Cyclodextrins-modified metallic nanoparticles for effective cancer therapy

Cyclodextrins as non-viral vectors in cancer theranostics: A review

Cancer ranks as the top cause of death following cardiovascular diseases. Identifying cancer patients at early stages presents significant challenges due to the asymptomatic nature of early-stage tumors. Conversely, the advancement of therapy resistance has led to a reduction in cancer treatment efficacy. Consequently, utilizing nanoparticles for the diagnosis and treatment of cancer can greatly enhance the prognosis and results for patients. CDs are recognized entities in the pharmaceutical domain and have been extensively used for therapeutic purposes in disease treatment. These non-viral vectors have shown efficacy in inhibiting both solid tumors and hematological malignancies through targeted drug delivery. CDs can enhance the administration of medications and genes in cancer treatment by ensuring their continuous release. The stimuli-responsive CDs have enhanced the targeted delivery of payloads at the tumor location, responding to the stimuli in TME such as pH, redox and light. CDs can serve as effective carriers that enhance the efficacy of phototherapy by improving the solubility and delivery of phototherapeutic agents, enabling integration with chemotherapy and immunotherapy. The administration of immunomodulators through CDs can enhance cancer immunotherapy and boost the infiltration of immune cells. Ultimately, CDs can aid in cancer diagnosis and the identification of biomarkers.

A narrative review on the use of Green synthesized metallic nanoparticles for targeted cancer therapy

Cancer is a leading cause of death worldwide. While traditional and synthetic medical therapies are in place for cancer treatment, their effectiveness is hindered by various limitations, such as toxic side effects, limited availability, and high costs. In recent years, a promising alternative approach has emerged in the form of green-synthesized metallic nanoparticles (MNPs), which offer targeted cancer therapy. These nanoparticles (NPs) have garnered significant attention from cancer researchers owing to their natural or surface-induced anticancer properties, versatility of metals as agents, and eco-friendly nature. This approach may positively impact healthy cells surrounding the cancerous cells. Green-synthesized MNPs have gained popularity in cancer management because of their ease of handling in the laboratory and the affordability of starting materials compared to synthetic methods. This review analyzes green-synthesized MNPs for targeted cancer therapy, highlighting tumor-targeting strategies, synthesis methods, and clinical challenges. Unlike general reviews, it compares plant-, microbial-, and enzyme-mediated synthesis approaches, emphasizing their impact on nanoparticle stability, functionalization, and interactions with the tumor microenvironment for enhanced therapeutic efficacy.

Cyclodextrin as a singular oligosaccharide: Recent advances of health benefit and in food applications

Cyclodextrins (CDs) are cyclic oligosaccharides derived from the enzymatic degradation of starch. Their distinct molecular shape, which resembles a truncated cone with a hydrophobic interior and a hydrophilic outer surface, enables the formation of inclusion complexes via host-guest interactions. These complexes facilitate beneficial modifications such as enhancing the solubility and stabilizing unstable guest molecules. By forming inclusion complexes with bioactive components and drugs, CDs can increase the bioavailability of these compounds, providing benefits in the treatment of various diseases. Particularly, β-CD can form complexes by trapping hydrophobic molecules such as cholesterol in its hydrophobic cavity. Moreover, CDs are considered significant soluble dietary fibers due to their resistance against human digestive enzymes and their utilization by intestinal microbiota. All these features suggest that CDs could encapsulate phospholipids and food components, potentially improving or preventing metabolic diseases such as cardiovascular diseases, diabetes, and neurological disorders by blocking the absorption of carbohydrates, fats, and cholesterol. This review seeks to investigate the clinical effects and mechanisms of action considering all their potential properties and their relevance to health by utilizing in vivo, in vitro, animal, and human studies.

Engineering dendritic cell biomimetic membrane as a delivery system for tumor targeted therapy

Targeted immunotherapies make substantial strides in clinical cancer care due to their ability to counteract the tumor's capacity to suppress immune responses. Advances in biomimetic technology with minimally immunogenic and highly targeted, are addressing issues of targeted drug delivery and disrupting the tumor's immunosuppressive environment to trigger immune activation. Specifically, the use of dendritic cell (DC) membranes to coat nanoparticles ensures targeted delivery due to DC's unique ability to activate naive T cells, spotlighting their role in immunotherapy aimed at disrupting the tumor microenvironment. The potential of DC's biomimetic membrane to mediate immune activation and target tumors is gaining momentum, enhancing the effectiveness of cancer treatments in conjunction with other immune responses. This review delves into the methodologies behind crafting DC membranes and the fusion of dendritic and tumor cell membranes for encapsulating therapeutic nanoparticles. It explores their applications and recent advancements in combating cancer, offering an all-encompassing perspective on DC biomimetic nanosystems, immunotherapy driven by antigen presentation, and the collaborative efforts of drug delivery in chemotherapy and photodynamic therapies. Current evidence shows promise in augmenting combined therapeutic approaches for cancer treatment and holds translational potential for various cancer treatments in a clinical setting.

Cyclodextrin metal-organic framework@SiO2 nanocomposites for poorly soluble drug loading and release

The development of non-toxic drug carrier materials with high loading capacity, sustained release properties, stability, and biocompatibility holds significant medical value and potential for loading and releasing poorly soluble drugs. In this study, we synthesized a biocompatible, non-toxic, environmentally friendly CD-MOF porous material with high specific surface area and tunable structure. By incorporating SiO2 to enhance the stability of MOF materials, the synthesized CD-MOF@SiO2 material shows promising applications in drug delivery. The obtained CD-MOF@SiO2 nanocomposite was utilized as a carrier for the poorly soluble drug, folic acid. Characterization of the drug-loaded composite before and after drug loading was performed using scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, N2 adsorption-desorption, and X-ray diffraction analyses, showing improved stability as indicated by thermogravimetric analysis and derivative thermogravimetry data. UV spectrophotometry was used to investigate the loading and sustained release of folic acid under different conditions in PBS buffer, demonstrating that the well-structured CD-MOF@SiO2 material exhibits high drug loading and controllable release properties. The CD-MOF@SiO2 achieved a high drug loading efficiency (166.78%) and encapsulation rate (83.39%) for folic acid, leading to a significant increase in apparent solubility from 1.6 μg mL-1 in its free form to 21.74 mg mL-1, a 13 588-fold expansion. This work presents a novel, efficient, and highly valuable approach for the development of carrier materials for loading and releasing poorly soluble drugs.

β-Glucan-A promising immunocyte-targeting drug delivery vehicle: Superiority, applications and future prospects

Drug delivery technologies that could convert promising therapeutics into successful therapies have been under broad research for many years. Recently, β-glucans, natural-occurring polysaccharides extracted from many organism species such as yeast, fungi and bacteria, have attracted increasing attention to serve as drug delivery carriers. With their unique structure and innate immunocompetence, β-glucans are considered as promising carriers for targeting delivery especially when applied in the vaccine construction and oral administration of therapeutic agents. In this review, we focus on three types of β-glucans applied in the drug delivery system including yeast β-glucan, Schizophyllan and curdlan, highlighting the benefits of β-glucan based delivery system. We summarize how β-glucans as delivery vehicles have aided various therapeutics ranging from macromolecules including proteins, peptides and nucleic acids to small molecular drugs to reach desired cells or organs in terms of loading strategies. We also outline the challenges and future directions for developing the next generation of β-glucan based delivery systems.

Advancements in application of chitosan and cyclodextrins in biomedicine and pharmaceutics: recent progress and future trends

The global community is faced with numerous health concerns such as cancer, cardiovascular and neurological diseases, diabetes, joint pain, osteoporosis, among others. With the advancement of research in the fields of materials chemistry and medicine, pharmaceutical technology and biomedical analysis have entered a new stage of development. The utilization of natural oligosaccharides and polysaccharides in pharmaceutical/biomedical studies has gained significant attention. Over the past decade, several studies have shown that chitosan and cyclodextrin have promising biomedical implications in background analysis, ongoing development, and critical applications in biomedical and pharmaceutical research fields. This review introduces different types of saccharides/natural biopolymers such as chitosan and cyclodextrin and discusses their wide-ranging applications in the biomedical/pharmaceutical research area. Recent research advances in pharmaceutics and drug delivery based on cyclodextrin, and their response to smart stimuli, as well as the biological functions of cyclodextrin and chitosan, such as the immunomodulatory effects, antioxidant, and antibacterial properties, have also been discussed, along with their applications in tissue engineering, wound dressing, and drug delivery systems. Finally, the innovative applications of chitosan and cyclodextrin in the pharmaceutical/biomedicine were reviewed, and current challenges, research/technological gaps, and future development opportunities were surveyed.

Multifunctionality of cyclodextrin-based polymeric nanoparticulate delivery systems for chemotherapeutics, combination therapy, and theranostics

As cancer being the most difficult disease to treat, different kinds of medications and therapeutic approaches have been prominently developed by scientists. For certain families of drugs, such as immuno-therapeutics or antibody-drug conjugates, efficient delivery systems are required during administration to protect the drugs from chemical degradation or biological inactivation. Delivery systems with the ability to carry different therapeutics or diagnostic agents or both, hold promising potential to tackle the abnormalities behind cancer. In this context, this review provides updated insights on how cyclodextrin-based polymeric nanosystems have become an effective treatment approach against cancer. Cyclodextrins (CDs) are natural oligosaccharides that are famously exploited in pharmaceutical research due to their exceptional quality of entrapping water-insoluble molecules inside their hydrophobic core and providing enhanced solubility with the help of their hydrophilic exterior. Combining the properties of CDs with polymeric nanoparticles (PNPs) brings out excellent versatile and tunable profiles, thanks to the submicron-sized PNPs. By introducing the significance of CD as a delivery system, a collective discussion on different binding approaches and release mechanisms of CD-drug complexation, followed by their characterization studies has been done in this review. Further, in light of recent studies, the article majorly focuses on conveying how promoting CD to a polymeric and nanoscale elevates the multifunctional advantages against cancer that can be successfully applied in combination therapy and theranostics. Moreover, CD-based delivery systems including CALAA-01, CRLX101, and CRLX301, have demonstrated improved tumor targeting, reduced side effects, and prolonged drug release in preclinical studies and clinical trials.

Microencapsulation for Pharmaceutical Applications: A Review

In order to improve bioavailability, stability, control release, and target delivery of active pharmaceutical ingredients (APIs), as well as to mask their bitter taste, to increase their efficacy, and to minimize their side effects, a variety of microencapsulation (including nanoencapsulation, particle size <100 nm) technologies have been widely used in the pharmaceutical industry. Commonly used microencapsulation technologies are emulsion, coacervation, extrusion, spray drying, freeze-drying, molecular inclusion, microbubbles and microsponge, fluidized bed coating, supercritical fluid encapsulation, electro spinning/spray, and polymerization. In this review, APIs are categorized by their molecular complexity: small APIs (compounds with low molecular weight, like Aspirin, Ibuprofen, and Cannabidiol), medium APIs (compounds with medium molecular weight like insulin, peptides, and nucleic acids), and living microorganisms (such as probiotics, bacteria, and bacteriophages). This article provides an overview of these microencapsulation technologies including their processes, matrix, and their recent applications in microencapsulation of APIs. Furthermore, the advantages and disadvantages of these common microencapsulation technologies in terms of improving the efficacy of APIs for pharmaceutical treatments are comprehensively analyzed. The objective is to summarize the most recent progresses on microencapsulation of APIs for enhancing their bioavailability, control release, target delivery, masking their bitter taste and stability, and thus increasing their efficacy and minimizing their side effects. At the end, future perspectives on microencapsulation for pharmaceutical applications are highlighted.

The quest for nanoparticle-powered vaccines in cancer immunotherapy

Despite recent advancements in cancer treatment, this disease still poses a serious threat to public health. Vaccines play an important role in preventing illness by preparing the body's adaptive and innate immune responses to combat diseases. As our understanding of malignancies and their connection to the immune system improves, there has been a growing interest in priming the immune system to fight malignancies more effectively and comprehensively. One promising approach involves utilizing nanoparticle systems for antigen delivery, which has been shown to potentiate immune responses as vaccines and/or adjuvants. In this review, we comprehensively summarized the immunological mechanisms of cancer vaccines while focusing specifically on the recent applications of various types of nanoparticles in the field of cancer immunotherapy. By exploring these recent breakthroughs, we hope to identify significant challenges and obstacles in making nanoparticle-based vaccines and adjuvants feasible for clinical application. This review serves to assess recent breakthroughs in nanoparticle-based cancer vaccinations and shed light on their prospects and potential barriers. By doing so, we aim to inspire future immunotherapies for cancer that harness the potential of nanotechnology to deliver more effective and targeted treatments.

Anti-CD64 Antibody-Conjugated PLGA Nanoparticles Containing Methotrexate and Gold for Theranostics Application in Rheumatoid Arthritis

Rheumatoid arthritis, an autoimmune disorder, exerts a considerable effect on quality of life. The inflammatory mechanism involved in rheumatoid arthritis is not clearly known, and therefore the need to develop effective medicines as well as new methods for early detection is a challenge. In this study, we developed PLGA nanoparticles containing gold and methotrexate in core and anti-CD64 antibody conjugated to nanoparticle surface via coupling process. The nanoparticles were examined for their surface morphology using SEM and TEM. The mean particle size, zeta potential, and PDI values of nanoparticles were 413.6 ± 2.89 nm, -10.12 ± 2.12 mV, and 0.23 ± 0.04, respectively, indicating good stability and particle homogeneity. In vitro drug release revealed a controlled release pattern with 93.44 ± 1.60% up to 72 h of release in the presence of pH 5.8, indicating the influence of pH and NIR on drug release. In vivo results on adjuvant-induced arthritis on Wistar rats indicated that animals receiving antibody-conjugated nanoparticles showed improvement in clinical indices and arthritic score as compared to non-conjugated nanoparticles and free drugs. This innovative drug delivery system will be an excellent strategy to maximize therapeutic effectiveness by limiting dosage-related side effects.

Opportunities and challenges in enhancing the bioavailability and bioactivity of dietary flavonoids: A novel delivery system perspective

Flavonoids have multiple favorable bioactivities including antioxidant, anti-inflammatory, and antitumor. Currently, flavonoid-containing dietary supplements are widely tested in clinical trials for the prevention and/or treatment of multiple diseases. However, the clinical application of flavonoids is largely compromised by their low bioavailability and bioactivity, probably due to their poor aqueous solubility, intensive metabolism, and low systemic absorption. Therefore, formulating flavonoids into novel delivery systems is a promising approach for overcoming these drawbacks. In this review, we highlight the opportunities and challenges in the clinical use of dietary flavonoids from the perspective of novel delivery systems. First, the classification, sources, and bioactivity of dietary flavonoids are described. Second, the progress of clinical research on flavonoid-based dietary supplements is systematically summarized. Finally, novel delivery systems developed to improve the bioavailability and bioactivity of flavonoids are discussed in detail to broaden the clinical application of dietary flavonoids.

Metal nanoparticles and carbohydrate polymers team up to improve biomedical outcomes

The convergence of carbohydrate polymers and metal nanoparticles (MNPs) holds great promise for biomedical applications. Researchers aim to exploit the capability of carbohydrate matrices to modulate the physicochemical properties of MNPs, promote their therapeutic efficiency, improve targeted drug delivery, and enhance their biocompatibility. Therefore, understanding various attributes of both carbohydrates and MNPs is the key to harnessing them for biomedical applications. The many distinct types of carbohydrate-MNP systems confer unique capabilities for drug delivery, wound healing, tissue engineering, cancer treatment, and even food packaging. Here, we introduce distinct physicochemical/biological properties of carbohydrates and MNPs, and discuss their potentials and shortcomings (alone and in combination) for biomedical applications. We then offer an overview on carbohydrate-MNP systems and how they can be utilized to improve biomedical outcomes. Last but not least, future perspectives toward the application of such systems are highlighted.

Supramolecular host-guest nanosystems for overcoming cancer drug resistance

Cancer drug resistance has become one of the main challenges for the failure of chemotherapy, greatly limiting the selection and use of anticancer drugs and dashing the hopes of cancer patients. The emergence of supramolecular host-guest nanosystems has brought the field of supramolecular chemistry into the nanoworld, providing a potential solution to this challenge. Compared with conventional chemotherapeutic platforms, supramolecular host-guest nanosystems can reverse cancer drug resistance by increasing drug uptake, reducing drug efflux, activating drugs, and inhibiting DNA repair. Herein, we summarize the research progress of supramolecular host-guest nanosystems for overcoming cancer drug resistance and discuss the future research direction in this field. It is hoped that this review will provide more positive references for overcoming cancer drug resistance and promoting the development of supramolecular host-guest nanosystems.

Biopharmaceutical and nanotoxicological aspects of cyclodextrins for non-invasive topical treatments: A critical review

Cyclodextrins are nanometric cyclic oligosaccharides with amphiphilic characteristics that increase the stability of drugs in pharmaceutical forms and bioavailability, in addition to protecting them against oxidation and UV radiation. Some of their characteristics are low toxicity, biodegradability, and biocompatibility. They are divided into α-, β-, and γ-cyclodextrins, each with its own particularities. They can undergo surface modifications to improve their performances. Furthermore, their drug inclusion complexes can be made by various methods, including lyophilization, spray drying, magnetic stirring, kneading, and others. Cyclodextrins can solve several problems in drug stability when incorporated into dosage forms (including tablets, gels, films, nanoparticles, and suppositories) and allow better topical biological effects of drugs at administration sites such as skin, eyeballs, and oral, nasal, vaginal, and rectal cavities. However, as they are nanostructured systems and some of them can cause mild toxicity depending on the application site, they must be evaluated for their nanotoxicology and nanosafety aspects. Moreover, there is evidence that they can cause severe ototoxicity, killing cells from the ear canal even when applied by other administration routes. Therefore, they should be avoided in otologic administration and should have their permeation/penetration profiles and the in vivo hearing system integrity evaluated to certify that they will be safe and will not cause hearing loss.

Tissue-Engineered Nanomaterials Play Diverse Roles in Bone Injury Repair

Nanomaterials with bone-mimicking characteristics and easily internalized by the cell could create suitable microenvironments in which to regulate the therapeutic effects of bone regeneration. This review provides an overview of the current state-of-the-art research in developing and using nanomaterials for better bone injury repair. First, an overview of the hierarchical architecture from the macroscale to the nanoscale of natural bone is presented, as these bone tissue microstructures and compositions are the basis for constructing bone substitutes. Next, urgent clinical issues associated with bone injury that require resolution and the potential of nanomaterials to overcome them are discussed. Finally, nanomaterials are classified as inorganic or organic based on their chemical properties. Their basic characteristics and the results of related bone engineering studies are described. This review describes theoretical and technical bases for the development of innovative methods for repairing damaged bone and should inspire therapeutic strategies with potential for clinical applications.

Recent progress in nanocarrier-based drug delivery systems for antitumour metastasis

Tumour metastasis is one of the major factors leading to poor prognosis as well as lower survival among cancer patients. A number of studies investigating the inhibition of tumour metastasis have been conducted. It is difficult to achieve satisfactory results with surgery alone for distant metastatic tumours, and chemotherapy can boost the healing rate and prognosis of patients. However, the poor therapeutic efficacy of chemotherapy drugs due to their low solubility, lack of tumour targeting, instability in vivo, high toxicity and multidrug resistance hinder their application. Immunotherapy is beneficial to the treatment of metastatic cancers, but it also has disadvantages such as adverse reactions and acquired resistance. Fortunately, delivery of chemotherapeutic drugs with nanocarriers can reduce systemic reactions caused by chemotherapeutic agents and inhibit metastasis. This review discusses the underlying mechanisms of metastasis, therapeutic approaches for antitumour metastasis, the advantages of nanodrug delivery systems and their application in reducing metastasis.

Cyclodextrins as eminent constituents in nanoarchitectonics for drug delivery systems

Cyclodextrins have been widely employed for drug delivery systems (DDSs) in which drugs are selectively delivered to a target site in the body. Recent interest has been focused on the construction of cyclodextrin-based nanoarchitectures that show sophisticated DDS functions. These nanoarchitectures are precisely fabricated based on three important features of cyclodextrins, namely (1) the preorganized three-dimensional molecular structure of nanometer size, (2) the easy chemical modification to introduce functional groups, and (3) the formation of dynamic inclusion complexes with various guests in water. With the use of photoirradiation, drugs are released from cyclodextrin-based nanoarchitectures at designated timing. Alternatively, therapeutic nucleic acids are stably protected in the nanoarchitectures and delivered to the target site. The efficient delivery of the CRISPR-Cas9 system for gene editing was also successful. Even more complicated nanoarchitectures can be designed for sophisticated DDSs. Cyclodextrin-based nanoarchitectures are highly promising for future applications in medicine, pharmaceutics, and other relevant fields.

Applications of Synthetic Receptors in Bioanalysis and Drug Transport

Synthetic receptors are powerful tools for molecular recognition. They can bind to guests with high selectivity and affinity, and their structures are tunable and diversified. These features, plus the relatively low cost and high simplicity in synthesis and modification, support the feasibility of array-based molecular analysis with synthetic receptors for improved selectivity in the recognition of a wide range of targets. More attractively, host-guest interaction is reversible and guest displacement allows biocompatible and gentle release of the host-bound molecules, simplifying the stimulation designs needed to control analyte sensing, enrichment, and transportation. Here, we highlight a few recent advancements in using synthetic receptors for molecular analysis and manipulation, with the focus on macrocyclic receptors and their applications in displacement sensing, separation, imaging, and drug transport.

Applications of Various Types of Nanomaterials for the Treatment of Neurological Disorders

Neurological disorders (NDs) are recognized as one of the major health concerns globally. According to the World Health Organization (WHO), neurological disorders are one of the main causes of mortality worldwide. Neurological disorders include Alzheimer’s disease, Parkinson′s disease, Huntington′s disease, Amyotrophic lateral sclerosis, Frontotemporal dementia, Prion disease, Brain tumor, Spinal cord injury, and Stroke. These diseases are considered incurable diseases because no specific therapies are available to cross the blood-brain barrier (BBB) and reach the brain in a significant amount for the pharmacological effect in the brain. There is a need for the development of strategies that can improve the efficacy of drugs and circumvent BBB. One of the promising approaches is the use of different types of nano-scale materials. These nano-based drugs have the ability to increase the therapeutic effect, reduce toxicity, exhibit good stability, targeted delivery, and drug loading capacity. Different types and shapes of nanomaterials have been widely used for the treatment of neurological disorders, including quantum dots, dendrimers, metallic nanoparticles, polymeric nanoparticles, carbon nanotubes, liposomes, and micelles. These nanoparticles have unique characteristics, including sensitivity, selectivity, and the ability to cross the BBB when used in nano-sized particles, and are widely used for imaging studies and treatment of NDs. In this review, we briefly summarized the recent literature on the use of various nanomaterials and their mechanism of action for the treatment of various types of neurological disorders.

Implementation of Water-Soluble Cyclodextrin-Based Polymers in Biomedical Applications: How Far are we?

Cyclodextrin-based polymers can be prepared starting from the naturally occurring monomers following green and low-cost procedures. They can be selectively derivatized pre- or post-polymerization allowing to fine-tune functionalities of ad hoc customized polymers. Preparation nowadays has reached the 100 g scale thanks also to the interest of industries in these extremely versatile compounds. During the last 15 years these macromolecules have been the object of intense investigations in view of possible biomedical applications as the ultimate goal and large amounts of scientific data are now available. Compared to their monomeric models, already used in the formulation of various therapeutic agents, they display superior behavior in terms of their solubility in water and solubilizing power towards drugs incompatible with biological fluids. Moreover, they allow the combination of more than one type of therapeutic agent in the polymeric system. In this review we provide a complete state-of-the-art on the knowledge and potentialities of water-soluble cyclodextrin-based polymers as therapeutic agents as well as carrier systems for different types of therapeutics to implement combination therapy. Finally, we give a perspective on their assets for innovation in disease treatment as well as their limits that still need to be addressed. This article is protected by copyright. All rights reserved.

Recent Developments in Metallic Nanomaterials for Cancer Therapy, Diagnosing and Imaging Applications

Cancer continues to represent a global health concern, imposing an ongoing need to research for better treatment alternatives. In this context, nanomedicine seems to be the solution to existing problems, bringing unprecedented results in various biomedical applications, including cancer therapy, diagnosing, and imaging. As numerous studies have uncovered the advantageous properties of various nanoscale metals, this review aims to present metal-based nanoparticles that are most frequently employed for cancer applications. This paper follows the description of relevant nanoparticles made of metals, metal derivatives, hybrids, and alloys, further discussing in more detail their potential applications in cancer management, ranging from the delivery of chemotherapeutics, vaccines, and genes to ablative hyperthermia therapies and theranostic platforms.

Opportunities and Challenges of Nanoparticles in Digestive Tumours as Anti-Angiogenic Therapies

Digestive tumours, a common kind of malignancy worldwide, have recently led to the most tumour-related deaths. Angiogenesis, the process of forming novel blood vessels from pre-existing vessels, is involved in various physiological and pathological processes in the body. Many studies suggest that abnormal angiogenesis plays an important role in the growth, progression, and metastasis of digestive tumours. Therefore, anti-angiogenic therapy is considered a promising target for improving therapeutic efficacy. Traditional strategies such as bevacizumab and regorafenib can target and block the activity of proangiogenic factors to treat digestive tumours. However, due to resistance and some limitations, such as poor pharmacokinetics, their efficacy is not always satisfactory. In recent years, nanotechnology-based anti-angiogenic therapies have emerged as a new way to treat digestive tumours. Compared with commonly used drugs, nanoparticles show great potential in tumour targeted delivery, controlled drug release, prolonged cycle time, and increased drug bioavailability. Therefore, anti-angiogenic nanoparticles may be an effective complementary therapy to treat digestive tumours. In this review, we outline the different mechanisms of angiogenesis, the effects of nanoparticles on angiogenesis, and their biomedical applications in various kinds of digestive tumours. In addition, the opportunities and challenges are briefly discussed.

Design, Synthesis and Evaluation of Novel Antimicrobial Polymers Based on the Inclusion of Polyethylene Glycol/TiO2 Nanocomposites in Cyclodextrin as Drug Carriers for Sulfaguanidine

Polymers and their composites have recently attracted attention in both pharmaceutical and biomedical applications. Polyethylene glycol (PEG) is a versatile polymer extensively used in medicine. Herein, three novel PEG-based polymers that are pseudopolyrotaxane (PEG/α-CD) (1), titania–nanocomposite (PEG/TiO₂NPs) (2), and pseudopolyrotaxane–titania–nanocomposite (PEG/α-CD/TiO₂NPs) (3), were synthesized and characterized. The chemical structure, surface morphology, and optical properties of the newly materials were examined by FT-IR, ¹H-NMR, SEM, and UV–Vis., respectively. The prepared polymers were used as drug carriers of sulfaguanidine as PEG/α-CD/Drug (4), PEG/TiO₂NPs/Drug (5), and PEG/α-CD/TiO₂NPs/Drug (6). The influence of these drug-carrying formulations on the physical and chemical characteristics of sulfaguanidine including pharmacokinetic response, solubility, and tissue penetration was explored. Evaluation of the antibacterial and antibiofilm effect of sulfaguanidine was tested before and after loading onto the prepared polymers against some Gram-negative and positive bacteria (E. coli, Pseudomonas aeruginosa, and Staphylococcus aureus (MRSA)), as well. The results of this work turned out to be very promising as they confirmed that loading sulfaguanidine to the newly designed polymers not only showed superior antibacterial and antibiofilm efficacy compared to the pure drug, but also modified the properties of the sulfaguanidine drug itself.

Entropy Effects in Intermolecular Associations of Crown-Ethers and Cyclodextrins with Amino Acids in Aqueous and in Non-Aqueous Media

The analysis of the ratios of entropy and enthalpy characteristics and their contributions to the change in the Gibbs energy of intermolecular interactions of crown ethers and cyclodextrins with amino acids is carried out. Two different types of macrocycles were chosen for examination: crown ethers with a hydrophilic interior and cyclodextrins with a hydrophobic inner cavity and a hydrophilic exterior. The thermodynamics of complex formation of crown ethers and cyclodextrins with amino acids in water and aqueous-organic solvents of variable composition was examined. The contributions of the entropy solvation of complexes of 18-crown-6 with glycine, alanine, phenylalanine to the change in the entropy of complexation in water-ethanol and water-dimethyl sulfoxide solvents was calculated and analyzed. It was found that the ratios of the entropy and enthalpy solvation of the reagents for these systems have similar trends when moving from water to aqueous-organic mixtures. The relationship between the thermodynamic characteristics and structural features of the complexation processes between cyclodextrins and amino acids has been established. The thermodynamic enthalpy–entropy compensation effect was revealed, and its features for complexation of cyclodextrins and 18-crown-6 were considered. It was concluded that, based on the thermodynamic parameters of molecular complexation, one could judge the mode of the formation of complexes, the main driving forces of the interactions, and the degree of desolvation.

Cyclodextrin-Modified Nanomaterials for Drug Delivery: Classification and Advances in Controlled Release and Bioavailability

In drug delivery, one widely used way of overcoming the biopharmaceutical problems present in several active pharmaceutical ingredients, such as poor aqueous solubility, early instability, and low bioavailability, is the formation of inclusion compounds with cyclodextrins (CD). In recent years, the use of CD derivatives in combination with nanomaterials has shown to be a promising strategy for formulating new, optimized systems. The goals of this review are to give in-depth knowledge and critical appraisal of the main CD-modified or CD-based nanomaterials for drug delivery, such as lipid-based nanocarriers, natural and synthetic polymeric nanocarriers, nanosponges, graphene derivatives, mesoporous silica nanoparticles, plasmonic and magnetic nanoparticles, quantum dots and other miscellaneous systems such as nanovalves, metal-organic frameworks, Janus nanoparticles, and nanofibers. Special attention is given to nanosystems that achieve controlled drug release and increase their bioavailability during in vivo studies.

The Combination of Solid-State Chemistry and Medicinal Chemistry as the Basis for the Synthesis of Theranostics Platforms

This review presents the main patterns of synthesis for theranostics platforms. We examine various approaches to the interpretation of theranostics, statistics of publications drawn from the PubMed database, and the solid-state and medicinal chemistry methods used for the formation of nanotheranostic objects. We highlight and analyze chemical methods for the modification of nanoparticles, synthesis of spacers with functional end-groups, and the immobilization of medicinal substances and fluorophores. An overview of the modern solutions applied in various fields of medicine is provided, along with an outline of specific examples and an analysis of modern trends and development areas of theranostics as a part of personalized medicine.