A vision for cyclodextrin nanoparticles in drug delivery systems and pharmaceutical applications

Controlled release characteristics of alkyl gallates and gallic acid from β-cyclodextrin inclusion complexes of alkyl gallates

The freeze-drying approach was used to create inclusion complexes utilizing alkyl gallates and β-cyclodextrin, namely dodecyl gallate, octyl gallate, butyl gallate, and ethyl gallate, which are exemplary examples of phenolic esters. The everted-rat-gut-sac model demonstrated that the inclusion complexes released alkyl gallates, which were subsequently hydrolyzed to generate free gallic acid, as evidenced by HPLC-UV analysis. Both gallic acid and short-chain alkyl gallates were capable of permeating the small intestinal membrane. The transport rate of gallic acid (or alkyl gallates) exhibited an initial rise followed by a drop when the carbon-chain lengths varied. The inclusion complex groups exhibited a superior sustained-release effect compared to the comparable alkyl gallates groups, thus possibly leading to higher bioavailability and stronger bioactivity. Moreover, altering the length of the carbon chain will allow for the effortless achievement of regulated release of phenolic compounds and short-chain phenolic esters from such β-cyclodextrin inclusion complexes.

A Comprehensive Review of Nanoparticles: From Classification to Application and Toxicity

Nanoparticles are structures that possess unique properties with high surface area-to-volume ratio. Their small size, up to 100 nm, and potential for surface modifications have enabled their use in a wide range of applications. Various factors influence the properties and applications of NPs, including the synthesis method and physical attributes such as size and shape. Additionally, the materials used in the synthesis of NPs are primary determinants of their application. Based on the chosen material, NPs are generally classified into three categories: organic, inorganic, and carbon-based. These categories include a variety of materials, such as proteins, polymers, metal ions, lipids and derivatives, magnetic minerals, and so on. Each material possesses unique attributes that influence the activity and application of the NPs. Consequently, certain NPs are typically used in particular areas because they possess higher efficiency along with tenable toxicity. Therefore, the classification and the base material in the NP synthesis hold significant importance in both NP research and application. In this paper, we discuss these classifications, exemplify most of the major materials, and categorize them according to their preferred area of application. This review provides an overall review of the materials, including their application, and toxicity.

β-cyclodextrin inclusion complexes with short-chain phenolipids: An effective formulation for the dual sustained-release of phenolic compounds

The β-cyclodextrin and short-chain alkyl gallates (A-GAs), which are representative of phenolipids, such as butyl, propyl, ethyl, and methyl gallates, were chosen to form inclusion complexes by the use of the freeze-drying process. In the everted rat gut sac model, HPLC-UV analysis demonstrated that the released A-GAs from inclusion complexes were degraded to yield free gallic acid (GA) (sustained-release function 1). The small intestine membrane may be crossed by both the GA and the A-GAs. A-GAs may also undergo hydrolysis to provide GA (sustained-release function 2) following transmembrane transfer. Clearly, a helpful technique for the dual sustained-release of phenolic compounds is to produce β-cyclodextrin inclusion complexes with short-chain phenolipids. This will increase the bioactivities of phenolic compounds and prolong their in vivo residence length. Moreover, changing the carbon-chain length of these β-cyclodextrin inclusion complexes would readily modify the dual sustained-release behavior of the phenolic compounds. Thus, our work effectively established a theoretical foundation for the use of β-cyclodextrin inclusion complexes containing short-chain phenolipids as new source of functional food components to provide the body with phenolic compounds more efficiently.

β-Cyclodextrin functionalized agarose-based hydrogels for multiple controlled drug delivery of ibuprofen

Agarose hydrogels are three-dimensional hydrophilic polymeric frameworks characterised by high water content, viscoelastic properties, and excellent ability as cell and drug delivery systems. However, their hydrophilicity as gel systems makes loading of hydrophobic drugs difficult and often ineffective. The incorporation of amphiphilic molecules (e.g. cyclodextrins) into hydrogels as hosts able to form inclusion complexes with hydrophobic drugs could be a possible solution. However, if not properly confined, the host compounds can get out of the network resulting in uncontrolled release. Therefore, in this work, β-cyclodextrins-based host-guest supramolecular hydrogel systems were synthesised, with β-cyclodextrins (β-CD) covalently bound to the polymeric network, preventing leakage of the host molecules. Hydrogels were prepared at two different β-CD-functionalized polyvinyl alcohol (PVA)/agarose ratios, and characterised chemically and physically. Then ibuprofen, a drug often used as a gold standard in studies involving β-CD both in its hydrophilic and hydrophobic forms, was selected to investigate the release behavior of the synthesised hydrogels and the influence of β-CD on the release. The presence of β-CD linked to the polymeric 3D network ensured a higher and prolonged release profile for the hydrophobic drug and also seemed to have some influence on the hydrophilic one.

Unraveling the Interaction of Diflunisal with Cyclodextrin and Lysozyme by Fluorescence Spectroscopy

Understanding the interaction between the drug:carrier complex and protein is essential for the development of a new drug-delivery system. However, the majority of reports are based on an understanding of interactions between the drug and protein. Here, we present our findings on the interaction of the anti-inflammatory drug diflunisal with the drug carrier cyclodextrin (CD) and the protein lysozyme, utilizing steady-state and time-resolved fluorescence spectroscopy. Our findings reveal a different pattern of molecular interaction between the inclusion complex of β-CD (β-CD) or hydroxypropyl-β-CD (HP-β-CD) (as the host) and diflunisal (as the guest) in the presence of protein lysozyme. The quantum yield for the 1:2 guest:host complex is twice that of the 1:1 guest:host complex, indicating a more stable hydrophobic microenvironment created in the 1:2 complex. Consequently, the nonradiative decay pathway is significantly reduced. The interaction is characterized by ultrafast solvation dynamics and time-resolved fluorescence resonance energy transfer. The solvation dynamics of the lysozyme becomes 10% faster under the condition of binding with the drug, indicating a negligible change in the polar environment after binding. In addition, the fluorescence lifetime of diflunisal (acceptor) is increased by 50% in the presence of the lysozyme (donor), which indicates that the drug molecule is bound to the binding pocket on the surface of the protein, and the average distance between active tryptophan in the hydrophobic region and diflunisal is calculated to be approximately 50 Å. Excitation and emission matrix spectroscopy reveals that the tryptophan emission increases 3-5 times in the presence of both diflunisal and CD. This indicates that the tryptophan of lysozyme may be present in a more hydrophobic environment in the presence of both diflunisal and CD. Our observations on the interaction of diflunisal with β-CD and lysozyme are well supported by molecular dynamics simulation. Results from this study may have an impact on the development of a better drug-delivery system in the future. It also reveals a fundamental molecular mechanism of interaction of the drug-carrier complex with the protein.

Supramolecular nanomedicines based on host-guest interactions of cyclodextrins

In the biomedical and pharmaceutical fields, cyclodextrin (CD) is undoubtedly one of the most frequently used macrocyclic compounds as the host molecule because it has good biocompatibility and can increase the solubility, bioavailability, and stability of hydrophobic drug guests. In this review, we generalized the unique properties of CDs, CD-related supramolecular nanocarriers, supramolecular controlled release systems, and targeting systems based on CDs, and introduced the paradigms of these nanomedicines. In addition, we also discussed the prospects and challenges of CD-based supramolecular nanomedicines to facilitate the development and clinical translation of these nanomedicines.

Preparation and Characterization of a Nano-Inclusion Complex of Quercetin with β-Cyclodextrin and Its Potential Activity on Cancer Cells

Quercetin (QRC), a flavonoid found in foods and plants such as red wine, onions, green tea, apples, and berries, possesses remarkable anti-inflammatory and antioxidant properties. These properties make it effective in combating cancer cells, reducing inflammation, protecting against heart disease, and regulating blood sugar levels. To enhance the potential of inclusion complexes (ICs) containing β-cyclodextrin (β-CD) in cancer therapy, they were transformed into nano-inclusion complexes (NICs). In this research, NICs were synthesized using ethanol as a reducing agent in the nanoprecipitation process. By employing FT-IR analysis, it was observed that hydrogen bonds were formed between QRC and β-CD. Moreover, the IC molecules formed NICs through the aggregation facilitated by intermolecular hydrogen bonds. Proton NMR results further confirmed the occurrence of proton shielding and deshielding subsequent to the formation of NICs. The introduction of β-CDs led to the development of a distinctive feather-like structure within the NICs. The particle sizes were consistently measured around 200 nm, and both SAED and XRD patterns indicated the absence of crystalline NICs, providing supporting evidence. Through cytotoxicity and fluorescence-assisted cell-sorting analysis, the synthesized NICs showed no significant damage in the cell line of MCF-7. In comparison to QRC alone, the presence of high concentrations of NICs exhibited a lesser degree of toxicity in normal human lung fibroblast MRC-5 cells. Moreover, the individual and combined administration of both low and high concentrations of NICs effectively suppressed the growth of cancer cells (MDA-MB-231). The solubility improvement resulting from the formation of QRC-NICs with β-CD enhanced the percentage of cell survival for MCF-7 cell types.

Enhancement of the oral bioavailability of isopropoxy benzene guanidine though complexation with hydroxypropyl-β-cyclodextrin

Isopropoxy benzene guanidine (IBG) is a novel substituted benzene guanidine analogue with antibacterial activity against multidrug-resistant bacteria. However, the bioavailability of IBG is not optimal due to its finite aqueous solubility, thus hampering its potential therapeutic exploitation. In this study, we prepared IBG/hydroxypropyl-β-CD (IBG/HP-β-CD) complex, and characterized it by differential scanning calorimetry, Fourier transform infrared spectroscopy, powder X-ray diffraction, and scanning electron microscopy. Physicochemical characterization indicated that the crystal morphology of IBG transformed into an amorphous state, thus forming IBG/HP-β-CD inclusion complexes. Complexation with HP-β-CD significantly improve the aqueous solubility, pharmaceutical properties, absorption, and bioavailability of IBG.

A Review of Multifunction Smart Nanoparticle based Drug Delivery Systems

Cancer nano-therapeutics are rapidly evolving and are often used to overcome a number of concerns with traditional drug delivery methods, including non-specific drug targeting and distribution, low oral bioavailability, and poor hydrophilicity. Modern nano-based targeting techniques have been developed as a result of advances in nano vehicle engineering and materials science, which may bring people with cancer a new hope. Clinical trials have been authorized for a number of medicinal nanocarriers. Nanocarriers with the best feasible size and surface attributes have been developed to optimize biodistribution and increase blood circulation duration. Nanotherapeutics can carry preloaded active medicine towards cancerous cells by preferentially leveraging the specific physiopathology of malignancies. In contrast to passive targeting, active targeting strategies involving antigens or ligands, developed against specific tumor sites, boost the selectivity of these curative nanovehicles. Another barrier that nanoparticles may resolve or lessen is drug resistance. Multifunctional and complex nanoparticles are currently being explored and are predicted to usher in a new era of nanoparticles that will allow for more individualized and customized cancer therapy. The potential prospects and opportunities of stimuli-triggered nanosystems in therapeutic trials are also explored in this review.

Cyclodextrin nanoparticles for diagnosis and potential cancer therapy: A systematic review

Cancer is still one of the world’s deadliest health concerns. As per latest statistics, lung, breast, liver, prostate, and cervical cancers are reported topmost worldwide. Although chemotherapy is most widely used methodology to treat cancer, poor pharmacokinetic parameters of anticancer drugs render them less effective. Novel nano-drug delivery systems have the caliber to improve the solubility and biocompatibility of various such chemical compounds. In this regard, cyclodextrins (CD), a group of natural nano-oligosaccharide possessing unique physicochemical characteristics has been highly exploited for drug delivery and other pharmaceutical purposes. Their cup-like structure and amphiphilic nature allows better accumulation of drugs, improved solubility, and stability, whereas CDs supramolecular chemical compatibility renders it to be highly receptive to various kinds of functionalization. Therefore combining physical, chemical, and bio-engineering approaches at nanoscale to specifically target the tumor cells can help in maximizing the tumor damage without harming non-malignant cells. Numerous combinations of CD nanocomposites were developed over the years, which employed photodynamic, photothermal therapy, chemotherapy, and hyperthermia methods, particularly targeting cancer cells. In this review, we discuss the vivid roles of cyclodextrin nanocomposites developed for the treatment and theranostics of most important cancers to highlight its clinical significance and potential as a medical tool.

Cyclodextrin metal-organic frameworks and derivatives: recent developments and applications

While there is a tremendous amount of scientific research on metal organic frameworks (MOFs) for gas storage/separation, catalysis and energy storage, the development and application of biocompatible MOFs still poses major challenges. In general, they can be synthesised from various biocompatible linkers and metal ions but particularly cyclodextrins (CDs) as cyclic oligosaccharides are an astute choice for the former. Although the field of CD-MOF materials is still in the early stages and their design and fabrication comes with many hurdles, the benefits coming from CDs built in a porous framework are exciting. Versatile host-guest complexation abilities, high encapsulation capacity and hydrophilicity are among the valuable properties inherent to CDs and offer extended and novel applications to MOFs. In this review, we provide an overview of the state-of-the-art synthesis, design, properties and applications of these materials. Initially, a rationale for the preparation of CD-based MOFs is provided, based on the chemical and structural properties of CDs and including their advantages and disadvantages. Further on, the review exhaustively surveys CD-MOF based materials by categorising them into three sub-classes, namely (i) CD-MOFs, (ii) CD-MOF hybrids, obtained via combination with external materials, and (iii) CD-MOF-derived materials prepared under pyrolytic conditions. Subsequently, CD-based MOFs in practical applications, such as drug delivery and cancer therapy, sensors, gas storage, (enantiomer) separations, electrical devices, food industry, and agriculture, are discussed. We conclude by summarizing the state of the art in the field and highlighting some promising future developments of CD-MOFs.

Topological defects in polycrystalline hexosomes from β-cyclodextrin fatty esters

Colloidal nanoparticles were prepared by aqueous self-assembly of amphiphilic β-cyclodextrins (βCDs) acylated on their secondary face with C₁₄ chains to a total degree of substitution of 7.0, via a thermolysin-catalyzed transesterification process. The small-angle X-ray scattering pattern of the nanoparticles was consistent with a reverse hexagonal organization. Cryo-transmission electron microscopy images revealed particles with spectacular tortuous shapes and consisting of misoriented domains with a regular columnar hexagonal structure, separated by sharp interfaces. Edge dislocations as well as a variety of stepped tilt grain boundaries (GBs) composed of symmetrical and asymmetrical sections, together with one twist GB, were identified from axial views of the columnar organization. The tilt GB structure was analyzed using the concepts of coincidence site lattice and structural units developed to describe the atomic structure of interfaces in various types of polycrystals. The tilt GBs were described using sequences of βCD-C₁₄ columns that differed by the number of neighboring columns (5, 6 or 7) and exhibiting distinctive contrasts. To our knowledge, this is the first time that these types of topological defects are described at the nanometric scale by direct observation of colloidal polycrystalline hexosomes of self-organized amphiphiles.

Partial inclusion complex assisted crosslinked β-cyclodextrin nanoparticles for improving therapeutic potential of docetaxel against breast cancer

The present investigation demonstrates the development of crosslinked β-cyclodextrin nanoparticles (β-CD NPs) for enhancing the therapeutic efficacy of docetaxel (DTX) against breast cancer. Initially, a partial inclusion complex between β-CD and polypropylene glycol (PPG) was formed to induce self-assembly. This was followed by crosslinking of β-CDs using epichlorohydrin (EPI) and removal (by solubilization) of PPG to yield uniform β-CD NPs. The formed particles were used for loading DTX to form DTX β-CD NPs. The resultant DTX β-CD NPs exhibited particle size of 223.36 ± 17.73 nm with polydispersity index (PDI) of 0.13 ± 0.09 and showed entrapment efficiency of 54.53 ± 2%. Increased cell uptake (~5-fold), cytotoxicity (~3.3-fold), and apoptosis were observed in MDA-MB-231 cells when treated with DTX β-CD NPs in comparison to free DTX. Moreover, pharmacokinetic evaluation of DTX β-CD NPs revealed ~2 and ~5-fold increase in AUC0-∞ and mean residence time (MRT) of DTX when compared to Docepar®. Further, the anti-tumor activity using DMBA-induced cancer model showed that DTX β-CD NPs were capable of reducing the tumor volume to ~40%, whereas Docepar® was able to reduce tumor volume till ~80%. Finally, the toxicity evaluation of DTX β-CD NPs revealed no short-term nephrotoxicity and was confirmed by estimating the levels of biomarkers and histopathology of the organs. Thus, the proposed formulation strategy can yield uniformly formed β-CD NPs which can be effectively utilized for improving the therapeutic efficacy of DTX.

Nanoparticle Systems for Cancer Phototherapy: An Overview

Photodynamic therapy (PDT) and photothermal therapy (PTT) are photo-mediated treatments with different mechanisms of action that can be addressed for cancer treatment. Both phototherapies are highly successful and barely or non-invasive types of treatment that have gained attention in the past few years. The death of cancer cells because of the application of these therapies is caused by the formation of reactive oxygen species, that leads to oxidative stress for the case of photodynamic therapy and the generation of heat for the case of photothermal therapies. The advancement of nanotechnology allowed significant benefit to these therapies using nanoparticles, allowing both tuning of the process and an increase of effectiveness. The encapsulation of drugs, development of the most different organic and inorganic nanoparticles as well as the possibility of surfaces' functionalization are some strategies used to combine phototherapy and nanotechnology, with the aim of an effective treatment with minimal side effects. This article presents an overview on the use of nanostructures in association with phototherapy, in the view of cancer treatment.

A New Approach for β-Cyclodextrin Conjugated Drug Delivery System in Cancer Therapy

Natural cyclodextrins (CDs) are macrocyclic starch molecules discovered a decade ago, in which α-, β-, and γ-CD were commonly used. They originally acted as pharmaceutical excipients to enhance the aqueous solubility and alter the physicochemical properties of drugs that fall under class II and IV categories according to the Biopharmaceutics Classification System (BPS). The industrial significance of CDs became apparent during the 1970s as scientists started to discover more of CD's potential in chemical modifications and the formation of inclusion complexes. CDs can help in masking and prolonging the half-life of drugs used in cancer. Multiple optimization techniques were discovered to prepare the derivatives of CDs and increase their complexation and drug delivery efficiency. In recent years, due to the advancement of nanotechnology in pharmaceutical sectors, there has been growing interest in CDs. This review mainly focuses on the formulation of cyclodextrin conjugated nanocarriers using graphenes, carbon nanotubes, nanosponges, hydrogels, dendrimers, and polymers to achieve drug-release characteristics specific to cells. These approaches benefit the discovery of novel anti-cancer treatments, solubilization of new drug compounds, and cell specific drug delivery properties. Due to these unique properties of CDs, they are essential in achieving and enhancing tumor-specific cancer treatment.

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.

Antimicrobial Activity of Curcumin in Nanoformulations: A Comprehensive Review

Curcumin (CUR) is a natural substance extracted from turmeric that has antimicrobial properties. Due to its ability to absorb light in the blue spectrum, CUR is also used as a photosensitizer (PS) in antimicrobial Photodynamic Therapy (aPDT). However, CUR is hydrophobic, unstable in solutions, and has low bioavailability, which hinders its clinical use. To circumvent these drawbacks, drug delivery systems (DDSs) have been used. In this review, we summarize the DDSs used to carry CUR and their antimicrobial effect against viruses, bacteria, and fungi, including drug-resistant strains and emergent pathogens such as SARS-CoV-2. The reviewed DDSs include colloidal (micelles, liposomes, nanoemulsions, cyclodextrins, chitosan, and other polymeric nanoparticles), metallic, and mesoporous particles, as well as graphene, quantum dots, and hybrid nanosystems such as films and hydrogels. Free (non-encapsulated) CUR and CUR loaded in DDSs have a broad-spectrum antimicrobial action when used alone or as a PS in aPDT. They also show low cytotoxicity, in vivo biocompatibility, and improved wound healing. Although there are several in vitro and some in vivo investigations describing the nanotechnological aspects and the potential antimicrobial application of CUR-loaded DDSs, clinical trials are not reported and further studies should translate this evidence to the clinical scenarios of infections.

Nanoparticle encapsulation of non-genotoxic p53 activator Inauhzin-C for improved therapeutic efficacy

The tumor suppressor protein p53 remains in a wild type but inactive form in ~50% of all human cancers. Thus, activating it becomes an attractive approach for targeted cancer therapies. In this regard, our lab has previously discovered a small molecule, Inauhzin (INZ), as a potent p53 activator with no genotoxicity. Method: To improve its efficacy and bioavailability, here we employed nanoparticle encapsulation, making INZ-C, an analog of INZ, to nanoparticle-encapsulated INZ-C (n-INZ-C). Results: This approach significantly improved p53 activation and inhibition of lung and colorectal cancer cell growth by n-INZ-C in vitro and in vivo while it displayed a minimal effect on normal human Wi38 and mouse MEF cells. The improved activity was further corroborated with the enhanced cellular uptake observed in cancer cells and minimal cellular uptake observed in normal cells. In vivo pharmacokinetic evaluation of these nanoparticles showed that the nanoparticle encapsulation prolongates the half-life of INZ-C from 2.5 h to 5 h in mice. Conclusions: These results demonstrate that we have established a nanoparticle system that could enhance the bioavailability and efficacy of INZ-C as a potential anti-cancer therapeutic.

Drug-Encapsulated Cyclodextrin Nanosponges

To date, a number of nanocarriers, either inorganic or organic, have been developed to improve the delivery and therapeutic efficacy of various drugs. Drug delivery systems have attempted to overcome the undesirable pharmacokinetic problems encountered. Among the various nanomaterials that have been designed as potential nanocarriers, cyclodextrin-based polymers are of particular interest in this review.Cyclodextrins (CD) are a class of cyclic glucopyranose oligomers, obtained from starch by enzymatic action, with a characteristic toroidal shape that forms a truncated cone-shaped lipophilic cavity. The main common native cyclodextrins are named α, β, and γ which comprise six, seven, and eight glucopyranose units, respectively. Cyclodextrins have the capability to include compounds whose size and polarity are compatible with those of their cavity.Cyclodextrin-based cross-linked polymers, often referred to as "cyclodextrin nanosponges" (CDNSs), attract great attention from researchers for solving major bioavailability problems such as inadequate solubility, poor dissolution rate, and limited stability of some agents, as well as increasing their effectiveness and decreasing unwanted side effects.Registered patents about this novel system in various fields, different pharmaceutical applications, and classes of drugs encapsulated by CDNSs are detailed. The features outlined make CDNSs a promising platform for the development of innovative and advanced delivery systems.

Inclusion Complexes of Non-Steroidal Anti-Inflammatory Drugs with Cyclodextrins: A Systematic Review

Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the most widely used classes of medicines in the treatment of inflammation, fever, and pain. However, evidence has demonstrated that these drugs can induce significant toxicity. In the search for innovative strategies to overcome NSAID-related problems, the incorporation of drugs into cyclodextrins (CDs) has demonstrated promising results. This study aims to review the impact of cyclodextrin incorporation on the biopharmaceutical and pharmacological properties of non-steroidal anti-inflammatory drugs. A systematic search for papers published between 2010 and 2020 was carried out using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol and the following search terms: “Complexation”; AND “Cyclodextrin”; AND “non-steroidal anti-inflammatory drug”. A total of 24 different NSAIDs, 12 types of CDs, and 60 distinct inclusion complexes were identified, with meloxicam and β-CD appearing in most studies. The results of the present review suggest that CDs are drug delivery systems capable of improving the pharmacological and biopharmaceutical properties of non-steroidal anti-inflammatory drugs.

Monoclonal Antibodies Carried in Drug Delivery Nanosystems as a Strategy for Cancer Treatment

Monoclonal antibodies carried in nanosystems have been extensively studied and reported as a promising tool for the treatment of various types of cancers. Monoclonal antibodies have great advantages for the treatment of cancer because their protein structure can bind to the target tissue; however, it has some challenges such as denaturation following heat exposure and extreme values of pH, temperature and solvents, the ability to undergo hydrolysis, oxidation and deamination and the formation of non-native aggregates, which compromise drug stability to a large extent. In addition to these characteristics, they suffer rapid elimination when in the blood, which results in a short half-life and the production of neutralizing antibodies, rendering the doses ineffective. These challenges are overcome with encapsulation in nanosystems (liposomes, polymer nanoparticles, cyclodextrins, solid lipid nanoparticles, nanostructured lipid carriers, dendrimers and micelles) due to the characteristics of improving solubility, permeability, and selectivity only with tumor tissue; with that, there is a decrease in side effects beyond controlled release, which is critical to improving the therapeutic efficacy of cancer treatment. The article was divided into different types of nanosystems, with a description of their definitions and applications in various types of cancers. Therefore, this review summarizes the use of monoclonal antibodies encapsulated in nanosystems and the description of clinical studies with biosimilars. Biosimilars are defined as products that are similar to monoclonal antibodies which are produced when the patent for the monoclonal antibodies expires.

Main Applications of Cyclodextrins in the Food Industry as the Compounds of Choice to Form Host-Guest Complexes

Cyclodextrins (CDs) are cyclic oligomers broadly used in food manufacturing as food additives for different purposes, e.g., to improve sensorial qualities, shelf life, and sequestration of components. In this review, the latest advancements of their applications along with the characteristics of the uses of the different CDs (α, β, γ and their derivatives) were reviewed. Their beneficial effects can be achieved by mixing small amounts of CDs with the target material to be stabilized. Essentially, they have the capacity to form stable inclusion complexes with sensitive lipophilic nutrients and constituents of flavor and taste. Their toxicity has been also studied, showing that CDs are innocuous in oral administration. A review of the current legislation was also carried out, showing a general trend towards a wider acceptance of CDs as food additives. Suitable and cost-effective procedures for the manufacture of CDs have progressed, and nowadays it is possible to obtain realistic prices and used them in foods. Therefore, CDs have a promising future due to consumer demand for healthy and functional products.

Advances in applied supramolecular technologies

Supramolecular chemistry has successfully built a foundation of fundamental understanding. However, with this now achieved, we show how this area of chemistry is moving out of the laboratory towards successful commercialisation.

The advantages of nanomedicine in the treatment of visceral leishmaniasis: between sound arguments and wishful thinking

Introduction: Although life-threatening if left untreated, visceral leishmaniasis (VL) is still a neglected endemic disease in 98 countries worldwide. The number of drugs available is low and few are in clinical trials. In the last decades, efforts have been made on the development of nanocarriers as drug delivery systems to treat VL. Given the preferential intracellular location of the parasite in the liver and spleen macrophages, the rationale is sturdy. In a clinical setting, liposomal amphotericin B displays astonishing cure rates.Areas covered: A literature search was performed through PubMed and Google Scholar. We critically reviewed the main literature highlighting the success of nanomedicine in VL. We also reviewed the hurdles and yet unfulfilled promises rising awareness of potential drawbacks of nanomedicine in VL.Expert opinion: VL is a disease where nanomedicines successes shine through. However, there are a lot of obstacles on the road to developing more efficient strategies such as targeting functionalization, oral formulations, or combined therapies. And those strategies raise many questions.

Biomedical application of chondroitin sulfate with nanoparticles in drug delivery systems: systematic review

Chondroitin sulphate captured an increasing amount of attention in the field of drug delivery systems. Nanoparticles and chondroitin sulphate were combined in different ways to form effective target nanocarriers. The study aimed to evaluate the biomedical application of chondroitin sulphate with nanoparticles in drug delivery systems. We searched PubMed, Google Scholar, and MEDLINE for studies that included data for the application of chondroitin sulphate and nanoparticles in targeting drug delivery published in English up to 25 February 2020. OHAT (Office of Health Assessment and Translation) Risk-of-Bias Tool was used to assessing the quality and risk of bias of each study. We performed a qualitative synthesis of findings from included studies. The toxicity of developed drugs has been evaluated using cell viability percentage and 50% inhibitory concentration of drugs. Twenty original articles reported the application of chondroitin sulphate on drug delivery systems were selected. Drug loading and encapsulation efficiency were from 2% to 16.1% and from 39.50% to 93.97%, respectively. The drug release was fast at start time and followed by a slow and sustain released stage. The risk of bias was rated as high in two out of twenty studies. Most of the studies presented baseline characteristics and outcomes appropriately.

Cyclodextrin Encapsulated pH Sensitive Dyes as Fluorescent Cellular Probes: Self-Aggregation and In Vitro Assessments

We have designed and synthesized a series of novel, supramolecular, long-lived fluorescent probes based on the host-guest inclusion complexes formation between fluorescent indolizinyl-pyridinium salts and β-cyclodextrin. Fluorescence and electrospray ionisation mass spectrometry experiments, supported by theoretical molecular docking studies, were utilized in the monitoring of the inclusion complexes formation, evidencing the appearance of corresponding 1:1 and 1:2 species. Additionally, the influence of the guest molecule over the aggregation processes of the cyclodextrin inclusion complexes was investigated by transmission electron microscopy. The absence of cytotoxicity, cellular permeability, long-lived intracellular fluorescence, and in time specific accumulation within acidic organelles identified the investigated supramolecular entities as remarkable candidates for intracellular fluorescence probes. Co-staining experiments using specific organelle markers revealed the fact that, after a 24-h incubation period, the inclusion complexes accumulate predominantly in lysosomes rather than in mitochondria. This study opens new possibilities for a broad range of fluorescent dyes with solubility and high toxicity issues, able to form inclusion complexes with β-cyclodextrin, to be tested as intracellular fluorescence probes.

Polyelectrolytic gelatin nanoparticles as a drug delivery system for the promastigote form of Leishmania amazonensis treatment

In this study, phthalocianato[bis(dimethylaminoethanoxy)] silicon (NzPC) was loaded onto gelatin nanoparticles functionalized with polyelectrolytes (polystyrene sulfonate/polyallylamine hydrochloride) by layer-by-layer (LbL) assembly for photodynamic therapy (PDT) application in promastigote form of Leishmania amazonensis treatment. The process yield, and encapsulation efficiency were 80.0% ± 1.8 and EE = 87.0% ± 1.1, respectively. The polyelectrolytic gelatin nanoparticles (PGN) had a mean diameter of 437.4 ± 72.85 nm, narrow distribution size with a polydispersity index of 0.086. The obvious switching of zeta potential indicates successful alternating deposition of the polyanion PSS and polycation PAH directly on the gelatin nanoparticles. Photosensitizer photophysical properties were shown to be preserved after gelatin nanoparticle encapsulation. The impact of the PDT in the viability and morphology of Leishmania amazonensis promastigote in culture medium was evaluated. The PGN-NzPc presented low toxicity at the dark and the PDT was capable of decreasing the viability in more than 80% in 0.1 µmol.L^-1 concentration tested. The PDT also triggered significant morphological alterations in the Leishmania promastigotes. These results reinforce the idea that the use of PGN as photosensitizers carriers is useful for PDT of Leishmania promastigotes.

Preparation and in vitro characterization of rosuvastatin calcium incorporated methyl beta cyclodextrin and Captisol® inclusion complexes

Despite being the most effective hypolipidemic agent, poor physicochemical properties of Rosuvastatin calcium (RCa) remain challenging obstacles in the development of pharmaceutical dosage forms. Inclusion complexes (ICs) of RCa with cyclodextrin (CD) derivatives; methyl-beta-cyclodextrin (M-β-CD) and sulfobutylether-beta-cyclodextrin (SBE-β-CD; Captisol^®) were formulated by kneading and freeze-drying (lyophilization) methods. Pysicochemical properties of ICs were evaluated by SEM, DSC, XRD, FT-IR, ¹H-NMR analyses. Entrapment efficiency (EE), water solubility, in vitro release analyses were also performed. Safety and efficacy of the ICs were analyzed by cytotoxicity and permeation studies on Caco-2 cell lines. Both CDs indicated A_L type phase solubility diagrams showing that [1:1] molar ratio. Apparent stability constants (K_1:1) were found to be 60.93 M^-1 for M-β-CD and 158.07 M^-1 for Captisol^®. High EE in the range of 93.50-105.40% was achieved. Molar solubility of RCa was increased 3.7- and 4.1-fold with M-β-CD and Captisol^® ICs, respectively. In vitro release analyses have indicated the equivalence of dissolution profiles for M-β-CD and Captisol^® based ICs to that of pure RCa (f₂ > 50). Cytotoxicity studies on Caco-2 cell lines have revealed the safety of ICs for oral use. Permeability studies demonstrated that selected lyophilized F6 formulation has shown the best permeation rate with P_app value of 3.08 × 10^-7 cm·s^-1. Considering greater water solubility, lower toxicity, high efficiency of complexation as well as, RCa-like permeability and in vitro release behavior at pH 6.8; Captisol^® based lyophilized F6 formulation was selected as the best IC to be used in oral dosage forms of RCa.

The Lord of the NanoRings: Cyclodextrins and the battle against SARS-CoV-2

A handful of singular structures and laws can be observed in nature. They are not always evident but, once discovered, it seems obvious how to take advantage of them. In chemistry, the discovery of reproducible patterns stimulates the imagination to develop new functional materials and technological or medical applications. Two clear examples are helical structures at different levels in biological polymers as well as ring and spherical structures of different size and composition. Rings are intuitively observed as holes able to thread elongated structures. A large number of real and fictional stories have rings as inanimate protagonists. The design, development or just discovering of a special ring has often been taken as a symbol of power or success. Several examples are the Piscatory Ring wore by the Pope of the Catholic Church, the NBA Championship ring and the One Ring created by the Dark Lord Sauron in the epic story The Lord of the Rings. In this work, we reveal the power of another extremely powerful kind of rings to fight against the pandemic which is currently affecting the whole world. These rings are as small as ~1 nm of diameter and so versatile that they are able to participate in the attack of viruses, and specifically SARS-CoV-2, in a large range of different ways. This includes the encapsulation and transport of specific drugs, as adjuvants to stabilize proteins, vaccines or other molecules involved in the infection, as cholesterol trappers to destabilize the virus envelope, as carriers for RNA therapies, as direct antiviral drugs and even to rescue blood coagulation upon heparin treatment.

“One ring to rule them all. One ring to find them. One ring to bring them all and in the darkness bind them.” J. R. R. Tolkien.

Nanotechnology as a Platform for the Development of Injectable Parenteral Formulations: A Comprehensive Review of the Know-Hows and State of the Art

Within recent decades, the development of nanotechnology has made a significant contribution to the progress of various fields of study, including the domains of medical and pharmaceutical sciences. A substantially transformed arena within the context of the latter is the development and production of various injectable parenteral formulations. Indeed, recent decades have witnessed a rapid growth of the marketed and pipeline nanotechnology-based injectable products, which is a testimony to the remarkability of the aforementioned contribution. Adjunct to the ability of nanomaterials to deliver the incorporated payloads to many different targets of interest, nanotechnology has substantially assisted to the development of many further facets of the art. Such contributions include the enhancement of the drug solubility, development of long-acting locally and systemically injectable formulations, tuning the onset of the drug’s release through the endowment of sensitivity to various internal or external stimuli, as well as adjuvancy and immune activation, which is a desirable component for injectable vaccines and immunotherapeutic formulations. The current work seeks to provide a comprehensive review of all the abovementioned contributions, along with the most recent advances made within each domain. Furthermore, recent developments within the domains of passive and active targeting will be briefly debated.

A clioquinol-containing Pluronic® F127 polymeric micelle system is effective in the treatment of visceral leishmaniasis in a murine model

A clioquinol (ICHQ)-containing Pluronic^® F127 polymeric micelle system (ICHQ/Mic) was recently shown to be effective against Leishmania amazonensis infection in a murine model. In the present study, ICHQ/Mic was tested against L. infantum infection. BALB/c mice (n = 12 per group) were infected with L. infantum stationary promastigotes through subcutaneous injection and, 45 days after challenge, received saline or were treated via the subcutaneous route with empty micelles, ICHQ or ICHQ/Mic. In addition, animals were treated with miltefosine by the oral route, as a drug control. Half of the animals were euthanized 1 and 15 days after treatment, aiming to evaluate two endpoints after therapy, when parasitological and immunological parameters were investigated. Results showed that the treatment using miltefosine, ICHQ or ICHQ/Mic induced significantly higher anti-parasite IFN-γ, IL-12, GM-CSF, nitrite and IgG2a isotype antibody levels, which were associated with low IL-4 and IL-10 production. In addition, a higher frequency of IFN-γ and TNF-α-producing CD4⁺ and CD8⁺ T-cells was found in these animals. The parasite load was evaluated in distinct organs, and results showed that the treatment using miltefosine, ICHQ or ICHQ/Mic induced significant reductions in organic parasitism in the treated and infected mice. A comparison between the treatments suggested that ICHQ/Mic was the most effective in inducing a highly polarized Th1-type response, as well as reducing the parasite load in significant levels in the treated and infected animals. Data obtained 15 days after treatment suggested maintenance of the immunological and parasitological responses. In conclusion, ICHQ/Mic could be considered in future studies for the treatment of visceral leishmaniasis.

Cyclodextrin Based Nanoparticles for Drug Delivery and Theranostics

Colloidal nanoparticulate technology has been described in the literature as a versatile drug delivery system. But it possesses some inherent lacunae in their formulation. Cyclodextrins (CDs) have been extensively reported for the solubility enhancement of poorly water-soluble drugs. The CDs can cause intervention in aspects related to nanoparticles (NPs) that include improving drug loading in nano-system, improving stability, site-specific/targeted drug delivery, improving solubility profile and absorption of the drug in nanosystem with consequent improvement in bioavailability, with the possibility of controlled release, safety and efficacy. They find application in for simultaneous diagnosis and therapeutics for better treatment procedures. The current communication is focused on the application of CDs to overcome troubles in nanoparticulate formulation and enhancement of their performance. It also envisages the theranostic aspects of CDs.

Nanocarriers for effective delivery of benznidazole and nifurtimox in the treatment of chagas disease: A review

Neglected tropical diseases (NTDs) constitute a group of infectious diseases prevalent in countries with tropical and subtropical climate that affect the poorest individuals and produce high chronic disability associated with serious problems for the health system and socioeconomic development. Chagas disease or American trypanosomiasis is included on the NTDs list. However, even though this disease affects more than 10 million people, mostly in Latin America, causing the death of over 10,000 people every year, only two drugs are approved for its treatment, benznidazole and nifurtimox. These antiparasitic agents were developed almost half a century ago and present several biopharmaceutical disadvantages such as low aqueous solubility and permeability limiting their bioavailability. In addition, both therapeutic agents are available only as tablets and a liquid pediatric formulation is still lacking. Therefore, novel pharmaceutical strategies to optimize the pharmacotherapy of Chagas disease are urgently required. In this regard, nanotechnological approaches may be a crucial alternative for the delivery of both drugs ensuring an effective pharmacotherapy although the successful bench-to-bedside translation remains a major challenge. The present work reviews in detail the formulation and in-vitro/in-vivo analysis of different nanoformulations of nifurtimox and benznidazole in order to enhance their solubility, dissolution, bioavailability and trypanocidal activity.

Anti-leishmanial Nanotherapeutics: A Current Perspective

Background:

Leishmaniasis is a dreaded disease caused by protozoan parasites belonging to the genus Leishmania which results in significant morbidity and mortality worldwide. There are no vaccines available currently for the treatment of Leishmaniasis and chemotherapy still remains the mainstay for anti-leishmanial therapeutics. However, toxicity, reduced bioavailability, high cost and chemoresistance are the principal problems which limit the use of the available drugs. In this context, anti-leishmanial nanotherapeutics may show the way for effective treatment of this dreaded disease.

Methods:

We carried out extensive literature search of bibliographic database using keywords strictly within the scope of the present study for peer reviewed research articles. We focused specifically on articles related to the application of nanotechnology in drug development, drug delivery and vaccine delivery for anti-leishmanial therapeutics.

Results:

This study shows the immense potential of the application of nanotechnology in the field of anti-leishmanial therapeutics. This will aid the targeted delivery of different drugs which is expected to increase the bioavailability, reduce toxicity and also address the problem of chemoresistance.

Conclusion:

We surmise that exciting research in the field of anti-leishmanial nanotherapeutics is already showing the promise for effective applicability. Though direct use of nanoparticles as therapeutic agents does not seem to be a good option, the application of nanotechnology in this field for vaccine development is still in its early days. The nano based drug delivery system for anti-leishmanial therapeutics has evolved considerably over the past ten years and holds the potential to drastically change the landscape of anti-leishmanial therapeutics.

Cyclodextrin⁻Drug Inclusion Complexes: In Vivo and In Vitro Approaches

This review aims to provide a critical review of the biological performance of natural and synthetic substances complexed with cyclodextrins, highlighting: (i) inclusion complexes with cyclodextrins and their biological studies in vitro and in vivo; (ii) Evaluation and comparison of the bioactive efficacy of complexed and non-complexed substances; (iii) Chemical and biological performance tests of inclusion complexes, aimed at the development of new pharmaceutical products. Based on the evidence presented in the review, it is clear that cyclodextrins play a vital role in the development of inclusion complexes which promote improvements in the chemical and biological properties of the complexed active principles, as well as providing improved solubility and aqueous stability. Although the literature shows the importance of their ability to help produce innovative biotechnological substances, we still need more studies to develop and expand their therapeutic properties. It is, therefore, very important to gather together evidence of the effectiveness of inclusion complexes with cyclodextrins in order to facilitate a better understanding of research on this topic and encourage further studies.

Mannosylated thiolated paromomycin-loaded PLGA nanoparticles for the oral therapy of visceral leishmaniasis

AIM

The present study evaluates the efficacy of paromomycin (PM)-loaded mannosylated thiomeric nanoparticles for the targeted delivery to pathological organs for the oral therapy of visceral leishmaniasis.

MATERIALS & METHODS

Mannosylated thiolated chitosan (MTC)-coated PM-loaded PLGA nanoparticles (MTC-PLGA-PM) were synthesized and evaluated for morphology, drug release, permeation enhancing and antileishmanial potential.

RESULTS

MTC-PLGA-PM were spherical in shape with a size of 391.24 ± 6.91 nm and an encapsulation efficiency of 67.16 ± 14%. Ex vivo permeation indicated 12.73-fold higher permeation of PM with MTC-PLGA-PM against the free PM. Flow cytometry indicated enhanced macrophage uptake and parasite killing in Leishmania donovani infected macrophage model. In vitro antileishmanial activity indicated 36-fold lower IC₅₀ for MTC-PLGA-PM as compared with PM. The in vivo studies indicated 3.6-fold reduced parasitic burden in the L. donovani infected BALB/c mice model.

CONCLUSION

The results encouraged the concept of MTC-PLGA-PM nanoparticles as promising strategy for visceral leishmaniasis.

Electrospinning of Cyclodextrin Functional Nanofibers for Drug Delivery Applications

Electrospun nanofibers have sparked tremendous attention in drug delivery since they can offer high specific surface area, tailored release of drugs, controlled surface chemistry for preferred protein adsorption, and tunable porosity. Several functional motifs were incorporated into electrospun nanofibers to greatly expand their drug loading capacity or to provide the sustained release of the embedded drug molecules. In this regard, cyclodextrins (CyD) are considered as ideal drug carrier molecules as they are natural, edible, and biocompatible compounds with a truncated cone-shape with a relatively hydrophobic cavity interior for complexation with hydrophobic drugs and a hydrophilic exterior to increase the water-solubility of drugs. Further, the formation of CyD-drug inclusion complexes can protect drug molecules from physiological degradation, or elimination and thus increases the stability and bioavailability of drugs, of which the release takes place with time, accompanied by fiber degradation. In this review, we summarize studies related to CyD-functional electrospun nanofibers for drug delivery applications. The review begins with an introductory description of electrospinning; the structure, properties, and toxicology of CyD; and CyD-drug complexation. Thereafter, the release of various drug molecules from CyD-functional electrospun nanofibers is provided in subsequent sections. The review concludes with a summary and outlook on material strategies.

Novel nano-sized chitosan amphotericin B formulation with considerable improvement against Leishmania major

AIM

Improvement in the treatment of Leishmania major's pathological effects through increasing the dose of amphotericin B loaded into nanochitosan.

MATERIALS & METHODS

The phase separation method was used for nanochitosan synthesis and amphotericin loading. Also a novel solvent was designed and the nanodrug efficacy was evaluated in vitro and in vivo (pathology) environments.

RESULTS

The drug loading efficiency of 90%, along with slow drug-release with cellular uptake of 98.6% was achieved. The novel solvent was composed of 10% acetic acid, and it was succeeded to dissolve AK10 mg/kg. Also, AK10 mg/kg had no side effects in in vitro and in vivo environments. In addition, the complete wound healing and parasite inhibition were achieved by using AK10 mg/kg in terms of improvement the treatment indicators.

CONCLUSION

Increasing the therapeutic dose of AK to 10 mg/kg caused the successful treatment of L. major's pathological effects in in vitro and in vivo environments.