Dextran conjugates in drug delivery

Applications of polysaccharides in enzyme-triggered oral colon-specific drug delivery systems: A review

Enzyme-triggered oral colon-specific drug delivery system (EtOCDDS1) can withstand the harsh stomach and small intestine environments, releasing encapsulated drugs selectively in the colon in response to colonic microflora, exerting local or systematic therapeutic effects. EtOCDDS boasts high colon targetability, enhanced drug bioavailability, and reduced systemic side effects. Polysaccharides are extensively used in enzyme-triggered oral colon-specific drug delivery systems, and its colon targetability has been widely confirmed, as their properties meet the demand of EtOCDDS. Polysaccharides, known for their high safety and excellent biocompatibility, feature modifiable structures. Some remain undigested in the stomach and small intestine, whether in their natural state or after modifications, and are exclusively broken down by colon-resident microbiota. Such characteristics make them ideal materials for EtOCDDS. This article reviews the design principles of EtOCDDS as well as commonly used polysaccharides and their characteristics, modifications, applications and specific mechanism for colon targeting. The article concludes by summarizing the limitations and potential of ETOCDDS to stimulate the development of innovative design approaches.

Liver-Targeted Delivery Based on Prodrug: Passive and Active Approaches

BACKGROUND

The liver, a central organ in human metabolism, is often the primary target for drugs. However, conditions such as viral hepatitis, cirrhosis, non-alcoholic fatty liver disease (NAFLD), and hepatocellular carcinoma (HCC) present substantial health challenges worldwide. Existing treatments, which suffer from the non-specific distribution of drugs, frequently fail to achieve desired efficacy and safety, risking unnecessary liver harm and systemic side effects.

PURPOSE

The aim of this review is to synthesize the latest progress in the design of liver-targeted prodrugs, with a focus on passive and active targeting strategies, providing new insights into the development of liver-targeted therapeutic approaches.

METHODS

This study conducted an extensive literature search through databases like Google Scholar, PubMed, Web of Science, and China National Knowledge Infrastructure (CNKI), systematically collecting and selecting recent research on liver-targeted prodrugs. The focus was on targeting mechanisms, including the Enhanced Permeability and Retention (EPR) effect, the unique microenvironment of liver cancer, and active targeting through specific transporters and receptors.

RESULTS

Active targeting strategies achieve precise drug delivery by binding specific ligands to liver surface receptors. Passive targeting takes advantage of the EPR effect and tumor characteristics to enrich drugs in liver tumors. The review details successful cases of using small molecule ligands, peptides, antibodies and nanoparticles as drug carriers.

CONCLUSION

Liver-targeted prodrug strategies show great potential in enhancing the efficacy of drug treatment and reducing side effects for liver diseases. Future research should balance the advantages and limitations of both targeting strategies, focusing on optimizing drug design and targeting efficiency, especially for clinical application. In-depth research on liver-specific receptors and the development of innovative targeting molecules are crucial for advancing the field of liver-targeted prodrugs.

Glycan-based scaffolds and nanoparticles as drug delivery system in cancer therapy

Glycan-based scaffolds are unique in their high specificity, versatility, low immunogenicity, and ability to mimic natural carbohydrates, making them attractive candidates for use in cancer treatment. These scaffolds are made up of glycans, which are biopolymers with well biocompatibility in the human body that can be used for drug delivery. The versatility of glycan-based scaffolds allows for the modulation of drug activity and targeted delivery to specific cells or tissues, which increases the potency of drugs and reduces side effects. Despite their promise, there are still technical challenges in the design and production of glycan-based scaffolds, as well as limitations in their therapeutic efficacy and specificity.

Focused Ultrasound as a Novel Non-Invasive Method for the Delivery of Gold Nanoparticles to Retinal Ganglion Cells

Purpose

The blood-retinal barrier (BRB) restricts the delivery of intravenous therapeutics to the retina, necessitating innovative approaches for treating retinal disorders. This study sought to explore the potential of focused ultrasound (FUS) to non-invasively deliver intravenously administered gold nanoparticles (AuNPs) across the BRB. FUS-BRB modulation can offer a novel method for targeted retinal therapy.

Methods

AuNPs of different sizes and shapes were characterized, and FUS parameters were optimized to permeate the BRB without causing retinal damage in a rodent model. The delivery of 70-kDa dextran and AuNPs to the retinal ganglion cell (RGC) layer was visualized using confocal and two-photon microscopy, respectively. Histological and statistical analyses were conducted to assess the effectiveness and safety of the procedure.

Results

FUS-BRB modulation resulted in the delivery of dextran and AuNPs to the RGC and inner nuclear layer. Smaller AuNPs reached the retinal layers to a greater extent than larger ones. The delivery of dextran and AuNPs across the BRB with FUS was achieved without significant retinal damage.

Conclusions

This investigation provides the first evidence, to our knowledge, of FUS-mediated AuNP delivery across the BRB, establishing a foundation for a targeted and non-invasive approach to retinal treatment. The results contribute to developing promising non-invasive therapeutic strategies in ophthalmology to treat retinal diseases.

Translational Relevance

Modifying the BRB with ultrasound offers a targeted and non-invasive delivery strategy of intravenous therapeutics to the retina.

A review of the current state of natural biomaterials in wound healing applications

Skin, the largest biological organ, consists of three main parts: the epidermis, dermis, and subcutaneous tissue. Wounds are abnormal wounds in various forms, such as lacerations, burns, chronic wounds, diabetic wounds, acute wounds, and fractures. The wound healing process is dynamic, complex, and lengthy in four stages involving cells, macrophages, and growth factors. Wound dressing refers to a substance that covers the surface of a wound to prevent infection and secondary damage. Biomaterials applied in wound management have advanced significantly. Natural biomaterials are increasingly used due to their advantages including biomimicry of ECM, convenient accessibility, and involvement in native wound healing. However, there are still limitations such as low mechanical properties and expensive extraction methods. Therefore, their combination with synthetic biomaterials and/or adding bioactive agents has become an option for researchers in this field. In the present study, the stages of natural wound healing and the effect of biomaterials on its direction, type, and level will be investigated. Then, different types of polysaccharides and proteins were selected as desirable natural biomaterials, polymers as synthetic biomaterials with variable and suitable properties, and bioactive agents as effective additives. In the following, the structure of selected biomaterials, their extraction and production methods, their participation in wound healing, and quality control techniques of biomaterials-based wound dressings will be discussed.

Polysaccharides as a Hydrophilic Building Block of Amphiphilic Block Copolymers for the Conception of Nanocarriers

Polysaccharides are gaining increasing attention for their relevance in the production of sustainable materials. In the domain of biomaterials, polysaccharides play an important role as hydrophilic components in the design of amphiphilic block copolymers for the development of drug delivery systems, in particular nanocarriers due to their outstanding biocompatibility, biodegradability, and structural versatility. The presence of a reducing end in polysaccharide chains allows for the synthesis of polysaccharide-based block copolymers. Compared with polysaccharide-based graft copolymers, the structure of block copolymers can be more precisely controlled. In this review, the synthesis methods of polysaccharide-based amphiphilic block copolymers are discussed in detail, taking into consideration the structural characteristics of polysaccharides. Various synthetic approaches, including reductive amination, oxime ligation, and other chain-end modification reactions, are explored. This review also focuses on the advantages of polysaccharides as hydrophilic blocks in polymeric nanocarriers. The structure and unique properties of different polysaccharides such as cellulose, hyaluronic acid, chitosan, alginate, and dextran are described along with examples of their applications as hydrophilic segments in the synthesis of amphiphilic copolymers to construct nanocarriers for sustained drug delivery.

Emerging natural polymer-based architectured nanotherapeutics for the treatment of cancer

The field of cancer therapy is advancing rapidly, placing a crucial emphasis on innovative drug delivery systems. The increasing global impact of cancer highlights the need for creative therapeutic strategies. Natural polymer-based nanotherapeutics have emerged as a captivating avenue in this pursuit, drawing substantial attention due to their inherent attributes. These attributes include biodegradability, biocompatibility, negligible toxicity, extended circulation time, and a wide range of therapeutic payloads. The unique size, shape, and morphological characteristics of these systems facilitate profound tissue penetration, complementing active and passive targeting strategies. Moreover, these nanotherapeutics exploit specific cellular and subcellular trafficking pathways, providing precise control over drug release kinetics. This comprehensive review emphasizes the utilization of naturally occurring polymers such as polysaccharides (e.g., chitosan, hyaluronic acid, alginates, dextran, and cyclodextrin) and protein-based polymers (e.g., ferritin, gelatin, albumin) as the foundation for nanoparticle development. The paper meticulously examines their in vitro characteristics alongside in vivo efficacy, particularly focusing on their pivotal role in ameliorating diverse types of solid tumors within cancer therapy. The amalgamation of material science ingenuity and biological insight has led to the formulation of these nanoparticles, showcasing their potential to reshape the landscape of cancer treatment.

Advancements in hydrogel-based drug delivery systems for the treatment of inflammatory bowel disease: a review

Inflammatory bowel disease (IBD) is a chronic disorder that affects millions of individuals worldwide. However, current drug therapies for IBD are plagued by significant side effects, low efficacy, and poor patient compliance. Consequently, there is an urgent need for novel therapeutic approaches to alleviate IBD. Hydrogels, three-dimensional networks of hydrophilic polymers with the ability to swell and retain water, have emerged as promising materials for drug delivery in the treatment of IBD due to their biocompatibility, tunability, and responsiveness to various stimuli. In this review, we summarize recent advancements in hydrogel-based drug delivery systems for the treatment of IBD. We first identify three pathophysiological alterations that need to be addressed in the current treatment of IBD: damage to the intestinal mucosal barrier, dysbiosis of intestinal flora, and activation of inflammatory signaling pathways leading to disequilibrium within the intestines. Subsequently, we discuss in depth the processes required to prepare hydrogel drug delivery systems, from the selection of hydrogel materials, types of drugs to be loaded, methods of drug loading and drug release mechanisms to key points in the preparation of hydrogel drug delivery systems. Additionally, we highlight the progress and impact of the hydrogel-based drug delivery system in IBD treatment through regulation of physical barrier immune responses, promotion of mucosal repair, and improvement of gut microbiota. In conclusion, we analyze the challenges of hydrogel-based drug delivery systems in clinical applications for IBD treatment, and propose potential solutions from our perspective.

Polysaccharide-based hydrogels for medical devices, implants and tissue engineering: A review

Hydrogels are highly biocompatible biomaterials composed of crosslinked three-dimensional networks of hydrophilic polymers. Owing to their natural origin, polysaccharide-based hydrogels (PBHs) possess low toxicity, high biocompatibility and demonstrate in vivo biodegradability, making them great candidates for use in various biomedical devices, implants, and tissue engineering. In addition, many polysaccharides also show additional biological activities such as antimicrobial, anticoagulant, antioxidant, immunomodulatory, hemostatic, and anti-inflammatory, which can provide additional therapeutic benefits. The porous nature of PBHs allows for the immobilization of antibodies, aptamers, enzymes and other molecules on their surface, or within their matrix, potentiating their use in biosensor devices. Specific polysaccharides can be used to produce transparent hydrogels, which have been used widely to fabricate ocular implants. The ability of PBHs to encapsulate drugs and other actives has been utilized for making neural implants and coatings for cardiovascular devices (stents, pacemakers and venous catheters) and urinary catheters. Their high water-absorption capacity has been exploited to make superabsorbent diapers and sanitary napkins. The barrier property and mechanical strength of PBHs has been used to develop gels and films as anti-adhesive formulations for the prevention of post-operative adhesion. Finally, by virtue of their ability to mimic various body tissues, they have been explored as scaffolds and bio-inks for tissue engineering of a wide variety of organs. These applications have been described in detail, in this review.

Exploring the Potential of Nanogels: From Drug Carriers to Radiopharmaceutical Agents

Nanogels open up access to a wide range of applications and offer among others hopeful approaches for use in the field of biomedicine. This review provides a brief overview of current developments of nanogels in general, particularly in the fields of drug delivery, therapeutic applications, tissue engineering, and sensor systems. Specifically, cyclodextrin (CD)-based nanogels are important because they have exceptional complexation properties and are highly biocompatible. Nanogels as a whole and CD-based nanogels in particular can be customized in a wide range of sizes and equipped with a desired surface charge as well as containing additional molecules inside and outside, such as dyes, solubility-mediating groups or even biological vector molecules for pharmaceutical targeting. Currently, biological investigations are mainly carried out in vitro, but more and more in vivo applications are gaining importance. Modern molecular imaging methods are increasingly being used for the latter. Due to an extremely high sensitivity and the possibility of obtaining quantitative data on pharmacokinetic and pharmacodynamic properties, nuclear methods such as single photon emission computed tomography (SPECT) and positron emission tomography (PET) using radiolabeled compounds are particularly suitable here. The use of radiolabeled nanogels for imaging, but also for therapy, is being discussed.

Translational Challenges and Prospective Solutions in the Implementation of Biomimetic Delivery Systems

Biomimetic delivery systems (BDSs), inspired by the intricate designs of biological systems, have emerged as a groundbreaking paradigm in nanomedicine, offering unparalleled advantages in therapeutic delivery. These systems, encompassing platforms such as liposomes, protein-based nanoparticles, extracellular vesicles, and polysaccharides, are lauded for their targeted delivery, minimized side effects, and enhanced therapeutic outcomes. However, the translation of BDSs from research settings to clinical applications is fraught with challenges, including reproducibility concerns, physiological stability, and rigorous efficacy and safety evaluations. Furthermore, the innovative nature of BDSs demands the reevaluation and evolution of existing regulatory and ethical frameworks. This review provides an overview of BDSs and delves into the multifaceted translational challenges and present emerging solutions, underscored by real-world case studies. Emphasizing the potential of BDSs to redefine healthcare, we advocate for sustained interdisciplinary collaboration and research. As our understanding of biological systems deepens, the future of BDSs in clinical translation appears promising, with a focus on personalized medicine and refined patient-specific delivery systems.

Nanotechnology-Based Drug Delivery Systems to Control Bacterial-Biofilm-Associated Lung Infections

Airway mucus dysfunction and impaired immunological defenses are hallmarks of several lung diseases, including asthma, cystic fibrosis, and chronic obstructive pulmonary diseases, and are mostly causative factors in bacterial-biofilm-associated respiratory tract infections. Bacteria residing within the biofilm architecture pose a complex challenge in clinical settings due to their increased tolerance to currently available antibiotics and host immune responses, resulting in chronic infections with high recalcitrance and high rates of morbidity and mortality. To address these unmet clinical needs, potential anti-biofilm therapeutic strategies are being developed to effectively control bacterial biofilm. This review focuses on recent advances in the development and application of nanoparticulate drug delivery systems for the treatment of biofilm-associated respiratory tract infections, especially addressing the respiratory barriers of concern for biofilm accessibility and the various types of nanoparticles used to combat biofilms. Understanding the obstacles facing pulmonary drug delivery to bacterial biofilms and nanoparticle-based approaches to combatting biofilm may encourage researchers to explore promising treatment modalities for bacterial-biofilm-associated chronic lung infections.

Natural Polymer-Based Hydrogels: From Polymer to Biomedical Applications

Hydrogels prepared from natural polymer have attracted extensive attention in biomedical fields such as drug delivery, wound healing, and regenerative medicine due to their good biocompatibility, degradability, and flexibility. This review outlines the commonly used natural polymer in hydrogel preparation, including cellulose, chitosan, collagen/gelatin, alginate, hyaluronic acid, starch, guar gum, agarose, and dextran. The polymeric structure and process/synthesis of natural polymers are illustrated, and natural polymer-based hydrogels including the hydrogel formation and properties are elaborated. Subsequently, the biomedical applications of hydrogels based on natural polymer in drug delivery, tissue regeneration, wound healing, and other biomedical fields are summarized. Finally, the future perspectives of natural polymers and hydrogels based on them are discussed. For natural polymers, novel technologies such as enzymatic and biological methods have been developed to improve their structural properties, and the development of new natural-based polymers or natural polymer derivatives with high performance is still very important and challenging. For natural polymer-based hydrogels, novel hydrogel materials, like double-network hydrogel, multifunctional composite hydrogels, and hydrogel microrobots have been designed to meet the advanced requirements in biomedical applications, and new strategies such as dual-cross-linking, microfluidic chip, micropatterning, and 3D/4D bioprinting have been explored to fabricate advanced hydrogel materials with designed properties for biomedical applications. Overall, natural polymeric hydrogels have attracted increasing interest in biomedical applications, and the development of novel natural polymer-based materials and new strategies/methods for hydrogel fabrication are highly desirable and still challenging.

Polysaccharide‑platinum complexes for cancer theranostics

Platinum anticancer drugs have been explored and developed in recent years to reduce systematic toxicities and resist drug resistance. Polysaccharides derived from nature have abundant structures as well as pharmacological activities. The review provides insights on the design, synthesis, characterization and associating therapeutic application of platinum complexes with polysaccharides that are classified by electronic charge. The complexes give birth to multifunctional properties with enhanced drug accumulation, improved tumor selectivity and achieved synergistic antitumor effect in cancer therapy. Several techniques developing polysaccharides-based carriers newly are also discussed. Moreover, the lasted immunoregulatory activities of innate immune reactions triggered by polysaccharides are summarized. Finally, we discuss the current shortcomings and outline potential strategies for improving platinum-based personalized cancer treatment. Using platinum-polysaccharides complexes for improving the immunotherapy efficiency represents a promising framework in future.

Preparation of injectable hydrophilic dextran/AgNPs nanocomposite product: White light active biomolecules as an antitumor agent

Incidence of various cancers including melanoma continues to rise worldwide. While treatment options have expanded in the recent years, the benefit of these treatments suffer from short period of duration for many patients. Hence, new treatment options are highly desired. Here, we propose a method combining a Dextran/reactive-copolymer/AgNPs nanocomposite and a harmless visible light approach to obtain a plasma substitute carbohydrate-based nanoproduct (D@AgNP) that shows strong antitumor activity. Light-driven polysaccharide-based nanocomposite provided essential conditions for extra small (8-12nm) AgNPs capping with subsequent specific self-assembly into spherical-like cloud nanostructures. Obtained biocompatible D@AgNP are stable over six months at room temperature and demonstrated absorbance peak at 406 nm. New formulated nanoproduct revealed efficient anticancer properties against A375 with IC50 0.0035 mg/mL following 24-h incubation; complete cell death is achieved at 0.001 mg/mL and 0.0005 mg/mL by 24- and 48-h time points, respectively. SEM examination shows that D@AgNP altered the shape of the cell structure and damaged the cell membrane. TEM finding shows that D@AgNP are mostly localized at vesicles such as the endosomes, lysosomes and mitochondria. It is anticipated that the introduced new method serves as the cornerstone for improving the generation of biocompatible hydrophilic carbohydrate-based anticancer drugs.

Biological Macromolecule-Based Scaffolds for Urethra Reconstruction

Urethral reconstruction strategies are limited with many associated drawbacks. In this context, the main challenge is the unavailability of a suitable tissue that can endure urine exposure. However, most of the used tissues in clinical practices are non-specialized grafts that finally fail to prevent urine leakage. Tissue engineering has offered novel solutions to address this dilemma. In this technology, scaffolding biomaterials characteristics are of prime importance. Biological macromolecules are naturally derived polymers that have been extensively studied for various tissue engineering applications. This review discusses the recent advances, applications, and challenges of biological macromolecule-based scaffolds in urethral reconstruction.

CLEC4A and CLEC12B C-type lectin receptors mediate interactions with Pneumocystis cell wall components

Introduction. C-type lectin receptors (CLRs) are prominently expressed on myeloid cells where they perform multiple functions including serving as pattern recognition receptors (PRRs) to drive innate as well as adaptive immunity to pathogens. Depending on the presence of a tyrosine-based signalling motif, CLR-microbial pathogen engagement may result in either anti- or pro-inflammatory signalling.Impact statement. In this manuscript, we report our laboratory study of two novel CLRs that recognize Pneumocystis murina cell wall homogenates (CWH) and a purified Pneumocystis carinii cell wall fraction (CWF).Aim. To study the potential of newly generated hFc-CLR fusions on binding to Pneumocystis murina CWHs and P. carinii CWFs and subsequent downstream inflammatory signalling analysis.Methods. Newly generated hFc-CLR fusion CLEC4A and CLEC12B were screened against P. murina CWHs and P. carinii CWFs preparations via modified ELISA. Immunofluorescence assay (IFA) was utilized to visualize hFc-CLR fusion binding against intact fixed fungal life forms to verify results. Quantitative PCR (q-PCR) analysis of lung mRNA from the mouse immunosuppressed Pneumocystis pneumonia (PCP) model versus uninfected mice was employed to detect possible changes in the respective Clec4a and Clec12b transcripts. Lastly, siRNA technology of both CLRs was conducted to determine effects on downstream inflammatory events in mouse macrophages stimulated in the presence of P. carinii CWFs.Results. We determined that both CLEC4A and CLEC12B hFc-CLRs displayed significant binding with P. murina CWHs and P. carinii CWFs. Binding events showed significant binding to both curdlan and laminarin, both polysaccharides containing β-(1,3) glucans as well as N-acetylglucosamine (GlcNAc) residues and modest yet non-significant binding to the negative control carbohydrate dextran. IFA with both CLR hFc-fusions against whole P. murina life forms corroborated these findings. Lastly, we surveyed the mRNA expression profiles of both CLRs tested above in the mouse immunosuppressed Pneumocystis pneumonia (PCP) model and determined that both CLRs were significantly up regulated during infection. Lastly, siRNA of both CLRs in the mouse RAW macrophage cell line was conducted and results demonstrated that silencing of Clec4a resulted in no significant changes in TNF-alpha generation in P. carinii CWF stimulated macrophages. On the contrary, silencing of Clec12b CLR resulted in significant decreases in TNF-alpha in RAW cells stimulated with the same CWF.Conclusion. The data presented here provide new members of the CLRs family recognizing Pneumocystis. Future studies using CLEC4A and/or CLEC12B deficient mice in the PCP mouse model should provide further insights into the host immunological response to Pneumocystis.

Tofacitinib combined with melanocyte protector α-MSH to treat vitiligo through dextran based hydrogel microneedles

Vitiligo can cause serious damage to the appearance of patients and affect physical and mental health, but there is currently no simple and effective treatment. According to the theory of autoimmune disorder, the separable hydrogel microneedles delivering alpha-melanocyte-stimulating hormone (α-MSH) and tofacitinib were designed to treat vitiligo. This hydrogel microneedles were formed by dextran methacrylate (DexMA) and cyclodextrin-adamantane based host-guest supramolecules (HGSM) through CC double bond polymerization and host-guest assembly. The microneedle tips formed by the double cross-linked hydrogel can pierce the stratum corneum and deliver melanocyte protector α-MSH and JAK inhibitor tofacitinib directly to the epidermis and dermis. Under the treatment of α-MSH/tofacitinib microneedles, massive deposition of melanin in epidermis and hair follicles significantly accelerated skin and hair pigmentation.

Oral spatial-to-point cascade targeting "sugar-coated bullets" for precise and safe chemotherapy by intervention Warburg effect

Glycolysis plays a vital role in the development and progression of tumors. Inhibiting glycolysis via smart and safe methods serves as a promising target for cancer therapy. Here, an oral "sugar-coated bullet" aiming at intervening Warburg effect is designed by coating colloidal mesoporous silica nanoparticles (CMS) encapsulating glycolysis inhibitor shikonin (SHK) with dextran, namely DCMS/SHK. The solubility and drug-loading capacity of SHK were enhanced by the special structure of CMS. Besides, the tempting bullets possess the spatial-to-point cascade targeting ability in delivering SHK from the colonic lumen to colon cancer cells and finally to PKM2. After DCMS/SHK reaches the colon, the dextran is hydrolyzed by dextranase especially existing in the colon site to glucose and the carriers become glucose-coated nanoparticles. The glucose-cloak nanoparticles would be largely endocytosed by tumor cells and complete the efficient delivery of SHK. The encapsulated SHK can prevent the glycolysis of cancer cells and thus inhibit tumor growth effectively. This work presents an ingenious cascade colon-targeting strategy to treat colon cancer by destroying cell energy metabolism.

Advancements in antimicrobial nanoscale materials and self-assembling systems

Antimicrobial resistance is directly responsible for more deaths per year than either HIV/AIDS or malaria and is predicted to incur a cumulative societal financial burden of at least $100 trillion between 2014 and 2050. Already heralded as one of the greatest threats to human health, the onset of the coronavirus pandemic has accelerated the prevalence of antimicrobial resistant bacterial infections due to factors including increased global antibiotic/antimicrobial use. Thus an urgent need for novel therapeutics to combat what some have termed the 'silent pandemic' is evident. This review acts as a repository of research and an overview of the novel therapeutic strategies being developed to overcome antimicrobial resistance, with a focus on self-assembling systems and nanoscale materials. The fundamental mechanisms of action, as well as the key advantages and disadvantages of each system are discussed, and attention is drawn to key examples within each field. As a result, this review provides a guide to the further design and development of antimicrobial systems, and outlines the interdisciplinary techniques required to translate this fundamental research towards the clinic.

Recent Advances in the Development of Tetrazine Ligation Tools for Pretargeted Nuclear Imaging

Tetrazine ligation has gained interest as a bio-orthogonal chemistry tool within the last decade. In nuclear medicine, tetrazine ligation is currently being explored for pretargeted approaches, which have the potential to revolutionize state-of-the-art theranostic strategies. Pretargeting has been shown to increase target-to-background ratios for radiopharmaceuticals based on nanomedicines, especially within early timeframes. This allows the use of radionuclides with short half-lives which are more suited for clinical applications. Pretargeting bears the potential to increase the therapeutic dose delivered to the target as well as reduce the respective dose to healthy tissue. Combined with the possibility to be applied for diagnostic imaging, pretargeting could be optimal for theranostic approaches. In this review, we highlight efforts that have been made to radiolabel tetrazines with an emphasis on imaging.

Development of pH-sensitive dextran-based methotrexate nanodrug for rheumatoid arthritis therapy through inhibition of JAK-STAT pathways

Rheumatoid arthritis (RA) is a chronic and symmetrical autoimmune disease that primarily characterized with articular synovial hyperplasia, joint swelling, cartilage and bone destruction. The in-depth understanding of the role of immune signaling pathway inhibitors provides inspiration for the construction of new and more effective strategy for RA therapy. In this study, by loading methotrexate (MTX) into an acetalated dextran biopolymer, AcDEX, we developed a pH-sensitive, MTX-loaded and molecularly targeted nanodrug MTX@pH-AcDEX NPs) to decrease the toxicity of MTX and simultaneously enhance its therapeutic effect. The resultant MTX@pH-AcDEX NPs showed the spherical morphology and notable pH-responsiveness with high drug loading of 88.32%. As demonstrated in vitro and in vivo, the reduced cytotoxicity of both RAW264.7 cells and LPS-activated RAW264.7 cells treated with MTX@pH-AcDEX NPs was found compared to free MTX. Upon intravenous administration into adjuvant-induced arthritis (AIA) rat model, the nanodrug had potent pharmacokinetic and pharmacodynamic profiles, which can accumulate in RA lesions and release MTX inhibitors for regulating the JAK-STAT pathways. As a result, the MTX@pH-AcDEX NPs achieved the cartilage and bone protective and a better anti-inflammatory effect with negligible systemic toxicity, suggesting the strong potential of safe and effective nanodrug for RA therapy as well as other autoimmune diseases.

Polymer-drug conjugates: Design principles, emerging synthetic strategies and clinical overview

Adagen, an enzyme replacement treatment for adenosine deaminase deficiency, was the first protein-polymer conjugate to be approved in early 1990s. Post this regulatory approval, numerous polymeric drugs and polymeric nanoparticles have entered the market as advanced or next-generation polymer-based therapeutics, while many others have currently been tested clinically. The polymer conjugation to therapeutic moiety offers several advantages, like enhanced solubilization of drug, controlled release, reduced immunogenicity, and prolonged circulation. The present review intends to highlight considerations in the design of therapeutically effective polymer-drug conjugates (PDCs), including the choice of linker chemistry. The potential synthetic strategies to formulate PDCs have been discussed along with recent advancements in the different types of PDCs, i.e., polymer-small molecular weight drug conjugates, polymer-protein conjugates, and stimuli-responsive PDCs, which are under clinical/preclinical investigation. Current impediments and regulatory hurdles hindering the clinical translation of PDC into effective therapeutic regimens for the amelioration of disease conditions have been addressed.

A Review of Recent Advances in Natural Polymer-Based Scaffolds for Musculoskeletal Tissue Engineering

The musculoskeletal (MS) system consists of bone, cartilage, tendon, ligament, and skeletal muscle, which forms the basic framework of the human body. This system plays a vital role in appropriate body functions, including movement, the protection of internal organs, support, hematopoiesis, and postural stability. Therefore, it is understandable that the damage or loss of MS tissues significantly reduces the quality of life and limits mobility. Tissue engineering and its applications in the healthcare industry have been rapidly growing over the past few decades. Tissue engineering has made significant contributions toward developing new therapeutic strategies for the treatment of MS defects and relevant disease. Among various biomaterials used for tissue engineering, natural polymers offer superior properties that promote optimal cell interaction and desired biological function. Natural polymers have similarity with the native ECM, including enzymatic degradation, bio-resorb and non-toxic degradation products, ability to conjugate with various agents, and high chemical versatility, biocompatibility, and bioactivity that promote optimal cell interaction and desired biological functions. This review summarizes recent advances in applying natural-based scaffolds for musculoskeletal tissue engineering.

Nanostructured particles assembled from natural building blocks for advanced therapies

Advanced treatments based on immune system manipulation, gene transcription and regulation, specific organ and cell targeting, and/or photon energy conversion have emerged as promising therapeutic strategies against a range of challenging diseases. Naturally derived macromolecules (e.g., proteins, lipids, polysaccharides, and polyphenols) have increasingly found use as fundamental building blocks for nanostructured particles as their advantageous properties, including biocompatibility, biodegradability, inherent bioactivity, and diverse chemical properties make them suitable for advanced therapeutic applications. This review provides a timely and comprehensive summary of the use of a broad range of natural building blocks in the rapidly developing field of advanced therapeutics with insights specific to nanostructured particles. We focus on an up-to-date overview of the assembly of nanostructured particles using natural building blocks and summarize their key scientific and preclinical milestones for advanced therapies, including adoptive cell therapy, immunotherapy, gene therapy, active targeted drug delivery, photoacoustic therapy and imaging, photothermal therapy, and combinational therapy. A cross-comparison of the advantages and disadvantages of different natural building blocks are highlighted to elucidate the key design principles for such bio-derived nanoparticles toward improving their performance and adoption. Current challenges and future research directions are also discussed, which will accelerate our understanding of designing, engineering, and applying nanostructured particles for advanced therapies.

Dextran, as a biological macromolecule for the development of bioactive wound dressing materials: A review of recent progress and future perspectives

Skin is the largest organ in the body which plays different roles in maintaining hemostasis. Although this tissue has a high healing potential, severe skin wounds cannot heal without external interventions. Among various treatment strategies, tissue-engineered wound dressings have gained significant attention. In this regard, tremendous progress has been made in the field of tissue engineering to develop constructs with higher healing activities. Material selection and optimization are key factors in development of such dressings. Among different candidates, dextran-based wound dressings have been extensively studied. Dextran is a branched biological macromolecule which is composed of anhydroglucose monomers. Due to its excellent biocompatibility, biodegradability, non-toxicity, modifiable functional groups, and proven clinical safety, dextran has found application in wound healing research. In the current review, applications, challenges, and future perspectives of dextran-based wound dressings will be discussed.

Role of Polysaccharides Mimetic Components in Targeted Cancer Treatment

Organic or inorganic compounds are synthesized or formulated in a manner that they completely show their therapeutic actions like as a natural polysaccharide in the body. Polysaccharides, the major type of natural polymers, are efficiently biologically active, non-toxic, hydrophilic, and biodegradable and show various properties. In this manuscript, the main focus is on delivering anticancer drugs with the help of mimetic components of polysaccharides. All data collected for this manuscript was from PubMed, Elsevier, Taylor, and Francis Bentham science journals. Most chemotherapeutics are therapeutically toxin to the human body, have a narrow therapeutic index, sluggish pharmaceutical delivery mechanisms, and are poorly soluble in water. The use of mimetic components of polysaccharides leads to the enhancement of the solubility of drugs in the biological environment. The manuscript summarizes the use of mimetic components of polysaccharides along with anticancer agents which are capable to inhibit the growth of cancerous cells in the body which shows lesser adverse effects in the biological system compared to other therapies.

Regioselective synthesis of polysaccharide-amino acid ester conjugates

Site-specific conjugation of polysaccharides with proteins is very challenging. Creating the ability to control chemo- and regioselective reaction between polysaccharides and amino acid derivatives can not only create potentially useful and bioactive natural polymer constructs, but should also provide useful guidance for the principles of polysaccharide-protein conjugate synthesis. In this work, we exploited regioselective bromination of the non-reducing end primary dextran hydroxyl using N-bromosuccinimide (NBS) and triphenylphosphine (Ph₃P) in the dimethylacetamide (DMAc) and lithium bromide solvent system, thereby enabling a regio- and chemoselective synthetic strategic approach to a variety of polysaccharide-amino acid ester adducts. We demonstrated selective condensation of the α-amino groups of esters of the amino acids tyrosine and proline, displacing the single, terminal C6 bromides of 6-BrDextran, as well as the 6-Br moieties of 6-BrCA320S, with high conversion (71-96%). Histidine ester side group amines were found to react with 6-BrCA320S, while those of tryptophan ester did not. These results provide useful access to polysaccharide-amino acid ester adducts of various architectures, and guide us in designing new pathways to polysaccharide-protein copolymers.

Polysaccharide/mesoporous silica nanoparticle-based drug delivery systems: A review

Mesoporous silica nanoparticles (MSNs) have been well-researched in the design and fabrication of advanced drug delivery systems (DDSs) due to their advantages such as good biocompatibility, large specific surface area and pore volume for drug loading, easily surface modification, adjusted size and good thermal/chemical stability. For MSN-based DDSs, gate materials are also necessary. And natural polysaccharides, one kind of the most abundant natural resource, have been widely applied as the "gatekeepers" in MSN-based DDSs. Polysaccharides are cheap and rich in sources with good biocompatibility, and some of them have important biological functions. In this review article, polysaccharides including chitosan, hyaluronic acid, sodium alginate and dextran, et al. are briefly introduced. And the preparation processes and properties such as controlled drug release, cancer targeting and disease diagnosis of functional polysaccharide/MSN-based DDSs are discussed.

Synthesis, characterization, and cytotoxicity evaluation of dextran-myristoyl-ECGKRK peptide conjugate

CGKRK is a well-known tumor homing peptide with significant specificity for many types of cancer tissues. Herein, we describe the synthesis of a novel drug delivery system based on dextran decorated with myristoyl-ECGKRK peptide. The myristoylated peptide was synthesized and conjugated to dextran via an ester bond followed by purification. FT-IR and NMR confirmed the success of the conjugation reaction, while the surface morphology examination revealed that the conjugate has a characteristic porous network-like structure. Dynamic-light scattering measurements indicated the ability of the conjugate to self-assemble into nanoparticles with an average size of 248 ± 6.33 nm, and zeta potential of 10.7 mV. The cytotoxicity profiles for the peptide, dextran (Dex0), and dextran-peptide conjugate (Dex1) were evaluated against triple-negative breast cancer cells (MDA-MB-231), breast cancer cells (MCF-7), and human embryonic normal kidney cells (HEK-293). The results revealed that myristoyl-ECGKRK was noncytotoxic on the two different breast cancer cell lines up to 50 μM, but the cell viability was minimally reduced to 85% at 50 μm in HEK-293 cells. Similarly, Dex0 showed a neglected cytotoxicity profile at all tested concentrations. The Dex1 was not toxic to the cells up to a concentration of 8.3 mg/mL.

Synthesis, cytotoxicity assay, pharmacokinetics, biodistribution and modeling study of cabazitaxel-dextran nanoconjugates: targeted vs non targeted delivery

Cabazitaxel (CTX) is an anti-neoplastic agent of second-generation taxane derivatives, characterized by very low water solubility. The currently marketed formulation of CTX contains high concentrations of surfactant and ethanol, which causes severe hypersensitivity reactions in patients. To deal with aforementioned side effects, our previous study attempted to develop the prodrugs of CTX with dextran. Here our approach differs through synthesizing folate containing prodrug and also investigating cytotoxicity and pharmacokinetics parameters obtained with dextran and dextran-folate nanoconjugates versus free CTX. MCF-7 with medium folate receptor expression and MDA-MB-231 as high folate receptor expression cell lines were selected for cytotoxicity assay. Pharmacokinetics properties were studied by injecting prodrugs and CTX to Wistar rats, analyzing serum and selected tissue samples and the obtained results were sibjected to data modeling study. The size of synthesized prodrugs was mostly less than 90 nm. Folate conjugates provided higher toxicity in comparison with dextran conjugates on both cell lines. In vivo non-compartmental pharmacokinetics analysis revealed enhanced area under the curve (about 3-5 fold for different samples) and longer half-life (approximately 1.3-1.8 fold higher) which led to increased serum residence time of prodrugs in comparison to free CTX. Tissue accumulation data showed that liver was the major organ with high accumulation of CTX. The accumulation of folate conjugates was remarkably higher than dextran samples (p < 0.05 in samples of 2, 10 and 24 h). Data modeling by Principal Component Analysis (PCA) and Hierarchical Cluster models showed a significant difference between pharmacokinetics properties of CTX and prodrugs. In summary, prodrugs seem to be proper and promising CTX delivery systems as substitution for the current market formulation.

Enhancing cisplatin anticancer effectivity and migrastatic potential by modulation of molecular weight of oxidized dextran carrier

The molecular weight (M_w) of dextran derivatives, such as regioselectively oxidized dicarboxydextran (DXA), is greatly influencing their faith in an organism, which could be possibly used to improve anticancer drug delivery. Here we present a modified method of sulfonation-induced chain scission allowing direct and accurate control over the M_w of DXA without increasing its polydispersity. Prepared DXA derivatives (M_w = 10-185 kDa) have been conjugated to cisplatin and the M_w of the carrier found to have a significant impact on cisplatin release rates, in vitro cytotoxicity, and migrastatic potential. Conjugates with the high-M_w DXA showed particularly increased anticancer efficacy. The best conjugate was four times more effective against malignant prostatic cell lines than free cisplatin and significantly inhibited the ovarian cancer cell migration. This was traced to the characteristics of spontaneously formed cisplatin-crosslinked DXA nanogels influenced by M_w of DXA and amount of loaded cisplatin.

Insulin- and cholic acid-loaded zein/casein-dextran nanoparticles enhance the oral absorption and hypoglycemic effect of insulin

Diabetes mellitus is the most common metabolic disease in the world. Herein, insulin- and cholic acid-loaded zein nanoparticles with dextran surfaces were fabricated to enhance the oral absorptions of insulin in the intestine and in the liver which is the primary action organ of endogenous insulin. In the nanoparticles, zein acted as cement to embed insulin, cholic acid and casein by hydrophobic interactions. The hydrophilic dextran conjugated to casein by the Maillard reaction was located on the nanoparticle surface. The nanoparticles had an insulin loading efficiency of 74.6%, a cholic acid loading efficiency of 55.1% and a hydrodynamic diameter of 267 nm. The dextran significantly increased the disperse stability of the nanoparticles, protected the loaded insulin from hydrolysis in digestive juices, and increased the trans-mucus permeability of the insulin. The embedded cholic acid molecules were consecutively exposed to the surface when the nanoparticles were gradually eroded by proteases. The exposed cholic acid promoted the absorptions of the nanoparticles in the ileum and liver via bile acid transporters. The effect of pretreated lymphatic transport inhibitor cycloheximide revealed that about half of the nanoparticles were transported via the intestinal lymphatic transport pathway and the other half of the nanoparticles were transported via portal blood absorption. The oral pharmacological bioavailability of the nanoparticles in type I diabetic mice was 12.5-20.5%. This study demonstrates that nanoparticles are a promising oral delivery system for insulin.

Recent advances in the production of biomedical systems based on polyhydroxyalkanoates and exopolysaccharides

In recent years, growing attention has been devoted to naturally occurring biological macromolecules and their ensuing application in agriculture, cosmetics, food and pharmaceutical industries. They inherently have antigenicity, low immunogenicity, excellent biocompatibility and cytocompatibility, which are ideal properties for the design of biomedical devices, especially for the controlled delivery of active ingredients in the most diverse contexts. Furthermore, these properties can be modulated by chemical modification via the incorporation of other (macro)molecules in a random or controlled way, aiming at improving their functionality for each specific application. Among the wide variety of natural polymers, microbial polyhydroxyalkanoates (PHAs) and exopolysaccharides (EPS) are often considered for the development of original biomaterials due to their unique physicochemical and biological features. Here, we aim to fullfil a gap on the present associated literature, bringing an up-to-date overview of ongoing research strategies that make use of PHAs (poly (3-hydroxybutyrate), poly (3-hydroxybutyrate-co-3-hydroxyvalerate), poly (3-hydroxyoctanoate), poly(3-hydroxypropionate), poly (3-hydroxyhexanoate-co-3-hydroxyoctanoate), and poly (3-hydroxybutyrate-co-3-hydroxyhexanoate)) and EPS (bacterial cellulose, alginates, curdlan, pullulan, xanthan gum, dextran, hyaluronan, and schizophyllan) as sources of interesting and versatile biomaterials. For the first time, a monograph addressing the properties, pros and cons, status, challenges, and recent progresses regarding the application of these two important classes of biopolymers in biomedicine is presented.

Chitosan-based blends for biomedical applications

Polysaccharides are the most abundant naturally available carbohydrate polymers; composed of monosaccharide units covalently connected together. Chitosan is the most widely used polysaccharides because of its exceptional biocompatibility, mucoadhesion, and chemical versatility. However, it suffers from a few drawbacks, e.g. poor mechanical properties and antibacterial activity for biomedical applications. Blending chitosan with natural or synthetic polymers may not merely improve its physicochemical and mechanical properties, but may also improve its bioactivity-induced properties. This review paper summarizes progress in chitosan blends with biodegradable polymers and polysaccharides and their biomedical applications. Blends of chitosan with alginate, starch, cellulose, pectin and dextran and their applications were particularly addressed. The critical and challenging aspects as well as the future ahead of the use of chitosan-based blends were eventually enlightened.

Tuning the strength and swelling of an injectable polysaccharide hydrogel and the subsequent release of a broad spectrum bacteriocin, nisin A

Bacteriocins, which are antimicrobial peptides, are a potential alternative to current ineffective antimicrobial therapies. They can inhibit the growth of clinically relevant pathogens but their proteinaceous nature renders them susceptible to degradation and deactivation in vivo. We have designed injectable polysaccharide hydrogels for the controlled release of an incorporated bacteriocin, nisin. Nisin was encapsulated into these hydrogels which were composed of varying percentages of oxidised dextran, alginate functionalised with hydrazine groups and glycol chitosan. The nisin gels exhibited antimicrobial activity against Staphylococcus aureus up to 10 days. The incorporation of a deacetylated chitosan and the reduction of alginate-hydrazine could be used to tune the gel's swelling behaviour, strength and the subsequent release profile of nisin. Glycol chitosan also shows synergistic inhibition of S. aureus with nisin.

Synthesis and self-assembly of curcumin-modified amphiphilic polymeric micelles with antibacterial activity

BACKGROUND

The ubiquitous nature of bacterial biofilms combined with the enhanced resistance towards antimicrobials has led to the development of an increasing number of strategies for biofilm eradication. Such strategies must take into account the existence of extracellular polymeric substances, which obstruct the diffusion of antibiofilm agents and assists in the maintenance of a well-defended microbial community. Within this context, nanoparticles have been studied for their drug delivery efficacy and easily customised surface. Nevertheless, there usually is a requirement for nanocarriers to be used in association with an antimicrobial agent; the intrinsically antimicrobial nanoparticles are most often made of metals or metal oxides, which is not ideal from ecological and biomedical perspectives. Based on this, the use of polymeric micelles as nanocarriers is appealing as they can be easily prepared using biodegradable organic materials.

RESULTS

In the present work, micelles comprised of poly(lactic-co-glycolic acid) and dextran are prepared and then functionalised with curcumin. The effect of the functionalisation in the micelle's physical properties was elucidated, and the antibacterial and antibiofilm activities were assessed for the prepared polymeric nanoparticles against Pseudomonas spp. cells and biofilms. It was found that the nanoparticles have good penetration into the biofilms, which resulted in enhanced antibacterial activity of the conjugated micelles when compared to free curcumin. Furthermore, the curcumin-functionalised micelles were efficient at disrupting mature biofilms and demonstrated antibacterial activity towards biofilm-embedded cells.

CONCLUSION

Curcumin-functionalised poly(lactic-co-glycolic acid)-dextran micelles are novel nanostructures with an intrinsic antibacterial activity tested against two Pseudomonas spp. strains that have the potential to be further exploited to deliver a secondary bioactive molecule within its core.

Oxidized polysaccharides for anticancer-drug delivery: What is the role of structure?

Study provides an in-depth analysis of the structure-function relationship of polysaccharide anticancer drug carriers and points out benefits and potential drawbacks of differences in polysaccharide glycosidic bonding, branching and drug binding mode of the carriers. Cellulose, dextrin, dextran and hyaluronic acid have been regioselectively oxidized to respective dicarboxylated derivatives, allowing them to directly conjugate cisplatin, while preserving their major structural features intact. The structure of source polysaccharide has crucial impact on conjugation effectiveness, carrier capacity, drug release rates, in vitro cytotoxicity and cellular uptake. For example, while branched structure of dextrin-based carrier partially counter the undesirable initial burst release, it also attenuates the cellular uptake and the cytotoxicity of carried drug. Linear polysaccharides containing β-(1→4) glycosidic bonds and oxidized at C2 and C3 (cellulose and hyaluronate) have the best overall combination of structural features for improved drug delivery applications including potentiation of the cisplatin efficacy towards malignances.

Polymeric micelles in cancer therapy: State of the art

In recent years, polymeric micelles have been extensively utilized in pre-clinical studies for delivering poorly soluble chemotherapeutic agents in cancer. Polymeric micelles are formed via self-assembly of amphiphilic polymers in facile manners. The wide availability of hydrophobic and, to some extent, hydrophilic polymeric blocks allow researchers to explore various polymeric combinations for optimum loading, stability, systemic circulation, and delivery to the target cancer tissues. Moreover, polymeric micelles could easily be tailor-made by increasing and decreasing the number of monomers in each polymeric chain. Some of the widely accepted hydrophobic polymers are poly(lactide) (PLA), poly(caprolactone) (PCL), poly(lactide-co-glycolide) (PLGA), polyesters, poly(amino acids), lipids. The hydrophilic polymers used to wrap the hydrophobic core are poly(ethylene glycol), poly(oxazolines), chitosan, dextran, and hyaluronic acids. Drugs could be conjugated to polymers at the distal ends to prepare pharmacologically active polymeric systems that impart enhanced solubility and stability of the conjugates and provide an opportunity for combination drug delivery. Their nano-size enables them to accumulate to the tumor microenvironment via the Enhanced Permeability and Retention (EPR) effect. Moreover, the stimuli-sensitive breakdown provides the micelles an effective means to deliver the therapeutic cargo effectively. The tumor micro-environmental stimuli are pH, hypoxia, and upregulated enzymes. Externally applied stimuli to destroy micellar disassembly to release the payload include light, ultrasound, and temperature. This article delineates the current trend in developing polymeric micelles combining various block polymeric scaffolds. The development of stimuli-sensitive micelles to achieve enhanced therapeutic activity are also discussed.

Lactic acid bacteria-derived α-glucans: From enzymatic synthesis to miscellaneous applications

Lactic acid bacteria (LAB) are capable of producing a variety of exopolysaccharide α-glucans, such as dextran, mutan, reuteran, and alternan. Their structural diversity allows LAB-derived α-glucans to hold vast commercial value and application potential in the food, cosmetic, medical, and biotechnology fields, garnering much attention in recent years. Glycoside Hydrolase 70 family (GH70) enzymes are efficient tools for the biosynthesis of α-glucans with various sizes, linkage compositions, and degrees of branching, using renewable and low-cost sucrose and starch as substrates. To date, plenty of various LAB-derived GH70 glucansucrases (especially dextransucrase) have been biochemically characterized to synthesize α-glucans from sucrose with a variety of structural organizations. This review mainly aimed at the biotechnological synthesis of α-glucans using GH70 family enzymes and their diverse (potential) applications. The purification, structural analysis and physicochemical properties of α-glucan polysaccharides were reviewed in detail. Synchronously, some new insights and future perspectives of LAB-derived α-glucans enzymatic synthesis and applications were also discussed. To expand the range of applications, the physicochemical properties and bioactivities of LAB-derived α-glucans, other than dextran, should be further explored. Additionally, screening novel GH70 subfamily starch-acting enzymes is conducive to expanding the repertoire of α-glucans.

Engineering of smart nanoconstructs for delivery of glucagon-like peptide-1 analogs

Glucagon-like peptide-1 (GLP-1) receptor agonists are being increasingly exploited in clinical practice for management of type 2 diabetes mellitus due to their ability to lower blood glucose levels and reduce off-target effects of current therapeutics. Nanomaterials had viewed myriad breakthroughs in protecting peptides against degradation and carrying therapeutics to targeted sites for maximizing their pharmacological activity and overcoming limitations associated with their application. This review highlights the latest advances in designing smart multifunctional nanoconstructs and engineering targeted and stimuli-responsive nanoassemblies for delivery of GLP-1 receptor agonists. Furthermore, advanced nanoconstructs of sophisticated supramolecular assembly yet efficient delivery of GLP-1/GLP-1 analogs, nanodevices that mediate intrinsic GLP-1 secretion per se, and nanomaterials with capabilities to load additional moieties for synergistic antidiabetic effects, are demonstrated.