Diversity of β-cyclodextrin-based nanosponges for transformation of actives

Controlled Release of the Anticancer Drug Cyclophosphamide from a Superparamagnetic β-Cyclodextrin Nanosponge by Local Hyperthermia Generated by an Alternating Magnetic Field

A β-cyclodextrin (β-CD) nanosponge (NS) was synthesized using diphenyl carbonate (DPC) as a cross-linker to encapsulate the antitumor drug cyclophosphamide (CYC), thus obtaining the NSs-CYC system. The formulation was then associated with magnetite nanoparticles (MNPs) to develop the MNPs-NSs-CYC ternary system. The formulations mentioned above were characterized to confirm the deposition of the MNPs onto the organic matrix and that the superparamagnetic nature of the MNPs was preserved upon association. The association of the MNPs with the NSs-drug complex was confirmed through field emission scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, dynamic light scattering, ζ-potential, atomic absorption spectroscopy, X-ray powder diffraction, selected area electron diffraction, and vibrating-sample magnetometer. The superparamagnetic properties of the ternary system allowed the release of CYC by utilizing magnetic hyperthermia upon the exposure of an alternating magnetic field (AMF). The drug release experiments were carried out at different frequencies and intensities of the magnetic field, complying with the "Atkinson-Brezovich criterion". The assays in AMF showed the feasibility of release by controlling hyperthermia of the drug, finding that the most efficient conditions were F = 280 kHz, H = 15 mT, and a concentration of MNPs of 5 mg/mL. CYC release was temperature-dependent, facilitated by local heat generation through magnetic hyperthermia. This phenomenon was confirmed by DFT calculations. Furthermore, the ternary systems outperformed the formulations without MNPs regarding the amount of released drug. The MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assays demonstrated that including CYC within the magnetic NS cavities reduced the effects on mitochondrial activity compared to those observed with the free drug. Finally, the magnetic hyperthermia assays showed that the tertiary system allows the generation of apoptosis in HeLa cells, demonstrating that the MNPs embedded maintain their properties to generate hyperthermia. These results suggest that using NSs associated with MNPs could be a potential tool for a controlled drug delivery in tumor therapy since the materials are efficient and potentially nontoxic.

Cyclodextrin Inclusion Complexes for Improved Drug Bioavailability and Activity: Synthetic and Analytical Aspects

Many active pharmaceutical ingredients show low oral bioavailability due to factors such as poor solubility and physical and chemical instability. The formation of inclusion complexes with cyclodextrins, as well as cyclodextrin-based polymers, nanosponges, and nanofibers, is a valuable tool to improve the oral bioavailability of many drugs. The microencapsulation process modifies key properties of the included drugs including volatility, dissolution rate, bioavailability, and bioactivity. In this context, we present relevant examples of the stabilization of labile drugs through the encapsulation in cyclodextrins. The formation of inclusion complexes with drugs belonging to class IV in the biopharmaceutical classification system as an effective solution to increase their bioavailability is also discussed. The stabilization and improvement in nutraceuticals used as food supplements, which often have low intestinal absorption due to their poor solubility, is also considered. Cyclodextrin-based nanofibers, which are polymer-free and can be generated using environmentally friendly technologies, lead to dramatic bioavailability enhancements. The synthesis of chemically modified cyclodextrins, polymers, and nanosponges based on cyclodextrins is discussed. Analytical techniques that allow the characterization and verification of the formation of true inclusion complexes are also considered, taking into account the differences in the procedures for the formation of inclusion complexes in solution and in the solid state.

Enhancement in the therapeutic potential of Lapatinib ditosylate against breast cancer by the use of β-cyclodextrin based ternary nanosponge system

The present investigation was performed to demonstrate the therapeutic potential of lapatinib ditosylate (LD) loaded nanosponge for the treatment of breast cancer. The study reports the fabrication of nanosponge by reaction of β-cyclodextrin with a cross-linking agent, diphenyl carbonate, at several molar ratios using the ultrasound-assisted synthesis method. The drug was loaded into the rightest nanosponge by lyophilization with and without 0.25% w/w polyvinylpyrrolidone. The significantly reduced crystallinity of developed formulations was established by differential scanning calorimetry (DSC), and powder X-ray diffractometry (PXRD). Morphological changes of LD, and formulations were compared by scanning electron microscopic (SEM) technique. Fourier transform infrared (FT-IR), and nuclear magnetic resonance (NMR) spectroscopic analysis were performed to establish the interacting groups of the host and guest molecules. It revealed interaction of the quinazoline ring, furan ring, and chlorobenzene functionality of LD with the hydroxyl group of β-cyclodextrin based nanosponge. Similar predictions were also obtained during their in-silico analysis. Saturation solubility and in vitro drug release studies revealed a 4.03-fold, and 2.43-fold rise in aqueous solubility, and dissolution of LD in the optimized formula (F2). The MCF-7 cell line study, too, revealed the higher efficiency of nanosponge formulations. The in vivo pharmacokinetic studies of optimized formulation illustrated 2.76-times, and 3.34-times enhancements in C_max and oral bioavailability, respectively. Concomitant results were obtained during the in vivo studies performed using DMBA-induced breast cancer models in female Sprague Dawley rats. The tumor burden was found to be reduced to approximately 60% by the use of F2. The hematological parameters of animals treated with F2 were also improved. Histopathology of breast tissue excised from an F2-treated rat showed a reduced size of ductal epithelial cells associated with shrunken cribriform structures and cross-bridges. The in vivo toxicity studies also showcased reduced hepatotoxicity of the formulation. Altogether, it can be concluded that encapsulation of lapatinib ditosylate in β-cyclodextrin nanosponge has improved aqueous solubility, bioavailability and, in turn, therapeutic efficacy.

Targeted Fisetin-Encapsulated β-Cyclodextrin Nanosponges for Breast Cancer

Fisetin (FS) is considered a safer phytomedicine alternative to conventional chemotherapeutics for breast cancer treatment. Despite its surpassing therapeutic potential, its clinical utility is hampered by its low systemic bioavailability. Accordingly, as far as we are aware, this is the first study to develop lactoferrin-coated FS-loaded β-cyclodextrin nanosponges (LF-FS-NS) for targeted FS delivery to breast cancer. NS formation through cross-linking of β-cyclodextrin by diphenyl carbonate was confirmed by FTIR and XRD. The selected LF-FS-NS showed good colloidal properties (size 52.7 ± 7.2 nm, PDI < 0.3, and ζ-potential 24 mV), high loading efficiency (96 ± 0.3%), and sustained drug release of 26 % after 24 h. Morphological examination using SEM revealed the mesoporous spherical structure of the prepared nanosponges with a pore diameter of ~30 nm, which was further confirmed by surface area measurement. Additionally, LF-FS-NS enhanced FS oral and IP bioavailability (2.5- and 3.2-fold, respectively) compared to FS suspension in rats. Antitumor efficacy evaluation in vitro on MDA-MB-231 cells and in vivo on an Ehrlich ascites mouse model demonstrated significantly higher activity and targetability of LF-FS-NS (30 mg/kg) compared to the free drug and uncoated formulation. Consequently, LF-FS-NS could be addressed as a promising formulation for the effective management of breast cancer.

Hairy Nanocellulose-Based Supramolecular Architectures for Sustained Drug Release

The engineering of a new type of trifunctional biopolymer-based nanosponges polymerized by cross-linking beta-cyclodextrin ethylene diamine (βCD-EDA) with bifunctional hairy nanocellulose (BHNC) is reported herein. We refer to the highly cross-linked polymerized BHNC-βCD-EDA network as BBE. βCD-EDA and BHNC were cross-linked at various ratios with the help of DMTMM (4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium) as a green activator in deionized water as a solvent, which resulted in different morphological shapes of BBE. Some of these structures were chiral due to cross-linked liquid crystalline structures. A comprehensive characterization study was done to show their unique morphological, structural, and dimensional properties of BBEs. Moreover, to further investigate and to confirm the surface modification of the precursors and final BBE structures, Fourier transform infrared and nuclear magnetic resonance spectroscopy, thermogravimetric analysis, Brunauer-Emmett-Teller analysis, and X-ray diffraction were applied. The hairy nanocellulose particles were considered as the backbone, and the immobilized cyclodextrin cavities can capture doxorubicin, which was used as a model drug molecule via host-guest inclusion complexation. Finally, the obtained BBE networks showed different and sustained drug release profiles and pH responsiveness. BBE biopolymers were tested as biocompatible nanocarriers for controlled release. We realize that these structures are too big for anti-cancer drug delivery by injection or oral intake, but these structures have a high potential to be applied in wound dressing and implants. They could also be used for capturing antibiotics, dyes, and organic compounds from wastewater.

Ensembles of carboxymethyl cyclodextrins on cationic liposomes as highly efficient nanocontainers for the delivery of hydrophobic compounds

The increase of payload is one of the key tasks in creation of nanocontainers for the delivery of bioactive substances (BAS). In this work the adsorption of anionic carboxymethyl cyclodextrins (CMCDs) on the surface of cationic liposomes was studied as mechanism of formation of capacious nanocontainers for the encapsulation and delivery of hydrophobic BAS. The formation and physico-chemical characteristics of complexes were studied by means of laser microelectrophoresis, dynamic light-scattering, conductometry and atomic force microscopy (AFM). As a model, bioactive molecule hydrophobic curcumin was chosen for the investigation. The encapsulation of curcumin was controlled by UV-Vis spectrometry. Interaction of CMCDs/liposomes complexes with model cell membranes was visualized by fluorescent microscopy. Finally, cytotoxicity of nanocontainers was studied by MTT-test. It was estimated that colloid stable complexes with net positive charge could contain up to 2.5÷5 CMCD molecules per one cationic lipid. Incorporation of curcumin in CMCDs does not change the character of interaction of oligosaccharides with liposomal membranes of individual liposome. CMCDs/liposomes complexes adsorb on model cell membranes without significant loss of CMCD molecules. This fact in addition to low cytotoxicity of cationic CMCDs/liposomes complexes demonstrates potential of their application as nanovehicles for the delivery of BAS.

Developing New Cyclodextrin-Based Nanosponges Complexes to Improve Vitamin D Absorption in an In Vitro Study

Vitamin D plays an important role in numerous cellular functions due to the ability to bind the Vitamin D receptor (VDR), which is present in different tissues. Several human diseases depend on low vitamin D3 (human isoform) serum level, and supplementation is necessary. However, vitamin D3 has poor bioavailability, and several strategies are tested to increase its absorption. In this work, the complexation of vitamin D3 in Cyclodextrin-based nanosponge (CD-NS, in particular, βNS-CDI 1:4) was carried out to study the possible enhancement of bioactivity. The βNS-CDI 1:4 was synthesized by mechanochemistry, and the complex was confirmed using FTIR-ATR and TGA. TGA demonstrated higher thermostability of the complexed form. Subsequently, in vitro experiments were performed to evaluate the biological activity of Vitamin D3 complexed in the nanosponges on intestinal cells and assess its bioavailability without cytotoxic effect. The Vitamin D3 complexes enhance cellular activity at the intestinal level and improve its bioavailability. In conclusion, this study demonstrates for the first time the ability of CD-NS complexes to improve the chemical and biological function of Vitamin D3.

Chitosan bead containing metal-organic framework encapsulated heteropolyacid as an efficient catalyst for cascade condensation reaction

Using cyclodextrin and chitosan that are bio-based compounds, a novel bi-functional catalytic composite is designed, in which metal-organic framework encapsulated phosphomolybdic acid was incorporated in a dual chitosan-cyclodextrin nanosponge bead. The composite was characterized via XRD, TGA, ICP, BET, NH₃-TPD, FTIR, FE-SEM/EDS, elemental mapping analysis and its catalytic activity was examined in alcohol oxidation and cascade alcohol oxidation-Knoevenagel condensation reaction. It was found that the designed catalyst that possess both acidic feature and redox potential could promote both reactions in aqueous media at 55 °C and various substrates with different electronic features could tolerate the aforementioned reactions to furnish the products in 75-95% yield. Furthermore, the catalyst could be readily recovered and recycled for five runs with slight loss of the catalytic activity. Notably, in this composite the synergism between the components led to high catalytic activity, which was superior to each component. In fact, the amino groups on the chitosan served as catalysts, while cyclodextrin nanosponge mainly acted as a phase transfer agent. Moreover, measurement of phosphomolybdic acid leaching showed that its incorporation in metal-organic framework and bead structure could suppress its leaching, which is considered a drawback for this compound. Other merits of this bi-functional catalyst were its simplicity, use of bio-based compounds and true catalysis, which was proved via hot filtration.

Encapsulation of Benzyl Isothiocyanate with β-Cyclodextrin Using Ultrasonication: Preparation, Characterization, and Antibacterial Assay

Benzyl isothiocyanate (BITC) is widely utilized in multiple biomedical fields, due to its significant antibacterial properties and low toxicity. However, poor water solubility and pungent odor has limited its application in the food industry. In this study, we first prepared inclusion complexes of BITC in GLU-β-CD and HP-β-CD using ultrasound, which is able to overcome the hindrance of poor water solubility and high volatility. Then, the BITC-β-CD inclusion complexes were characterized by using high-performance liquid chromatography (HPLC), nuclear magnetic resonance hydrogen spectra (¹H-NMR), infrared absorption spectra (IR), and differential scanning calorimetry (DSC) to confirm their stability. Further, the evaluation of antibacterial and antitumor effects of the BITC-β-CD inclusion complexes showed that they had great bactericidal activity against both Escherichia coli and Staphylococcus aureus cells, and also inhibited the growth of HepG2 cells in vitro. In addition, our results indicated that BITC-β-CD complexes were able to inhibit the growth of S. aureus in broccoli juice and extend the shelf life of broccoli juice, demonstrating the potential of β-cyclodextrin to improve the stability and controlled release of BITC. Taken together, our results show that BITC-β-CD complexes have good potential for application in the food industry.

Nanomolar detection of food additive tert-butylhydroquinone in edible oils based on novel ternary metal oxide embedded β-cyclodextrin functionalized carbon black

It is pivotal to precisely detect food preservatives to ascertain food quality and safety. In this work, we report the sensitive electrochemical detection of widely used cytotoxic food preservative tert-butylhydroquinone (TBHQ). A novel nanocomposite was sonochemically prepared by embedding ternary metal oxide (TMO) comprising ZnO, CuO, and MgO in β-cyclodextrin (β-CD) functionalized carbon black (CB). The properties of the prepared nanocomposite were evaluated by employing multiple characterization methods. The nanocomposite fabricated on a screen printed carbon electrode exhibited exceptional electrocatalytic activity towards TBHQ detection, evident from the resultant very low detection limit of 1 nM and high sensitivity of 22.67 μA μM^-1 cm^-2. Moreover, the developed TBHQ sensor evinced all the important traits of a good electrochemical sensor including excellent selectivity, stability, reproducibility, and repeatability. Furthermore, for validating practical feasibility of TBHQ detection, we successfully determined this food additive in edible oils.

Cyclodextrin-Based Nanosponges: Overview and Opportunities

Nanosponges are solid cross-linked polymeric nano-sized porous structures. This broad concept involves, among others, metal organic frameworks and hydrogels. The focus of this manuscript is on cyclodextrin-based nanosponges. Cyclodextrins are cyclic oligomers of glucose derived from starch. The combined external hydrophilicity with the internal hydrophobic surface constitute a unique “microenvironment”, that confers cyclodextrins the peculiar ability to form inclusion host‒guest complexes with many hydrophobic substances. These complexes may impart beneficial modifications of the properties of guest molecules such as solubility enhancement and stabilization of labile guests. These properties complemented with the possibility of using different crosslinkers and high polymeric surface, make these sponges highly suitable for a large range of applications. Despite that, in the last 2 decades, cyclodextrin-based nanosponges have been developed for pharmaceutical and biomedical applications, taking advantage of the nontoxicity of cyclodextrins towards humans. This paper provides a critical and timely compilation of the contributions involving cyclodextrins nanosponges for those areas, but also paves the way for other important applications, including water and soil remediation and catalysis.

Cyclodextrin-Based Nanosponges as Perse Antimicrobial Agents Increase the Activity of Natural Antimicrobial Peptide Nisin

At present, antibiotic resistance is considered a real problem. Therefore, for decades scientists have been looking for novel strategies to treat bacterial infections. Nisin Z, an antimicrobial peptide (AMP), can be considered an option, but its usage is mainly limited by the poor stability and short duration of its antimicrobial activity. In this context, cyclodextrin (CD)-based nanosponges (NSs), synthesized using carbonyldiimidazole (CDI) and pyromellitic dianhydride (PMDA), were chosen for nisin Z loading. To determine the minimum inhibitory of nisin Z loaded on CD-NS formulations, agar well diffusion plates were used. Then, the bactericide concentrations of nisin Z loaded on CD-NS formulations were determined against Gram-positive (Staphylococcus aureus) and -negative (Escherichia coli) bacteria, using microdilution brain heart infusion (BHI) and tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). The minimum and bactericide inhibitory values of the nisin complex with NSs were potentially decreased against both bacteria, compared with the nisin-free sample, while the nisin complex with β-CD showed lower antibacterial activity. The antimicrobial effect was also demonstrated by free NSs. Furthermore, the total viable counts (TVCs) antibacterial experiment indicated that the combination of nisin Z in both PMDA and CDI β-CD-based NSs, especially CDI, can provide a better conservative effect on cooked chicken meat. Generally, the present study outcomes suggest that the cross-linked β-CD-based NSs can present their own antimicrobial potency or serve as promising carriers to deliver and enhance the antibacterial action of nisin Z.

The ascension of nanosponges as a drug delivery carrier: preparation, characterization, and applications

Nanosponges are nanosized drug carriers with a three-dimensional structure created by crosslinking polymers. They have the advantage of being able to hold a wide range of drugs of various sizes. Nanosponges come in a variety of shapes and sizes. They are distinguished by the research method used, the type of polymer used, and the type of drug they may contain. Nanosponges are superior to other delivery systems because they can provide a controlled drug release pattern with targeted drug delivery. The period of action, as well as the drug's residence time, may be regulated. Since it is made of biodegradable materials, it has a low toxicity and is safe to use. The efficiency of drug encapsulation is determined by the size of the drug molecule and the amount of void space available. Cancer, enzyme and biocatalyst carrier, oxygen delivery, solubility enhancement, enzyme immobilization, and poison absorbent are some of the applications for nanosponges. The method of preparation, characterization, factors affecting nanosponge development, drug loading and release mechanism, recent developments in this area, and patents filed in the area of nanosponges are all highlighted in this study. Graphical abstract.

Nanocarrier Systems in Taste Masking

Taste is the most crucial organoleptic parameter affecting patient compliance in the case of drugs with poor palatability. Taste masking is a major challenge for the development of orally ingested active pharmaceutical constituents in the pharmaceutical industry. Numerous conventional taste-masking techniques have been extensively studied. In parallel, affecting the drug solubility or release is a major concern of conventional taste-masking techniques. Recently, many nanocarrier systems have been introduced, claiming the advantage of effective taste masking without affecting either the drug solubility or its release. In this review, we will present new techniques for taste masking, including taste-masking techniques utilizing nanocarrier systems such as liposomes, polymeric and solid lipid nanoparticles, polymeric micelles, submicron lipid emulsions, and nanogels. We will chiefly highlight the composition of these systems and their applications in designing oral therapeutic delivery systems successful in masking the taste of bitter molecules.

Nanosponge Approach -A Plethora of Opportunities as a Promising Nanocarrier for Novel Drug Delivery

BACKGROUND

Nanotechnology is the need of the hour! The design of nanotechnologyaided carriers as a tool for the delivery of low solubility molecules offers a potential platform to overcome the issues of current clinical treatment and achieve good targeted release and bioaccessibility.

OBJECTIVE

Nanosponges (NS) encapsulate types of nanocarriers capable of carrying both lipophilic and hydrophilic substances. They are synthesized by mixing a solution of polyester, which is biodegradable, with cross-linkers. These tiny, porous structures are round-shaped, having multiple cavities wherein drugs can be housed to offer programmable release.

METHODS

The detailed literature review and patent search summarize the ongoing research on NS. Substances such as poorly soluble drugs, nutraceuticals, gases, proteins and peptides, volatile oils, genetic material, etc., can be loaded on these novel carriers, which are characterized using various analytical techniques. Target-specific drug delivery and controlled drug release are the advantages offered by NS, along with a myriad of other promising applications.

RESULTS

This review stresses the development of cyclodextrin-based NS, the synthetic methods and characterization of NS, along with factors affecting NS formation, their applications and information on the patented work in this area. NS are solid in character and can be formulated in various dosage forms, such as parenteral, topical, oral or inhalation.

CONCLUSION

Therefore, owing to their promising benefits over other nanocarriers in terms of drug loading, adaptability, sustainability, solubility and tailored release profile, NS is an immediate technological revolution for drug entrapment and as novel drug carriers.The authors expect that these fundamental applications of NS could help the researchers to develop and gain insight about NS in novel drug delivery applications.

Cyclodextrins: Structural, Chemical, and Physical Properties, and Applications

Due to their unique structural, physical and chemical properties, cyclodextrins and their derivatives have been of great interest to scientists and researchers in both academia and industry for over a century. Many of the industrial applications of cyclodextrins have arisen from their ability to encapsulate, either partially or fully, other molecules, especially organic compounds. Cyclodextrins are non-toxic oligopolymers of glucose that help to increase the solubility of organic compounds with poor aqueous solubility, can mask odors from foul-smelling compounds, and have been widely studied in the area of drug delivery. In this review, we explore the structural and chemical properties of cyclodextrins that give rise to this encapsulation (i.e., the formation of inclusion complexes) ability. This review is unique from others written on this subject because it provides powerful insights into factors that affect cyclodextrin encapsulation. It also examines these insights in great detail. Later, we provide an overview of some industrial applications of cyclodextrins, while emphasizing the role of encapsulation in these applications. We strongly believe that cyclodextrins will continue to garner interest from scientists for many years to come, and that novel applications of cyclodextrins have yet to be discovered.

Advances in Controlled-Release Pesticide Formulations with Improved Efficacy and Targetability

Pesticides are commonly used in modern agriculture and are important for global food security. However, postapplication losses due to degradation, photolysis, evaporation, leaching, surface runoff, and other processes may substantially reduce their efficacy. Controlled-release formulations can achieve the permeation-regulated transfer of an active ingredient from a reservoir to a target surface. Thus, they can maintain an active ingredient at a predetermined concentration for a specified period. This can reduce degradation and dissipation and other losses and has the potential to improve efficacy. Recent developments in controlled-release technology have adapted the concepts of intelligence and precision from the pharmaceutical industry. In this review, we present recent advances in the development of controlled-release formulations and discuss details of the preparation methods, material improvements, and application technologies.

Fabrication and Biological Assessment of Antidiabetic α-Mangostin Loaded Nanosponges: In Vitro, In Vivo, and In Silico Studies

Type 2 diabetes mellitus has been a major health issue with increasing morbidity and mortality due to macrovascular and microvascular complications. The urgent need for improved methods to control hyperglycemic complications reiterates the development of innovative preventive and therapeutic treatment strategies. In this perspective, xanthone compounds in the pericarp of the mangosteen fruit, especially α-mangostin (MGN), have been recognized to restore damaged pancreatic β-cells for optimal insulin release. Therefore, taking advantage of the robust use of nanotechnology for targeted drug delivery, we herein report the preparation of MGN loaded nanosponges for anti-diabetic therapeutic applications. The nanosponges were prepared by quasi-emulsion solvent evaporation method. Physico-chemical characterization of formulated nanosponges with satisfactory outcomes was performed with Fourier transform infra-red (FTIR) spectroscopy, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Zeta potential, hydrodynamic diameter, entrapment efficiency, drug release properties, and stability studies at stress conditions were also tested. Molecular docking analysis revealed significant interactions of α-glucosidase and MGN in a protein-ligand complex. The maximum inhibition by nanosponges against α-glucosidase was observed to be 0.9352 ± 0.0856 µM, 3.11-fold higher than acarbose. In vivo studies were conducted on diabetic rats and plasma glucose levels were estimated by HPLC. Collectively, our findings suggest that MGN-loaded nanosponges may be beneficial in the treatment of diabetes since they prolong the antidiabetic response in plasma and improve patient compliance by slowly releasing MGN and requiring less frequent doses, respectively.

Formulation Development, In Vitro and In Vivo Evaluation of Topical Hydrogel Formulation of Econazole Nitrate-Loaded β-Cyclodextrin Nanosponges

Econazole nitrate, an antifungal drug used in the handling of skin ailments, is commercially not efficient as these ailments typically require a more elevated concentration of the drug to offer an effective pharmacological retort. Like so, it is proposed to assess the effectiveness of the topical hydrogel of econazole-loaded nanosponge in the management of skin ailment(s). Econazole nitrate-laden β-cyclodextrin nanosponges were developed by employing the melt method using β-cyclodextrin as the organic polymer and N,N-carbonyldiimidazole as the crosslinker. The critical factors disturbing the quality of the formulation were uniquely identified by the Ishikawa diagram, and they were optimized by the statistical experiment design concept. β-cyclodextrin loaded nanosponges were uniquely designed using the Placket-Burman approach and optimized utilizing the Box-Behnken method. The optimized nanosponges (EN-CDN) were  421.37 ± 6.19 nm in size with an entrapment efficiency of 70.13% ± 5.73%. The topical hydrogel of nanosponges (EN-TG) was prepared using carbopol 934 and pyrrolidone as permeation enhancers. In vitro skin permeation studies affirmed the improved transport crosswise the goatskin for topical hydrogel in comparison to the marketed product. EN-TG was able to control the fungal infection in the selected animal model in comparison to the marketed preparation. Stability studies reported favorably that nanogel remained stable under normal and accelerated settings.

Cyclodextrins in the antiviral therapy

The main antiviral drug-cyclodextrin interactions, changes in physicochemical and physiological properties of the most commonly used virucides are summarized. The potential complexation of antiviral molecules against the SARS-Cov2 also pointed out the lack of detailed information in designing effective and general medicines against viral infections. The principal problem of the current molecules is the 3D structures of the currently active compounds. Improving the solubility or bioavailability of antiviral molecules is possible, however, there is no universal solution, and the complexation experiments dominantly use the already approved cyclodextrin derivatives. This review discusses the basic properties of the different cyclodextrin derivatives, their potential in antiviral formulations, and the prevention and treatment of viral infections. The biologically active new cyclodextrin derivatives are also discussed.

Formulation and in vitro evaluation of topical nanosponge-based gel containing butenafine for the treatment of fungal skin infection

In the current study, four formulae (BNS1-BNS4) of butenafine (BTF) loaded nanosponges (NS) were fabricated by solvent emulsification technology, using different concentration of ethyl cellulose (EC) and polyvinyl alcohol (PVA) as a rate retarding polymer and surfactant, respectively. Prepared NS were characterized for particle size (PS), polydispersity index (PDI), zeta potential (ZP), entrapment efficiency (EE) and drug loading (DL). Nanocarrier BNS3 was optimized based on the particle characterizations and drug encapsulation. It was further evaluated for physicochemical characterizations; FTIR, DSC, XRD and SEM. Selected NS BNS3 composed of BTF (100 mg), EC (200 mg) and 0.3% of PVA showed, PS (543 ± 0.67 nm), PDI (0.330 ± 0.02), ZP (-33.8 ± 0.89 mV), %EE (71.3 ± 0.34%) and %DL (22.8 ± 0.67%), respectively. Fabricated NS also revealed; polymer-drug compatibility, drug-encapsulation, non-crystalline state of the drug in the spherical NS as per the physicochemical evaluations. Optimized NS (BNS3) with equivalent amount of (1%, w/w or w/v) BTF was incorporated into the (1%, w/w or w/v) carbopol gel. BTF loaded NS based gel was then evaluated for viscosity, spreadability, flux, drug diffusion, antifungal, stability and skin irritation studies. BNS3 based topical gels exhibited a flux rate of 0.18 (mg/cm2.h), drug diffusion of 89.90 ± 0.87% in 24 h with Higuchi model following anomalous non-Fickian drug release. The BNS3 based-gel could be effective against pathogenic fungal strains.

Gold nanoparticle-conjugated nanomedicine: design, construction, and structure-efficacy relationship studies

In comparison with conventional therapies, nanomedicine shows prominent clinical performance, with better therapeutic efficacy and less off-target toxicity. As an important component of nanomedicine, gold nanoparticle (GNP)-based nanodrugs have attracted considerable interest because of their excellent performance given by the unique structure. Although no pharmaceutical formulations of GNP-associated nanodrugs have been officially marketed yet, a substantial amount of research on this aspect is being carried out, producing numerous GNP-based drug delivery systems with potential clinical applications. In this review, we present an overview of our progress on GNP-based nanodrugs combined with other achievements in biomedical applications, including drug-conjugated GNPs prepared for disease treatments and specific tumour targeting, structure-efficacy relationship (SER) studies on GNP-conjugated nanodrugs, and therapeutic hybrid nanosystems composed of GNPs. In addition, we also put forward some proposals to guide future work in developing GNP-based nanomedicine. We hope that this review will offer some useful experience for our peers and GNP-based nanodrugs will be utilized in the clinic with further persistent efforts.

Effect of the Cross-Linking Density on the Swelling and Rheological Behavior of Ester-Bridged β-Cyclodextrin Nanosponges

The cross-linking density influences the physicochemical properties of cyclodextrin-based nanosponges (CD-NSs). Although the effect of the cross-linker type and content on the NSs performance has been investigated, a detailed study of the cross-linking density has never been performed. In this contribution, nine ester-bridged NSs based on β-cyclodextrin (β-CD) and different quantities of pyromellitic dianhydride (PMDA), used as a cross-linking agent in stoichiometric proportions of 2, 3, 4, 5, 6, 7, 8, 9, and 10 moles of PMDA for each mole of CD, were synthesized and characterized in terms of swelling and rheological properties. The results, from the swelling experiments, exploiting Flory-Rehner theory, and rheology, strongly showed a cross-linker content-dependent behavior. The study of cross-linking density allowed to shed light on the efficiency of the synthesis reaction methods. Overall, our study demonstrates that by varying the amount of cross-linking agent, the cross-linked structure of the NSs matrix can be controlled effectively. As PMDA βCD-NSs have emerged over the years as a highly versatile class of materials with potential applications in various fields, this study represents the first step towards a full understanding of the correlation between their structure and properties, which is a key requirement to effectively tune their synthesis reaction in view of any specific future application or industrial scale-up.

Gut Microbiota Combined With Metabolomics Reveals the Repeated Dose Oral Toxicity of β-Cyclodextrin in Mice

Βeta-cyclodextrin (β-CD) with a hydrophobic cavity enables the formation of inclusion complexes with organic molecules. The formation of host–guest complexes makes the application of β-CD popular in many fields, but their interaction with organisms is poorly understood. In the present study, the effect of β-CD on gut microbiota (16S rRNA gene sequencing), serum metabolites (gas chromatography–mass spectrometry platform), and their correlation (Pearson correlation analysis) was investigated after 14 days repeated oral exposure in mice. β-CD did not significantly affect the α-diversity indexes, including Richness, Chao1, Shannon and Simpson indexes, but disturbed the structure of the gut bacteria according to the result of principal component analysis (PCA). After taxonomic assignment, 1 in 27 phyla, 2 in 48 classes, 3 in 107 orders, 6 in 192 families, and 8 in 332 genera were significantly different between control and β-CD treated groups. The serum metabolites were significantly changed after β-CD treatment according to the result of unsupervized PCA and supervised partial least squares-discriminant analysis (PLS-DA). A total of 112 differential metabolites (89 downregulated and 23 upregulated) were identified based on the VIP >1 from orthogonal PLS-DA and p <0.05 from Student’s t-test. The metabolic pathways, including ABC transporters, pyrimidine metabolism, purine metabolism, glucagon signaling pathway, insulin signaling pathway, and glycolysis/gluconeogenesis, were enriched by KEGG pathway analysis. Our study provides a general observation of gut microbiota, serum metabolites and their correlation after exposure to β-CD in mice, which will be helpful for future research and application of β-CD.

Oral Nano Drug Delivery Systems for the Treatment of Type 2 Diabetes Mellitus: An Available Administration Strategy for Antidiabetic Phytocompounds

In view of the worldwide serious health threat of type 2 diabetes mellitus (T2DM), natural sources of chemotherapies have been corroborated as the promising alternatives, with the excellent antidiabetic activities, bio-safety, and more cost-effective properties. However, their clinical application is somewhat limited, because of the poor solubility, instability in the gastrointestinal tract (GIT), low bioavailability, and so on. Nowadays, to develop nanoscaled systems has become a prominent strategy to improve the drug delivery of phytochemicals. In this review, we primarily summarized the intervention mechanisms of phytocompounds against T2DM and presented the recent advances in various nanosystems of antidiabetic phytocompounds. Selected nanosystems were grouped depending on their classification and structures, including polymeric NPs, lipid-based nanosystems, vesicular systems, inorganic nanocarriers, and so on. Based on this review, the state-of-the-art nanosystems for phytocompounds in T2DM treatment have been presented, suggesting the preponderance and potential of nanotechnologies.

The use of plant extracts and their phytochemicals for control of toxigenic fungi and mycotoxins

Mycotoxins present a great concern to food safety and security due to their adverse health and socio-economic impacts. The necessity to formulate novel strategies that can mitigate the economic and health effects associated with mycotoxin contamination of food and feed commodities without any impact on public health, quality and nutritional value of food and feed, economy and trade industry become imperative. Various strategies have been adopted to mitigate mycotoxin contamination but often fall short of the required efficacy. One of the promising approaches is the use of bioactive plant components/metabolites synergistically with mycotoxin-absorbing components in order to limit exposure to these toxins and associated negative health effects. In particular, is the fabrication of β-cyclodextrin-based nanosponges encapsulated with bioactive compounds of plant origin to inhibit toxigenic fungi and decontaminate mycotoxins in food and feed without leaving any health and environmental hazard to the consumers. The present paper reviews the use of botanicals extracts and their phytochemicals coupled with β-cyclodextrin-based nanosponge technology to inhibit toxigenic fungal invasion and detoxify mycotoxins.

Comprehensive Review on Current Interventions, Diagnostics, and Nanotechnology Perspectives against SARS-CoV-2

The coronavirus disease 2019 (COVID-19) has dramatically challenged the healthcare system of almost all countries. The authorities are struggling to minimize the mortality along with ameliorating the economic downturn. Unfortunately, until now, there has been no promising medicine or vaccine available. Herein, we deliver perspectives of nanotechnology for increasing the specificity and sensitivity of current interventional platforms toward the urgent need of quickly deployable solutions. This review summarizes the recent involvement of nanotechnology from the development of a biosensor to fabrication of a multifunctional nanohybrid system for respiratory and deadly viruses, along with the recent interventions and current understanding about severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Design and formulation of polymeric nanosponge tablets with enhanced solubility for combination therapy

Three drugs namely caffeine, paracetamol, and aceclofenac are commonly used for treating various acute and chronic pain related ailments. These 3 drugs have varied solubility profiles, and formulating them into a single tablet did not have the desired dissolution profile for drug absorption. The objective of the present research was to tailor the drug release profile by altering drug solubility. This was achieved by loading the drug into nanosponges. Here, three-dimensional colloidal nanosponges were prepared using β-cyclodextrin with dimethyl carbonate as a cross-linker using the hot-melt compression method. The prepared nanosponges were characterized by FTIR, ¹H NMR spectroscopy, DSC, XRPD studies and SEM. The FTIR and DSC results obtained indicated polymer-drug compatibility. The ¹H NMR spectroscopy results obtained indicated the drug entrapment within nanosponges with the formation of the inclusion complex. XRPD studies showed that the loaded drug had changed crystalline properties altering drug solubility. SEM photographs revealed the porous and spongy texture on the surface of the nanosponge. Box–Behnken experimental design was adopted for the optimization of nanosponge synthesis. Among the synthesized nanosponges containing paracetamol, aceclofenac and caffeine, batch F3–P31, F3–A31 and F3–C31 were considered optimized. Their particle size was 185, 181 and 199 nm with an entrapment efficiency of 81.53, 84.96, and 89.28% respectively. These optimized nanosponges were directly compressed into tablets and were studied for both pre and post-compression properties including in vitro drug release. The prepared tablet showed desired drug dissolution properties compared to the pure drug. The above outcomes indicated the applicability of nanosponges in modulating the drug release with varied solubility for combination therapy.

Polymeric nanosponges as potential carriers for successful combination therapy of poorly soluble drugs (paracetamol, aceclofenac, caffeine).

History of Cyclodextrin Nanosponges

Nowadays, research in the field of nanotechnology and nanomedicine has become increasingly predominant, focusing on the manipulation and development of materials on a nanometer scale. Polysaccharides have often been used as they are safe, non-toxic, hydrophilic, biodegradable and are low cost. Among them, starch derivatives and, in particular, cyclodextrin-based nanosponges (CD NSs) have recently emerged due to the outstanding properties attributable to their peculiar structure. In fact, alongside the common polysaccharide features, such as the presence of tunable functional groups and their ability to interact with biological tissues, thus giving rise to bioadhesion, which is particularly useful in drug delivery, what makes CD NSs unique is their three-dimensional network made up of crosslinked cyclodextrin units. The name “nanosponge” appeared for the first time in the 1990s due to their nanoporous, sponge-like structure and responded to the need to overcome the limitations of native cyclodextrins (CDs), particularly their water solubility and inability to encapsulate charged and large molecules efficiently. Since CD NSs were introduced, efforts have been made over the years to understand their mechanism of action and their capability to host molecules with low or high molecular weight, charged, hydrophobic or hydrophilic by changing the type of cyclodextrin, crosslinker and degree of crosslinking used. They enabled great advances to be made in various fields such as agroscience, pharmaceutical, biomedical and biotechnological sectors, and NS research is far from reaching its conclusion. This review gives an overview of CD NS research, focusing on the origin and key points of the historical development in the last 50 years, progressing from relatively simple crosslinked networks in the 1960s to today’s multifunctional polymers. The approach adopted in writing the present study consisted in exploring the historical evolution of NSs in order to understand their role today, and imagine their future.

Water Dynamics at the Solid-Liquid Interface to Unveil the Textural Features of Synthetic Nanosponges

A fast-field-cycling NMR investigation was carried out on a set of polyurethane cyclodextrin nanosponges, in order to gain information on their textural properties, which have been proven to be quite difficult to assess by means of ordinary porosimetric techniques. Experiments were performed on both dry and wet samples, in order to evaluate the behavior of the “nonexchangeable” C-bound ¹H nuclei, as well as the one of the mobile protons belonging to the skeletal hydroxyl groups and the water molecules. The results acquired for the wet samples accounted for the molecular mobility of water molecules within the channels of the nanosponge network, leading back to the possible pore size distribution. Owing to the intrinsic difficulties involved in a quantitative assessment of the textural properties, in the present study we alternatively propose an extension to nanosponges of the concept of “connectivity”, which has been already employed to discuss the properties of soils.