force Fields from the Structural Investigation of Nitroxide Spin Probes and Their Confinement in Beta-Cyclodextrin

Nitroxide radicals have found wide applications as spin labels or probes, and their guest-host interactions with cyclodextrins exhibit enhanced applications in electron spin resonance (ESR) spectroscopy and imaging due to improved biostability toward reducing agents. Although the computational prediction of the guest-host binding has become increasingly common for small ligands, molecular simulations regarding the conformational preferences of hosted spin probes have not been conducted. Here we present molecular dynamics simulations at an atomistic level for a set of four TEMPO (2,2,6,6-tetramethylpiperidine 1-oxyl) spin probes and thereafter develop coarse-grained models compatible with the recent version of the Martini force field (v 3.0) to tackle their encapsulation in the cavity of β-cyclodextrin (βCD) for which experimental ESR data are available. The results indicate that the atomistic descriptions perform well in relation to the structural parameters derived from X-ray diffraction as well as hydrogen bonding and hydrogen patterns and predict that the guest-host complexation is hydrophobically driven by the presence of a methyl group pair of the spin probe at the cavity center of βCD. The spin probe mobility at the binding site reveals the nitroxide group orientation toward the secondary rim of the cyclodextrin and the alternating presence of the two methyl group pairs inside the cavity, features in agreement with the experimental behavior of the ESR parameters. The coarse-grained parameterizations of TEMPO probes and βCD rely on optimizing the bonded and nonbonded parameters with references to the atomistic simulation results, and they are capable of recovering the orientation and location of the spin probe inside the cyclodextrin cavity predicted by the atomistic guest-host complexes. The results suggest the cyclodextrin host-guest system as a powerful validation suite to evaluate new coarse-grained parameterizations of small ligands and future extensions to functionalized cyclodextrins in inclusion complexes.

Biopharmaceutical Characterization and Stability of Nabumetone-Cyclodextrins Complexes Prepared by Grinding

Background: Nabumetone (NAB) is a poorly soluble nonsteroidal anti-inflammatory prodrug (BCS class II drug) whose solubility is significantly improved by complexation with cyclodextrins (CDs). Methods: The solid complexes, in a 1:1 molar ratio, were prepared by mechanochemical activation by grinding, using β-cyclodextrin (β-CD) and its derivatives, hydroxypropyl- and sulfobutylether-β-cyclodextrin (HP-β-CD and SBE-β-CD). The complexation was confirmed by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and attenuated total reflectance Fourier-transformed infrared spectroscopy (ATR-FTIR). Obtained products were further characterized regarding their solubility, in vitro dissolution, permeability and chemical stability. Results: Co-grinding with HP-β-CD and SBE-β-CD yielded products that showed in vitro dissolution profiles in hydrochloric acid medium (pH 1.2) that were substantially different from that of pure NAB, yielding dissolution efficiency enhancements of 34.86 ± 1.64 and 58.30 ± 0.28 times, respectively, for the optimized products. Their in vitro dissolution and gastrointestinal permeability were also studied in a low-volume environment at pH 6.8, corresponding to the intestinal environment. Both β-CD derivatives increased NAB dissolution rate and NAB mass transport across the biomimetic membrane. The effect of β-CD derivatives on NAB chemical stability was studied under the stress conditions by the developed and validated UHPLC-DAD-HRMS method. In acidic conditions, pure and complexed NAB was prone to hydrolytic degradation, yielding one degradation product-pharmacologically inactive NAB metabolite. However, under the oxidative conditions at elevated temperatures, 10 NAB degradation products were identified from co-ground samples. All systems were stable during photo- and long-term stability studies. Conclusions: NAB complexes with HP-β-CD and SBE-β-CD are promising candidates for pharmaceutical product development.

The Role of Amphiphilic Compounds in Nasal Nanoparticles

Nasal medications hold significant importance and are widely utilized due to their numerous advantageous properties, offering a compelling route for both local and systemic therapeutic effects. Nowadays, the development of nasal particles under 1 micrometer is in the focus of much scientific research. In our experiments, the use of innovative nanotechnology to increase the effectiveness of the active substance was of paramount importance. Our aim was to create solid nanoparticles that enable targeted and effective delivery of the active ingredient into the body. The innovation of this experimental series lies not only in highlighting the importance of amphiphilic compounds in enhancing penetration, but also in the fact that while most nasally administered formulations are in liquid form, our formulation is solid. Liquid formulations frequently suffer from the disadvantage of possible leakage during administration, which can reduce the bioavailability of the active ingredient. In our experiments we created novel drug delivery systems of finely divided powders, which, thanks to the penetration enhancers, can be successfully administered. These enhancers facilitate the swift disintegration and penetration of the particles through the membrane. This represents a new direction in nasal drug delivery methods. The results of our trials are promising in the development of innovative pharmaceutical products and outline the role of amphiphilic compounds in more efficient utilization and targeted application of active substances. According to our results it can be concluded that this innovative approach not only addresses the common issues associated with liquid nasal formulations but also paves the way for more stable and effective delivery methods. The use of finely divided powders for nasal delivery, enabled by penetration enhancers, represents a major breakthrough in the field, providing a dependable alternative to conventional liquid formulations and ensuring improved therapeutic results.

Advancements in cyclodextrin-based controlled drug delivery: Insights into pharmacokinetic and pharmacodynamic profiles

This article discusses and summarizes some fascinating outcomes and applications of cyclodextrins (CDs) and their derivatives in drug delivery. These applications include the administration of protein, peptide medications, and gene delivery. Several innovative drug delivery systems, including NPs, microspheres, microcapsules, and liposomes, are designed with the help of CD, which is highlighted in this article. The use of these compounds as excipients in medicine formulation is reviewed, in addition to their well-known effects on drug solubility and dissolution, as well as their bioavailability, safety, and stability. Furthermore, the article focuses on many factors that influence the development of inclusion complexes, as having this information is necessary to manage these diverse materials effectively. An overview of the commercial availability, regulatory status, and patent status of CDs for pharmaceutical formulation is also presented. Due to the fact that CDs can discover new uses in drug delivery consistently, it is predicted that they will solve a wide range of issues related to the distribution of a variety of unique medications through various delivery channels.

Enhancing Cannabinoid Bioavailability in Pain Management: The Role of Cyclodextrins

Chronic pain (CP), including pain related to cancer, affects approximately 2 billion people worldwide, significantly diminishing quality of life and imposing socio-economic burdens. Current treatments often provide limited relief and may cause adverse effects, demanding more effective alternatives. Natural compounds from Cannabis sativa L., particularly cannabinoids like THC and CBD, exhibit analgesic and anti-inflammatory properties, but their therapeutic use is restricted by poor solubility and low bioavailability. Cyclodextrins (CDs) and cyclic oligosaccharides may encapsulate hydrophobic drugs in order to enhance their solubility and stability, offering a promising solution to these challenges. This study explores the formation of CD inclusion complexes with cannabinoids and specific terpenes, such as D-limonene (LIM), beta-caryophyllene (BCP), and gamma-terpinene (γ-TPN), aiming to improve pharmacokinetic profiles and therapeutic efficacy. We discuss analytical techniques for characterizing these complexes and their mechanisms of action, highlighting the potential of CDs to optimize drug formulations. The integration of CDs in cannabinoid therapies may enhance patient compliance and treatment outcomes in CP management. Future research should focus on innovative formulations and delivery systems to maximize the clinical applications of those compounds.

Microencapsulation techniques for developing cannabidiol formulations: a review

Cannabidiol (CBD), extracted from Cannabis sativa L., holds therapeutic promise without inducing psychoactive effects seen with Δ9-tetrahydrocannabinol. Its interaction with the endocannabinoid system plays a pivotal role in regulating mood, pain perception and immune function. Nevertheless, CBD encounters hurdles in clinical application due to its poor bioavailability and water solubility. To overcome these limitations, researchers are exploring microencapsulation techniques, which involve encapsulating CBD within protective matrices. This comprehensive review offers insights into various microencapsulation methods for CBD, scrutinizing their advantages, limitations and implications for formulation optimization. By elucidating the potential of microencapsulation, this review underscores its promise in refining CBD therapy and addressing challenges associated with administration.

Aqueous eye drop formulations: Cyclodextrins as enabling excipients

Cyclodextrins are enabling pharmaceutical excipients that solubilize and stabilize drugs in aqueous formulations. Cyclodextrins possess very favorable pharmacokinetic and toxicological profiles and are commonly used in marketed drug products for oral and parenteral administration. However, their use in ophthalmic products is still very limited. Cyclodextrins have a broad range of physical properties that are specifically appropriate for designing topical ophthalmic dosage forms. Additionally, both the regulatory and intellectual property environments have been cleared over the last years and should foster their use for designing new drugs for ophthalmic use.

Pharmaceutical approaches for enhancing solubility and oral bioavailability of poorly soluble drugs

High solubility in water and physiological fluids is an indispensable requirement for the pharmacological efficacy of an active pharmaceutical ingredient. Indeed, it is well established that pharmaceutical substances exhibiting limited solubility in water are inclined towards diminished and inconsistent absorption following oral administration, consequently resulting in variability in therapeutic outcomes. The current advancements in combinatorial chemistry and pharmaceutical design have facilitated the creation of drug candidates characterized by increased lipophilicity, elevated molecular size, and reduced aqueous solubility. Undoubtedly, the issue of poorly water-soluble medications has been progressively escalating over recent years. Indeed, 40% of the top 200 oral medications marketed in the United States, 33% of drugs listed in the US pharmacopoeia, 75% of compounds under development and 90% of new chemical entities are insufficiently water-soluble compounds. In order to address this obstacle, formulation scientists employ a variety of approaches, encompassing both physical and chemical methods such as prodrug synthesis, salt formation, solid dispersions formation, hydrotropic substances utilization, solubilizing agents incorporation, cosolvent addition, polymorphism exploration, cocrystal creation, cyclodextrins complexation, lipid formulations, particle size reduction and nanoformulation techniques. Despite the utilization of these diverse approaches, the primary reason for the failure in new drug development persists as the poor aqueous solubility of pharmaceutical compounds. This paper, therefore, delves into the foundational principles that underpin the implementation of various formulation strategies, along with a discussion on the respective advantages and drawbacks associated with each approach. Additionally, a discourse is provided regarding methodological frameworks for making informed decisions on selecting an appropriate formulation strategy to effectively tackle the key challenges posed during the development of a poorly water-soluble drug candidate.

Formulation and investigation of differently charged β-cyclodextrin-based meloxicam potassium containing nasal powders

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 β-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.

Pediatric Orally Disintegrating Tablets (ODTs) with Enhanced Palatability Based on Propranolol HCl Coground with Hydroxypropyl-β-Cyclodextrin

BACKGROUND

Propranolol, largely prescribed as an antihypertensive and antiarrhythmic drug in pediatrics, is characterized by a bitter taste and an astringent aftertaste. Currently, the therapy requires crushing of tablets for adults and their dispersion in water many times a day, leading to loss of dosing accuracy, low palatability, and poor compliance for both patients and caregivers.

OBJECTIVES

This work aimed to exploit cyclodextrin complexation by cogrinding to develop orally disintegrating tablets (ODTs) endowed with reliable dosing accuracy, good palatability and safety, ease of swallowability, and ultimately better compliance for both pediatric patients and caregivers.

RESULTS

Different formulation variables and process parameters were evaluated in preparing ODTs. The technological and morphological characterization and disintegration tests were performed according to official and alternative tests to select the ODT formulation based on the drug Hydroxypropyl-β-cyclodextrin (HPβCD) coground complex form containing Pearlitol® Flash as the diluent and 8% Explotab® as the superdisintegrant, which demonstrated the highest % drug dissolution in simulated saliva and acceptable in vitro palatability assessed by the electronic tongue, confirming the good taste-masking power of HPβCD towards propranolol.

CONCLUSIONS

Such a new dosage form of propranolol could represent a valid alternative to the common extemporaneous preparations, overcoming the lack of solid formulations of propranolol intended for pediatric use.

Fabrication of Uniform Melatonin Microparticles Potentially for Nasal Delivery: A Comparison of Spray Drying and Spray Freeze Drying

PURPOSE

Insomnia is a major health concern, and melatonin (MLT) is key for initiating sleep. Delivering MLT nasally can enhance brain bioavailability by targeting the olfactory region. This study aimed to fabricate MLT embedded microparticles for nasal delivery.

METHODS

MLT-cyclodextrin (CD) derivatives complex microparticles (MCCMPs) were fabricated by spray drying and spray freeze drying MLT and CD derivative solutions. Phase solubility and 1H-1H ROSEY NMR analysis assessed MLT-CD assembly. The effects of formulation compositions and process parameters on microparticle structural attributes were investigated. The in vitro nasal release and deposition performances were evaluated by a modified paddle-over-disk apparatus and 3D-printed nasal cavity cast, respectively.

RESULTS

Sodium sulphobutylether-β-cyclodextrin (SBE-β-CD) exhibited the best complexation ability with MLT, with the indole structure of MLT included in its cavity. Spray dried MCCMPs showed dense structure with high density, while the spray freeze dried counterpart showed the brittle and porous structure with low density. Despite the porous structure may promote the release rate of spray freeze dried samples, the high hydrophilicity of the CD derivative overshadows this advantage. Samples prepared by spray drying not only exhibited rapid release rates but also could deposit more effectively in the olfactory region, as they avoid breakage due to their higher mechanical strength. The optimal sample showed ~ 86.70% of the MLT released at 20 min and ~ 10.57% of the deposition fraction in the olfactory region.

CONCLUSIONS

This work compares MCCMPs fabricated by spray drying and spray freeze drying, providing the optimal formulation and process combinations.

Small Molecule Topical Ophthalmic Formulation Development-Data Driven Trends & Perspectives from Commercially Available Products in the US

Topical ophthalmic drug product development is a niche research domain as the drug formulations need to be designed to perform in the unique ocular physiological conditions. The most common array of small molecule drug formulations intended for topical ophthalmic administration include solutions, suspensions, emulsions, gels, and ointments. The formulation components such as excipients and container closure are unique to serve the needs of topical ophthalmic delivery compared to other parenteral products. The selection of appropriate formulation platform, excipients, and container closure for delivery of drugs by topical ophthalmic route is influenced by a combination of factors like physicochemical properties of the drug molecule, intended dose, pharmacological indication as well as the market trends influenced by the patient population. In this review, data from literature and packaging inserts of 118 reference listed topical ophthalmic medications marketed in the US are collected and analyzed to identify trends that would serve as a guidance for topical ophthalmic formulation development for small molecule drugs. Specifically, the topics reviewed include current landscape of the available small molecule topical ophthalmic drug products in the US, physicochemical properties of the active pharmaceutical ingredients (APIs), formulation platforms, excipients, and container closure systems.

Advances in carrier-delivered small interfering RNA based therapeutics for treatment of neurodegenerative diseases

Neurodegenerative diseases are devastating diseases that severely affect the health of people all over the world. RNA therapies have become one of the most promising critical drug treatments for neurodegenerative diseases due to their excellent gene and protein editing effects. However, the successful transport of RNA via the systemic route to the central nervous system remains one of the major obstacles in treating neurodegenerative diseases. This review will focus on therapeutic RNA that can successfully overcome the blood-brain barrier (BBB), with particular attention to small interfering RNAs (siRNAs), focusing on different types of neurodegenerative disease treatment strategies and accelerating their translation into clinical practice.

Review of Applications of β-Cyclodextrin as a Chiral Selector for Effective Enantioseparation

The significance and necessity of separating enantiomers in food, pharmaceuticals, pesticides, and other samples remains constant and unrelenting. The successful chiral separation usually includes the application of a chiral auxiliary compound, known also as a chiral selector (CS), that forms complexes with enantiomers of different physicochemical properties, enabling efficient separation. While both native and substituted cyclodextrins (CDs) are commonly used as CSs, β-CD is undoubtedly the most popular one among them. This review includes recent advancements in the application of β-CD as a CS. While the theoretical background behind the enantioseparation is also part of this work, the main emphasis is put on the factors that affect the efficacy of this process such as temperature, pH, solvent, and the choice of other additives. Also, the different analytical methods: Nuclear Magnetic Resonance (NMR) spectroscopy, Capillary Electrophoresis (CE), fluorescence spectroscopy (FS), High-Performance Liquid Chromatography (HPLC), Isothermal Titration Calorimetry (ITC), and UV-vis spectroscopy, used for enantioseparation with the aid of β-CD as CS, are thoroughly compared. Also, since some of the chiral compounds have been studied in the context of their enantioseparation more than once, those works are compared and critically analyzed. In conclusion, while β-CD can be in most cases used as CS, the choice of the experimental conditions and method of analysis is crucial to achieve the success.

New Conjugates of Hyaluronic Acid with γ-Cyclodextrin as Sorafenib Carrier in Cancer Cells

In recent years, nanoparticles based on cyclodextrins have been widely investigated, mainly for drug delivery. In this work, we synthesized nanoparticles with a hyaluronic acid backbone (11 kDa and 45 kDa) functionalized with γ-cyclodextrins. We tested sorafenib in the presence of the new hyaluronan-cyclodextrin conjugates in A2780 (ovarian cancer), SK-HeP-1 (adenocarcinoma) and MDA-MB-453 (breast cancer) cell lines. We found that hyaluronan-cyclodextrin conjugates improve the antiproliferative activity of sorafenib. Remarkably, the system based on the 11 kDa hyaluronan conjugate was the most effective and, in the MDA-MB-453 cell line, significantly reduced the IC50 value of sorafenib cells by about 75 %.

Recent developments in the encapsulation of lavender essential oil

The unregulated and extensive application of synthetic compounds, such as preservatives, pesticides, and drugs, poses serious concerns to the environment, food security, and global health. Essential oils (EOs) are valid alternatives to these synthetic chemicals due to their therapeutic, antioxidant, and antimicrobial activities. Lavender essential oil (LEO) can be potentially applied in food, cosmetic, textile, agricultural, and pharmaceutical industries. However, its bioactivity can be compromised by its poor stability and solubility, which severely restrict its industrial applications. Encapsulation techniques can improve the functionality of LEO and preserve its bioactivity during storage. This review reports recent advances in the encapsulation of LEO by different methods, such as liposomes, emulsification, spray drying, complex coacervation, inclusion complexation, and electrospinning. It also outlines the effects of different processing conditions and carriers on the stability, physicochemical properties, and release behavior of encapsulated LEO. Moreover, this review focuses on the applications of encapsulated LEO in different food and non-food products.

Risperidone-cyclodextrin complex reservoir combined with hydrogel-forming microneedle array patches for enhanced transdermal delivery

Hydrogel-forming microneedle array patches (HFMAPs) are microneedles that create microconduits upon insertion and swelling in the skin, potentially allowing prolonged drug delivery without generating sharps waste. Delivering hydrophobic drugs using HFMAPs poses challenges, which can be addressed using solubility enhancers such as cyclodextrins (CDs). This study aimed to deliver risperidone (RIS) transdermally using HFMAPs. To enhance the aqueous solubility of RIS hydroxypropyl-beta-cyclodextrin (HP-β-CD) and hydroxypropyl-gamma-cyclodextrin (HP-γ-CD) were utilised and their performance was tested using phase solubility studies. The aqueous solubility of RIS was enhanced by 4.75-fold and 2-fold using HP-β-CD and HP-γ-CD, respectively. RIS-HP-β-CD complex (CX) and physical mixture (PM) directly compressed tablets were prepared and combined with HFMAPs. Among the tested formulations, RIS-HP-β-CD PM reservoirs with 11 x 11 PVA/PVP HFMAPs exhibited the best performance in ex vivo studies and were further evaluated in in vivo experiments using female Sprague Dawley rats. The extended wear time of the MAPs resulted in the sustained release of RIS and its active metabolite 9-hydroxyrisperidone (9-OH-RIS) in plasma samples, lasting from 3 to 5 days with a 1-day application and up to 10 days with a 5-day application. For a 1-day application, HFMAPs showed greater systemic exposure to RIS compared to intramuscular control (AUC0-t: 13330.05 ± 2759.95 ng/mL/hour versus 2706 ± 1472 ng/mL/hour). Moreover, RIS exposure was extended to 5 days (AUC0-t: 12292.37 ± 1801.94 ng/mL/hour). In conclusion, HFMAPs could serve as an alternative for delivering RIS in a sustained manner, potentially improving the treatment of schizophrenia.

Cyclodextrin Complexes for the Treatment of Chagas Disease: A Literature Review

Cyclodextrins are ring-shaped sugars used as additives in medications to improve solubility, stability, and sensory characteristics. Despite being widespread, Chagas disease is neglected because of the limitations of available medications. This study aims to review the compounds used in the formation of inclusion complexes for the treatment of Chagas disease, analyzing the incorporated compounds and advancements in related studies. The databases consulted include Scielo, Scopus, ScienceDirect, PubMed, LILACS, and Embase. The keywords used were "cyclodextrin AND Chagas AND disease" and "cyclodextrin complex against Trypanosoma cruzi". Additionally, a statistical analysis of studies on Chagas disease over the last five years was conducted, highlighting the importance of research in this area. This review focused on articles that emphasize how cyclodextrins can improve the bioavailability, therapeutic action, toxicity, and solubility of medications. Initially, 380 articles were identified with the keyword "cyclodextrin AND Chagas disease"; 356 were excluded for not being directly related to the topic, using the keyword "cyclodextrin complex against Trypanosoma cruzi". Over the last five years, a total of 13,075 studies on Chagas disease treatment were found in our literature analysis. The studies also showed interest in molecules derived from natural products and vegetable oils. Research on cyclodextrins, particularly in the context of Chagas disease treatment, has advanced significantly, with studies highlighting the efficacy of molecules in cyclodextrin complexes and indicating promising advances in disease treatment.

Sculpturing the future of water-soluble cyclodextrin branched polymers in pharmaceutical applications

Water-soluble polymers of cyclodextrins (CyD) can be easily obtained in alkaline media following polycondensation of the naturally occurring monomers in the presence of a crosslinking agent. They can be further modified to customize specifically functionalized architectures. Compared to other macromolecules natural and not, the CyD polymers are endowed with a unique feature, the cone-shaped cavities where they can host guests of various nature. This element has sollicited interest in this class of molecules for a wide range of applications including the biomedical field, in particular drug delivery. The CyD polymers display excellent behavior in terms of water solubility and solubilizing power towards drugs and therapeutic agents that are incompatible with biological fluids. Moreover, they can load more than one type of therapeutic agent in a single system thus allowing to implement combination therapy. In spite of some very promising results as delivery systems, their potentialities remain limited by some intrinsic hurdles. Herein, we comment on their limits mainly related to the production process and the possible solutions to overcome them, giving an outlook on their assets for innovation in disease treatment.

Critical Review of Food Colloidal Delivery System for Bioactive Compounds: Physical Characterization and Application

Bioactive compounds (BACs) have attracted much attention due to their potential health benefits. However, such substances have problems such as difficulty dissolving in water, poor stability, and low intestinal absorption, leading to serious limitations in practical applications. Nowadays, food colloidal delivery carriers have become a highly promising solution due to their safety, controllability, and efficiency. The use of natural macromolecules to construct delivery carriers can not only regulate the solubility, stability, and intestinal absorption of BACs but also effectively enhance the nutritional added value of functional foods, improve sensory properties, and extend shelf life. Moreover, smart-responsive colloidal delivery carriers can control the release characteristics of BACs, thus improving their absorption rate in the human body. This review describes the characteristics of several typical food colloid delivery carriers, focuses on their physical properties from static structure to dynamic release, summarizes their applications in delivery systems, and provides an outlook on the future development of food colloid delivery carriers. The different compositions and structures of food colloids tend to affect their stability and release behaviors, and the different surface properties and rheological characteristics of the carriers predestine their different application scenarios. The control of in vivo release properties and the effect on food media should be emphasized in the future exploration of safer and more controllable carrier systems.

Purification of gamma-cyclodextrin via selective coordination with potassium ions to form metal-organic frameworks

Efficient purification of gamma-cyclodextrin (γ-CD) is always challenging due to its structural similarity to other CDs and low crystallinity in water. In addressing this issue, an approach was proposed based on the formation mechanism of cyclodextrin metal-organic frameworks (CD-MOFs). This method involved the selective coordination of CDs mixture with potassium ions in water, facilitated by ethanol-induced crystallization, leading to the purification of γ-CD. The results showed that potassium ions enhanced γ-CD crystallization, and ethanol was crucial to selectively coordinating potassium ions with γ-CD. The characterizations revealed that the resulting CD-MOFs exhibited a small particle size, high surface area, and high thermal stability, and was identical to γ-CD-MOF, further indicating the final γ-CD with high purity. The separation factors of γ-CD/α-CD and γ-CD/β-CD were 309 and 260, respectively. Moreover, this method was validated through its application to the industrial enzymatic CDs mixture. The purification of γ-CD could achieve 99.99 ± 0.01 % after four crystallization cycles. Therefore, selectively coordinating with potassium ions to form MOFs provided a valuable reference for the purification of γ-CD and even the direct synthesis of γ-CD-MOF from CDs mixture. This advancement will also benefit the future production and application of γ-CD.

Advances in Cyclodextrins and Their Derivatives in Nano-Delivery Systems

The diversity of cyclodextrins and their derivatives is increasing with continuous research. In addition to monomolecular cyclodextrins with different branched chains, cyclodextrin-based polymers have emerged. The aim of this review is to summarize these innovations, with a special focus on the study of applications of cyclodextrins and their derivatives in nano-delivery systems. The areas covered include nanospheres, nano-sponges, nanogels, cyclodextrin metal-organic frameworks, liposomes, and emulsions, providing a comprehensive and in-depth understanding of the design and development of nano-delivery systems.

Antidepressant-like and Beneficial Effects of a Neoponcirin-Beta-Cyclodextrin Inclusion Complex in Mice Exposed to Prolonged Stress

Neoponcirin causes anxiolytic-like effects in mice when administered intraperitoneally but not orally. Neoponcirin is non-water-soluble and insoluble in solvents, and in medium acid, it isomerizes, reducing its bioavailability. To improve the pharmacological properties of neoponcirin, we formed a neoponcirin complex with beta-cyclodextrin (NEO/βCD), which was characterized by FT-IR, UV-Vis, and NMR, and their solubility profile. We evaluated the antidepressant-like effects of NEO/βCD acutely administered to mice orally in the behavioral paradigms, the tail suspension (TST) and the forced swimming (FST) tests. We also analyzed the benefits of repeated oral doses of NEO/βCD on depression- and anxiety-like behaviors induced in mice by chronic unpredictable mild stress (CUMS), using the FST, hole board, and open field tests. We determined the stressed mice's expression of stress-related inflammatory cytokines (IL-1β, IL-6, and TNFα) and corticosterone. Results showed that a single or chronic oral administration of NEO/βCD caused a robust antidepressant-like effect without affecting the ambulatory activity. In mice under CUMS, NEO/βCD also produced anxiolytic-like effects and avoided increased corticosterone and IL-1β levels. The effects of the NEO/βCD complex were robust in both the acute and the stress chronic models, improving brain neurochemistry and recovering immune responses previously affected by prolonged stress.

Stimuli-responsive polymer-based nanosystems for cardiovascular disease theranostics

Stimulus-responsive polymers have found widespread use in biomedicine due to their ability to alter their own structure in response to various stimuli, including internal factors such as pH, reactive oxygen species (ROS), and enzymes, as well as external factors like light. In the context of atherosclerotic cardiovascular diseases (CVDs), stimulus-response polymers have been extensively employed for the preparation of smart nanocarriers that can deliver therapeutic and diagnostic drugs specifically to inflammatory lesions. Compared with traditional drug delivery systems, stimulus-responsive nanosystems offer higher sensitivity, greater versatility, wider applicability, and enhanced biosafety. Recent research has made significant contributions towards designing stimulus-responsive polymer nanosystems for CVDs diagnosis and treatment. This review summarizes recent advances in this field by classifying stimulus-responsive polymer nanocarriers according to different responsiveness types and describing numerous stimuli relevant to these materials. Additionally, we discuss various applications of stimulus-responsive polymer nanomaterials in CVDs theranostics. We hope that this review will provide valuable insights into optimizing the design of stimulus-response polymers for accelerating their clinical application in diagnosing and treating CVDs.

A review on revolutionizing ophthalmic therapy: Unveiling the potential of chitosan, hyaluronic acid, cellulose, cyclodextrin, and poloxamer in eye disease treatments

Ocular disorders, encompassing both common ailments like dry eye syndrome and more severe situations for instance age-related macular degeneration, present significant challenges to effective treatment due to the intricate architecture and physiological barriers of the eye. Polysaccharides are emerging as potential solutions for drug delivery to the eyes due to their compatibility with living organisms, natural biodegradability, and adhesive properties. In this review, we explore not only the recent advancements in polysaccharide-based technologies and their transformative potential in treating ocular illnesses, offering renewed optimism for both patients and professionals but also anatomy of the eye and the significant obstacles hindering drug transportation, followed by an investigation into various drug administration methods and their ability to overcome ocular-specific challenges. Our focus lies on biological adhesive polymers, including chitosan, hyaluronic acid, cellulose, cyclodextrin, and poloxamer, known for their adhesive characteristics enhancing drug retention on ocular surfaces and increasing bioavailability. A detailed analysis of material designs used in ophthalmic formulations, such as gels, lenses, eye drops, nanofibers, microneedles, microspheres, and nanoparticles, their advantages and limitations, the potential of formulations in improving therapeutic outcomes for various eye conditions. Moreover, we underscore the discovery of novel polysaccharides and their potential uses in ocular drug delivery.

Febuxostat ternary inclusion complex using SBE7-βCD in presence of a water-soluble polymer: physicochemical characterization, in vitro dissolution, and in vivo evaluation

Febuxostat (FBX), a potent xanthine oxidase inhibitor, is widely used as a blood uric acid-reducing agent and has recently shown a promising repurposing outcome as an anti-cancer. FBX is known for its poor water solubility, which is the main cause of its weak oral bioavailability. In a previous study, we developed a binary system complex between FBX and sulfobutylether-β-cyclodextrin (SBE7-βCD) with improved dissolution behavior. The aim of the current study was to investigate the effect of incorporating a water-soluble polymer with a binary system forming a ternary one, on further enhancement of FBX solubility and dissolution rate. In vivo oral bioavailability was also studied using LC-MS/MS chromatography. The polymer screening study revealed a marked increment in the solubility of FBX with SBE7-βCD in the presence of 5% w/v polyethylene glycol (PEG 6000). In vitro release profile showed a significant increase in the dissolution rate of FBX from FBX ternary complex (FTC). Oral in vivo bioavailability of prepared FTC showed more than threefold enhancement in Cmax value (17.05 ± 2.6 µg/mL) compared to pure FBX Cmax value (5.013 ± 0.417 µg/mL) with 257% rise in bioavailability. In conclusion, the association of water-soluble polymers with FBX and SBE7-βCD system could significantly improve therapeutic applications of the drug.

Design and development of a chitosan-based nasal powder of dimethyl fumarate-cyclodextrin binary systems aimed at nose-to-brain administration. A stability study

The nasal administration route has been studied for the delivery of active molecules directed to the Central Nervous System, thanks to the anatomical connection between the nasal cavity and the brain. Dimethyl fumarate is used to treat relapsing-remitting multiple sclerosis, with a role as an immunomodulator towards T- T-cells and a cytoprotector towards neurons and glial cells. Its use in therapy is hindered by its low aqueous solubility, and low stability, due to hydrolysis and sublimation at room temperature. To overcome this limitation, in this study we evaluated the feasibility of using two amorphous β-cyclodextrin derivatives, namely hydroxypropyl β-cyclodextrin and methyl β-cyclodextrin, to obtain a nasally administrable powder with a view to nose-to-brain administration. Initially, the interaction product was studied using different analytical methods (differential scanning calorimetry, Fourier transform infrared spectroscopy and powder X-ray diffraction) to detect the occurrence of binary product formation, while phase solubility analysis was used to probe the complexation in solution. The dimethyl fumarate-cyclodextrin binary product showing best solubility and stability properties was subsequently used in the development of a chitosan-based mucoadhesive nasally administrable powder comparing different preparative methods. The best performance in terms of both hydrolytic stability and DMF recovery was achieved by the powder obtained via freeze-drying.

Supersaturated Drug Delivery System of Oxyberberine Based on Cyclodextrin Nanoaggregates: Preparation, Characterization, and in vivo Application

Propose

Oxyberberine (OBB), one of the main metabolites of berberine derived from intestinal and erythrocyte metabolism, exhibits appreciable anti-hyperuricemic activity. However, the low water solubility and poor plasma concentration-effect relationship of OBB hamper its development and utilization. Therefore, an OBB-hydroxypropyl-β-cyclodextrin (HP-β-CD) supersaturated drug delivery system (SDDS) was prepared and characterized in this work.

Methods

OBB-HP-β-CD SDDS was prepared using the ultrasonic-solvent evaporation method and characterized. Additionally, the in vitro and in vivo release experiments were conducted to assess the release kinetics of OBB-HP-β-CD SDDS. Subsequently, the therapeutic efficacy of OBB-HP-β-CD SDDS on hyperuricemia (HUA) was investigated by means of histopathological examination and evaluation of relevant biomarkers.

Results

The results of FT-IR, DSC, PXRD, NMR and molecular modeling showed that the crystallized form of OBB was transformed into an amorphous OBB-HP-β-CD complex. Dynamic light scattering indicated that this system was relatively stable and maintained by formation of nanoaggregates with an average diameter of 23 nm. The dissolution rate of OBB-HP-β-CD SDDS was about 5 times higher than that of OBB raw material. Furthermore, the AUC0-t of OBB-HP-β-CD SDDS (10.882 μg/mL*h) was significantly higher than that of the raw OBB counterpart (0.701 μg/mL*h). The oral relative bioavailability of OBB-HP-β-CD SDDS was also enhanced by 16 times compared to that of the raw material. Finally, in vivo pharmacodynamic assay showed the anti-hyperuricemic potency of OBB-HP-β-CD SDDS was approximately 5-10 times higher than that of OBB raw material.

Conclusion

Based on our findings above, OBB-HP-β-CD SDDS proved to be an excellent drug delivery system for increasing the solubility, dissolution, bioavailability, and anti-hyperuricemic potency of OBB.

Supramolecular deep eutectic solvent: a powerful tool for pre-concentration of trace metals in edible oil

The utilization of supramolecular deep eutectic solvent eddy-assisted liquid-liquid microextraction utilizing 2-hydroxypropyl β-cyclodextrin (SUPRADES) has been identified as a successful method for pre-enriching Cu, Zn, and Mn in vegetable oil samples. Determination of each element was conducted by inductively coupled plasma optical emission spectrometry (ICP-OES) after digestion of metal-enriched phases. Various parameters were examined, including the composition of SUPRADES species [2HP-β-CD: DL-lactic acid], a cyclodextrin mass ratio of 20 wt%, a water bath temperature of 75 °C, an extractor volume of 800 μL, a dispersant volume of 50 μL, and an eddy current time of 5 min. Optimal conditions resulted in extraction rates of 99.6% for Cu, 105.2% for Zn, and 101.5% for Mn. The method exhibits a broad linear range spanning from 10 to 20,000 μg L-1, with determination coefficients exceeding 0.99 for all analytes. Enrichment coefficients of 24, 21, and 35 were observed. Limits of detection ranged from 0.89 to 1.30 μg L-1, while limits of quantification ranged from 3.23 to 4.29 μg L-1. The unique structural characteristics of the method enable the successful determination of trace elements in a variety of edible vegetable oils.

Inclusion complexes of β-cyclodextrin with isomeric ester aroma compounds: Preparation, characterization, mechanism study, and controlled release

Cyclodextrins (CDs) have been discovered to provide an efficient solution to the limited application of ester aroma molecules used in food, tobacco, and medication due to their strong smell and unstable storage. This work combined molecular modeling and experimental to analyze the conformation and controlled release of isomeric ester aroma compounds/β-CD inclusion complexes (ICs). The investigation revealed that ester aroma compounds could be effectively encapsulated within the β-CD cavity, forming ICs with low binding affinity. Furthermore, the key driving forces in ICs were identified as hydrogen bonds and van der Waals interactions through theoretical simulation. Results from the Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) and Isothermal titration calorimetry (ITC) experiments confirmed the intermolecular interaction predicted by the molecular model. Notably, the release rate of aroma compounds from L-menthyl acetate/β-CD (LMA/β-CD) IC exceeded that of terpinyl acetate/β-CD (TA/β-CD) IC. This difference is attributed to the length of the chain of aroma molecules and the variation in the position of functional groups, influencing the stable formation of ICs with β-CD. These findings hold potential implications for refining the application of ICs across diverse industries.