Preparation and drug delivery of dextran-drug complex

Physicochemical and Biological Properties of Vancomycin-Containing Antibacterial Polysaccharide Gels for Biocomposite Bone Implant Impregnation

Polymeric drugs containing up to 60% by weight of the antibiotic vancomycin were synthesized based on dextran carriers activated with epichlorohydrin. Vancomycin was covalently bound, involving the primary amino group of the molecule through the hydroxypropyl radical to the C6 position of the anhydroglucose units of the dextran main chain. Covalent binding is necessary to prevent spontaneous release of the antibiotic from the gel, thereby reducing the risk of bacterial multiresistance. Antibacterial depot gels were obtained from those polymers, containing up to 17.5% by weight of polysaccharide with a cross-linking density of q = 3-5 nodes per macromolecule for the deposition of another type of drugs not covalently bound to the polymer gel. They were used to coat the surface of the internal pores of biocomposite bone implants based on bovine cancellous bone used in orthopedics. The chemical structure of the polymer was studied using 13C NMR spectroscopy and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. The stiffness of the gels was evaluated by the values of the accumulation modulus G' = 170-270 kPa and the loss modulus G″ = 3.7-4.2 kPa determined on a rheometer. Their values are close to those typical for materials used to replace soft tissue in plastic surgery. The minimum inhibitory concentration of the gels against Staphylococcus aureus P209 depends on the antibiotic content in the polymer. It equals 2.5 mg/L for vancomycin we used and 100 mg/L for a polymer containing 50% by weight of covalently bound antibiotic. The cytotoxic concentration measured with cell culture HEK 293T exceeds 1200 mg/L in 24 h exposure. The release dynamics of drugs not covalently bound to dextran from the depot gel were studied using fluorescein as a model. The release time is independent of the gel density and lasts up to 6 days for a 2 mm thick layer. Both the gel and the bone implants impregnated with it maintained consistently high antibacterial activity throughout the experiment, up to its completion after 168 h, with the local concentration of the released antibiotic at the site of bacterial attack exceeding the therapeutic level by 200 times.

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.

Multimodal characterization of the collagen hydrogel structure and properties in response to physiologically relevant pH fluctuations

pH fluctuations within the extracellular matrix (ECM) and its principal constituent collagen, particularly in solid tumors and chronic wounds, may influence its structure and function. Whereas previous research examined the impact of pH on collagen fibrillogenesis, this study focuses on determining how pH fluctuations affect collagen hydrogels that mimic the physiological ECM. Utilizing a type I collagen hydrogel, we examined the influence of pH fluctuations on its structure, properties, and function while keeping the collagen hydrated. We show that collagen's secondary structure remains unaltered during pathologically relevant microenvironmental pH changes. By employing cryo scanning electron microscopy and artificial intelligence-assisted image analysis, we show that at physiological pH, collagen hydrogel presents densely packed, aligned, and elongated fibrils, which upon a decrease to pH 6.5, are transformed into shorter, sparser, and disoriented fibrils. The collagen possesses a higher storage modulus yet a lower permeability at pH 7 and 7.8 compared with pH 6.5 and 7.4. Exposing acidified collagen to a basic buffer reinstates its native structure and viscoelastic properties. Our study offers an innovative approach to analyze and characterize perturbations in hydrated collagen-based systems with potential implications for better understanding and combating disease progression. STATEMENT OF SIGNIFICANCE: As the main component of the extracellular matrix, collagen undergoes conformational changes associated with pH changes during disease. We analyze the impact of pH on pre-formed collagen fibers mimicking healthy tissues subjected to disease, and do not focus on the more studied fibrillogenesis process. Using cryogenic SEM, which allowed imaging close to the native state, we show that even minor fluctuations in the pH affect the collagen thickness, length, fiber alignment, and rheological properties. Following exposure to acidic pH, the collagen had short fibers, lacked orientation, and had low mechanical strength. This acidic collagen restored its original properties after returning to a neutral pH. These findings can help determine how pH changes can be modulated to restore healthy collagen properties.

Novel method of measurement of in vitro drug uptake in OATP1B3 overexpressing cells in the presence of dextran

BACKGROUND

In predictions about hepatic clearance (CLH), a number of studies explored the role of albumin and transporters in drug uptake by liver cells, challenging the traditional free-drug theory. It was proposed that liver uptake can occur for transporter substrate compounds not only from the drug's unbound form but also directly from the drug-albumin complex, a phenomenon known as uptake facilitated by albumin. In contrast to albumin, dextran does not exhibit binding properties for compounds. However, as a result of its inherent capacity for stabilization, it is widely used to mimic conditions within cells.

METHODS

The uptake of eight known substrates of the organic anion-transporting polypeptide 1B3 (OATP1B3) was assessed using a human embryonic kidney cell line (HEK293), which stably overexpresses this transporter. An inert polymer, dextran, was used to simulate cellular conditions, and the results were compared with experiments involving human plasma and human serum albumin (HSA).

RESULTS

This study is the first to demonstrate that dextran increases compound uptake in cells with overexpression of the OATP1B3 transporter. Contrary to the common theory that highly protein-bound ligands interact with hepatocytes to increase drug uptake, the results indicate that dextran's interaction with test compounds does not significantly increase concentrations near the cell membrane surface.

CONCLUSIONS

We evaluated the effect of dextran on the uptake of known substrates using OATP1B3 overexpressed in the HEK293 cell line, and we suggest that its impact on drug concentrations in liver cells may differ from the traditional role of plasma proteins and albumin.

Recent Advances in Nanotechnology-Based Drug Delivery Systems for the Diagnosis and Treatment of Reproductive Disorders

Over the past decade, nanotechnology has seen extensive integration into biomedical applications, playing a crucial role in biodetection, drug delivery, and diagnostic imaging. This is especially important in reproductive health care, which has become an emerging and significant area of research. Global concerns have intensified around disorders such as infertility, endometriosis, ectopic pregnancy, erectile dysfunction, benign prostate hyperplasia, sexually transmitted infections, and reproductive cancers. Nanotechnology presents promising solutions to address these concerns by introducing innovative tools and techniques, facilitating early detection, targeted drug delivery, and improved imaging capabilities. Through the utilization of nanoscale materials and devices, researchers can craft treatments that are not only more precise but also more effective, significantly enhancing outcomes in reproductive healthcare. Looking forward, the future of nanotechnology in reproductive medicine holds immense potential for reshaping diagnostics, personalized therapies, and fertility preservation. The utilization of nanotechnology-driven drug delivery systems is anticipated to elevate treatment effectiveness, minimize side effects, and offer patients therapies that are not only more precise but also more efficient. This review aims to delve into the various types, properties, and preparation techniques of nanocarriers specifically designed for drug delivery in the context of reproductive disorders, shedding light on the current landscape and potential future directions in this dynamic field.

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.

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.

Advancements in dextran-based nanocarriers for treatment and imaging of breast cancer

Breast cancer is the most prevalent type of cancer worldwide,particularly among women, with substantial side effects after therapy. Despite the availability of numerous therapeutic approaches, particularly chemotherapy, the survival rates for breast cancer have declined over time. The therapies currently utilized for breast cancer treatment do not specifically target cancerous cells, resulting in significant adverse effects and potential harm to healthy cells alongside the cancer cells. As a result, nanoparticle-based drug delivery systems have emerged. Among various types of nanoparticles, natural polysaccharide-based nanoparticles have gained significant attention due to their ability to precisely control the drug release and achieve targeted drug delivery. Moreover, polysaccharides are biocompatible, biodegradable, easily modifiable, and renewable, which makes them a unique material for nanoformulation. In recent years, dextran and its derivatives have gained much interest in the field of breast cancer therapy. Dextran is a hydrophilic polysaccharide composed of a main chain formed by α-1,6 linked glucopyranoside residues and a side chain composed of residues linked in α-1,2/3/4 positions. Different dextran-antitumor medication conjugates enhancethe efficacy of anticancer agents. With this context, the present review provides brief insights into dextran and its modification. Further, it meticulously discusses the role of dextran-based nanoparticles in breast cancer therapy and imaging, followed by snippets on their toxicity. Lastly, it presents clinical trials and future perspectives of dextran-based nanoparticles in breast cancer treatment.

Oral Nanotherapeutics of Andrographolide/Carbon Monoxide Donor for Synergistically Anti-inflammatory and Pro-resolving Treatment of Ulcerative Colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease of unknown etiology affecting the colon and rectum. Current therapeutics are focused on suppressing inflammation but are ineffective. Combining anti-inflammatory therapeutic approaches with pro-resolution might be a superior strategy for UC treatment. Andrographolide (AG), an active compound from the plant Andrographis paniculata, presented anti-inflammatory effects in various inflammatory diseases. Gaseous mediators, such as carbon monoxide (CO), have a role in inflammatory resolution. Herein, we developed a dextran-functionalized PLGA nanocarrier for efficient delivery of AG and a carbon monoxide donor (CORM-2) for synergistically anti-inflammatory/pro-resolving treatment of UC (AG/CORM-2@NP-Dex) based on PLGA with good biocompatibility, slow drug release, efficient targeting, and biodegradability. The resulting nanocarrier had a nano-scaled diameter of ∼200 nm and a spherical shape. After being coated with dextran (Dex), the resulting AG/CORM-2@NP-Dex could be efficiently internalized by Colon-26 and Raw 264.7 cells in vitro and preferentially localized to the inflamed colon with chitosan/alginate hydrogel protection by gavage. AG/CORM-2@NP-Dex performed anti-inflammatory effects by eliminating the over-production of pro-inflammatory mediator, nitric oxide (NO), and down-regulating the expression of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6), while it showed pro-resolving function by accelerating M1 to M2 macrophage conversion and up-regulating resolution-related genes (IL-10, TGF-β, and HO-1). In the colitis model, oral administration of AG/CORM-2@NP-Dex in a chitosan/alginate hydrogel also showed synergistically anti-inflammatory/pro-resolving effects, therefore relieving UC effectively. Without appreciable systemic toxicity, this bifunctional nanocarrier represents a novel therapeutic approach for UC and is expected to achieve long-term inflammatory remission.

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.

Dextran-doxorubicin prodrug nanoparticles conjugated with CD147 monoclonal antibody for targeted drug delivery in hepatoma therapy

Antibody-drug conjugates (ADCs) are a class of tumor cell-targeting drugs that have developed rapidly in recent years. From the perspective of further improving ADC targeting and developing natural macromolecules as drug carriers, it is still challenging and necessary to try new targeted drug delivery modalities. In this study, we have developed an antibody-modified prodrug nanoparticle based on biomacromolecule dextran (DEX) to delivery antitumour drug doxorubicin (DOX). Firstly, oxidized dextran (ODEX) and DOX were bonded to yield ODEX-DOX via Schiff base reaction, which can self-assemble into nanoparticles (NPs) carrying some aldehyde groups. Subsequently, the amino groups of CD147 monoclonal antibody were bound to the aldehyde groups on the surface of ODEX-DOX NPs, resulting in acid-responsive and antibody-modified CD147-ODEX-DOX NPs with relatively small particle size and high DOX loading. FT-IR, UV-Vis, HPLC, and ¹H NMR were used to demonstrate the successful synthesis of polymer prodrug ODEX-DOX NPs and antibody-modified nanomedicine CD147-ODEX-DOX NPs. Dynamic light scattering (DLS) was used to evaluate the stability and the pH responsiveness of ODEX-DOX NPs in different media and tumour microenvironment. The in vitro total release content of DOX reached approximately 70% in PB 5.0 buffer solution after 103 h. Furthermore, the in vivo antitumour efficacy and biodistribution experiments confirmed that CD147-ODEX-DOX NPs could significantly inhibit the growth of HepG2 tumour. All of the results indicate that this acid-sensitive nanomedicine has higher safety and targeting effects. It promises to be an ideal strategy for future targeted drug delivery systems and anticancer therapies.

Effective mRNA Delivery by Condensation with Cationic Nanogels Incorporated into Liposomes

The challenge in effective delivery of mRNA has been a major hurdle in their development as therapeutics. Herein, we present that the incorporation of cationic nanogels as the condensing material for mRNA into liposomes enables stable and enhanced mRNA delivery to cells in vitro. We prepared dextran-based nanogel particles, which were surface functionalized with oligoarginine peptide (DNPR9) and complexed with mRNA for incorporation into liposomes (LipoDNPR9). The use of DNPR9 with the liposomes resulted in enhanced internalization, as well as a 4-fold increase in transfection of luciferase mRNA when treated with A549 cells in vitro, compared to control liposomes. The enhancement in transfection efficiency was also observed in various cell lines while causing low cytotoxicity. The versatility of the strategy was also investigated by applying DNPR9 for mRNA condensation to ionizable lipid particles, which resulted in an ∼55% increase in transfection. The current development based on nanogel-incorporated liposomes introduces an effective platform for mRNA delivery, while the condensation strategy using DNPR9 can be widely applied for various lipid-based formulations to enhance their efficacy.

New Methacrylated Biopolymer-Based Hydrogels as Localized Drug Delivery Systems in Skin Cancer Therapy

The aim of the present work was to obtain drug-loaded hydrogels based on combinations of dextran, chitosan/gelatin/xanthan, and poly (acrylamide) as a sustained and controlled release vehicle of Doxorubicin, a drug used in skin cancer therapy that is associated with severe side effects. Hydrogels for use as 3D hydrophilic networks with good manipulation characteristics were produced using methacrylated biopolymer derivatives and the methacrylate group's polymerization with synthetic monomers in the presence of a photo-initiator, under UV light stimulation (365 nm). Transformed infrared spectroscopy analysis (FT-IR) confirmed the hydrogels' network structure (natural-synthetic composition and photocrosslinking), while scanning electron microscopy (SEM) analysis confirmed the microporous morphology. The hydrogels are swellable in simulated biological fluids and the material's morphology regulates the swelling properties: the maximum swelling degree was obtained for dextran-chitosan-based hydrogels because of their higher porosity and pore distribution. The hydrogels are bioadhesive on a biological simulating membrane, and values for the force of detachment and work of adhesion are recommended for applications on skin tissue. The Doxorubicin was loaded into the hydrogels and the drug was released by diffusion for all the resulting hydrogels, with small contributions from the hydrogel networks' relaxation. Doxorubicin-loaded hydrogels are efficient on keratinocytes tumor cells, the sustained released drug interrupting the cells' division and inducing cell apoptosis; we recommend the obtained materials for the topical treatment of cutaneous squamous cell carcinoma.

Potentials of a Plasma-Aerosol System for Wound Healing Advanced by Drug Introduction: An In Vitro Study

Cold plasmas have found their application in a wide range of biomedical fields by virtue of their high chemical reactivity. In the past decades, many attempts have been made to use cold plasmas in wound healing, and within this field, many studies have focused on plasma-induced cell proliferation mechanisms. In this work, one step further has been taken to demonstrate the advanced role of plasma in wound healing. To this end, the simultaneous ability of plasma to induce cell proliferation and permeabilize treated cells has been examined in the current study. The driving force was to advance the wound healing effect of plasma with drug delivery. On this subject, we demonstrate in vitro the healing effect of Ar, Ar+N₂ plasma, and their aerosol counterparts. A systematic study has been carried out to study the role of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in cell adhesion, signaling, differentiation, and proliferation. An additional investigation was also performed to study the permeabilization of cells and the delivery of the modeled drug carrier fluorescein isothiocyanate (FITC) labeled dextran into cells upon plasma treatment. Short 35 s plasma treatments were found to promote fibroblast adhesion, migration, signaling, proliferation, and differentiation by means of reactive oxygen and nitrogen species (RONS) created by plasma and deposited into the cell environment. The impact of the plasma downstream products NO₂^- and NO₃^- on the expressions of the focal adhesion's genes, syndecans, and collagens was observed to be prominent. On the other hand, the differentiation of fibroblasts to myofibroblasts was mainly initiated by ROS produced by the plasma. In addition, the ability of plasma to locally permeabilize fibroblast cells was demonstrated. During proliferative cell treatment, plasma can simultaneously induce cell membrane permeabilization (d ∼ 7.3 nm) by the species OH and H₂O₂. The choice for a plasma or a plasma-aerosol configuration thus allows the possibility to change the spatial chemistry of drug delivery molecules and thus to locally deliver drugs. Accordingly, this study offers a pivotal step toward plasma-assisted wound healing advanced by drug delivery.

Host-guest drug delivery by β-cyclodextrin assisted polysaccharide vehicles: A review

Among different form of cyclodextrin (CD), β-CD has been taken a special attraction in pharmaceutical science due to lowest aqueous solubility and adequate cavity size. When β-CD forms inclusion complex with drugs then biopolymers such as polysaccharides in combination plays a vital role as a vehicle for safe release of drugs. It is noticed that, β-CD assisted polysaccharide-based composite achieves better drug release rate through host-guest mechanism. Present review is a critical analysis of this host-guest mechanism for release of drugs from polysaccharide supported β-CD inclusion complex. Various important polysaccharides such as cellulose, alginate, chitosan, dextran, etc. in relevant to drug delivery are logically compared in present review by their association with β-CD. Efficacy of mechanism of drug delivery by different polysaccharides with β-CD is analytically examined in schematic form. Drug release capacity at different pH conditions, mode of drug release, along with characterization techniques adopted by individual polysaccharide-based CD complexes are comparatively established in tabular form. This review may explore better visibility for researchers those are working in the area of controlled release of drugs by vehicle consist of β-CD associated polysaccharide composite through host-guest mechanism.

Past, present and future of biomedical applications of dextran-based hydrogels: A review

This review extensively surveys the biomedical applications of hydrogels containing dextran. Dextran has gained much attention as a biomaterial due to its distinctive properties such as biocompatibility, non-toxicity, water solubility and biodegradability. It has emerged as a critical constituent of hydrogels for biomedical applications including drug delivery devices, tissue engineering scaffolds and biosensor materials. The benefits, challenges and potential prospects of dextran-based hydrogels as biomaterials are highlighted in this review.

Dextran Formulations as Effective Delivery Systems of Therapeutic Agents

Dextran is by far one of the most interesting non-toxic, bio-compatible macromolecules, an exopolysaccharide biosynthesized by lactic acid bacteria. It has been extensively used as a major component in many types of drug-delivery systems (DDS), which can be submitted to the next in-vivo testing stages, and may be proposed for clinical trials or pharmaceutical use approval. An important aspect to consider in order to maintain high DDS' biocompatibility is the use of dextran obtained by fermentation processes and with a minimum chemical modification degree. By performing chemical modifications, artefacts can appear in the dextran spatial structure that can lead to decreased biocompatibility or even cytotoxicity. The present review aims to systematize DDS depending on the dextran type used and the biologically active compounds transported, in order to obtain desired therapeutic effects. So far, pure dextran and modified dextran such as acetalated, oxidised, carboxymethyl, diethylaminoethyl-dextran and dextran sulphate sodium, were used to develop several DDSs: microspheres, microparticles, nanoparticles, nanodroplets, liposomes, micelles and nanomicelles, hydrogels, films, nanowires, bio-conjugates, medical adhesives and others. The DDS are critically presented by structures, biocompatibility, drugs loaded and therapeutic points of view in order to highlight future therapeutic perspectives.

Orally administration of cerium oxide nanozyme for computed tomography imaging and anti-inflammatory/anti-fibrotic therapy of inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic nonspecific disease with unknown etiology. Currently, the anti-inflammatory therapeutic approaches have achieved a certain extent of effects in terms of inflammation alleviation. Still, the final pathological outcome of intestinal fibrosis has not been effectively improved yet.

RESULTS

In this study, dextran-coated cerium oxide (D-CeO₂) nanozyme with superoxide dismutase (SOD) and catalase (CAT) activities was synthesized by chemical precipitation. Our results showed that D-CeO₂ could efficiently scavenge reactive oxide species (ROS) as well as downregulate the pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, and iNOS) to protect cells from H₂O₂-induced oxidative damage. Moreover, D-CeO₂ could suppress the expression of fibrosis-related gene levels, such as α-SMA, and Collagen 1/3, demonstrating the anti-fibrotic effect. In both TBNS- and DSS-induced colitis models, oral administration of D-CeO₂ in chitosan/alginate hydrogel alleviated intestinal inflammation, reduced colonic damage by scavenging ROS, and decreased inflammatory factor levels. Notably, our findings also suggested that D-CeO₂ reduced fibrosis-related cytokine levels, predicting a contribution to alleviating colonic fibrosis. Meanwhile, D-CeO₂ could also be employed as a CT contrast agent for noninvasive gastrointestinal tract (GIT) imaging.

CONCLUSION

We introduced cerium oxide nanozyme as a novel therapeutic approach with computed tomography (CT)-guided anti-inflammatory and anti-fibrotic therapy for the management of IBD. Collectively, without appreciable systemic toxicity, D-CeO₂ held the promise of integrated applications for diagnosis and therapy, pioneering the exploration of nanozymes with ROS scavenging capacity in the anti-fibrotic treatment of IBD.

Carbohydrate Polymer-Based Targeted Pharmaceutical Formulations for Colorectal Cancer: Systematic Review of the Literature

Colon cancer is the third most diagnosed cancer worldwide, followed by lung and breast cancer. Conventional treatment methods are associated with numerous side effects and compliance issues. Thus, colon targeted drug delivery has gained much attention due to its evident advantages. Although many technologies have been explored, the use of pH-sensitive polymers, especially biodegradable polymers, holds exceptional promise. This review aims to collate research articles concerning recent advances in this area. A systematic search using multiple databases (Google Scholar, EMBASE, PubMed, MEDLINE and Scopus) was carried out following the preferred reported items for systematic reviews and meta-analyses (PRISMA) guidelines with an aim to explore the use of pH-sensitive carbohydrate polymers in developing colon targeted pharmaceutical formulations. Following screening and quality assessment for eligibility, 42 studies were included, exploring either single or a combination of carbohydrate polymers to develop targeted formulations for colon cancer therapy. Pectin (11) is the most widely used of these biopolymers, followed by chitosan (09), alginate (09) and guar gum (08). This systematic review has successfully gathered experimental evidence highlighting the importance of employing carbohydrate polymers in developing targeting formulations to manage colon cancer.

Anionically Functionalized Glycogen Encapsulates Melittin by Multivalent Interaction

We developed acid-functionalized glycogen conjugates as supramolecular carriers for efficient encapsulation and inhibition of a model cationic peptide melittin─the main component of honeybee venom. For this purpose, we synthesized and characterized a set of glycogens, functionalized to various degrees by several different acid groups. These conjugates encapsulate melittin up to a certain threshold amount, beyond which they precipitate. Computer simulations showed that sufficiently functionalized conjugates electrostatically attract melittin, resulting in its efficient encapsulation in a broad pH range around the physiological pH. Hemolytic assays confirmed in vitro that the effective inhibition of melittin's hemolytic activity occurs for highly functionalized samples, whereas no inhibition is observed when using low-functionalized conjugates. It can be concluded that functional glycogens are promising carriers for cationic molecular cargos or antidotes against animal venoms under conditions, in which suitable properties such as biodegradability and biocompatibility are crucial.

Construction of pH/reduction dual responsive MSN-HAgel containing HApt for tumor targeting carriers

In this study, a pH/reduction dual responsive carrier containing 42nt-nucleic acid HApt based on mesoporous silica nanoparticles (MSNs) was designed. Two kinds of low molecular weight oligomeric hyaluronic acid (HA) were used to graft onto MSN for better drug encapsulation. Crosslinked MSN-HA₃₀₀₀gel and MSN-HA₁₁₀₀₀gel were prepared by crosslinking the HA chain through the sulfhydrylization of the carboxyl group on the HA side chain. An appropriate amount of sulfhydryl nucleic acid (HApt-SH) was added during the crosslinking reaction, which realized the targeting ability and apoptosis function to cancer cells overexpressing the HER2 receptor. Crosslinked HA had a good effect on decreasing the side effect of DOX that the drug leakage was less than 20% under a normal body environment. However, it could realize rapid and efficient drug release in a tumor environment. As to the release of HApt, it exhibited a good response to GSH. The cytotoxicity test showed that HApt contained in HAgel had a great targeting effect and significant cytotoxicity to SKBR3 cells. As a whole, this MSN-HAgel enabled the combination of gene therapy and chemotherapy, showing the synergistic effect of “1 + 1 > 2”, providing a novel idea for cancer treatments.

A dual-responsive MSN-based nanocarrier for the combination of gene therapy and chemotherapy in cancer treatments.

Craft of Co-encapsulation in Nanomedicine: A Struggle To Achieve Synergy through Reciprocity

Achieving synergism, often by combination therapy via codelivery of chemotherapeutic agents, remains the mainstay of treating multidrug-resistance cases in cancer and microbial strains. With a typical core-shell architecture and surface functionalization to ensure facilitated targeting of tissues, nanocarriers are emerging as a promising platform toward gaining such synergism. Co-encapsulation of disparate theranostic agents in nanocarriers-from chemotherapeutic molecules to imaging or photothermal modalities-can not only address the issue of protecting the labile drug payload from a hostile biochemical environment but may also ensure optimized drug release as a mainstay of synergistic effect. However, the fate of co-encapsulated molecules, influenced by temporospatial proximity, remains unpredictable and marred with events with deleterious impact on therapeutic efficacy, including molecular rearrangement, aggregation, and denaturation. Thus, more than just an art of confining multiple therapeutics into a 3D nanoscale space, a co-encapsulated nanocarrier, while aiming for synergism, should strive toward achieving a harmonious cohabitation of the encapsulated molecules that, despite proximity and opportunities for interaction, remain innocuous toward each other and ensure molecular integrity. This account will inspect the current progress in co-encapsulation in nanocarriers and distill out the key points toward accomplishing such synergism through reciprocity.

Polysaccharide-Drug Conjugates: A Tool for Enhanced Cancer Therapy

Cancer is one of the most widespread deadly diseases, following cardiovascular disease, worldwide. Chemotherapy is widely used in combination with surgery, hormone and radiation therapy to treat various cancers. However, chemotherapeutic drugs can cause severe side effects due to non-specific targeting, poor bioavailability, low therapeutic indices, and high dose requirements. Several drug carriers successfully overcome these issues and deliver drugs to the desired sites, reducing the side effects. Among various drug delivery systems, polysaccharide-based carriers that target only the cancer cells have been developed to overcome the toxicity of chemotherapeutics. Polysaccharides are non-toxic, biodegradable, hydrophilic biopolymers that can be easily modified chemically to improve the bioavailability and stability for delivering therapeutics into cancer tissues. Different polysaccharides, such as chitosan, alginates, cyclodextrin, pullulan, hyaluronic acid, dextran, guar gum, pectin, and cellulose, have been used in anti-cancer drug delivery systems. This review highlights the recent progress made in polysaccharides-based drug carriers in anti-cancer therapy.

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.

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.

Cisplatin encapsulated nanoparticles from polymer blends for anti-cancer drug delivery

Synthesis of cubic nanostructure for cisplatin encapsulation.

Water Uptake as a Crucial Factor on the Properties of Cryogels of Gelatine Cross-Linked by Dextran Dialdehyde

We investigated the water sorption properties of macroporous cryogels of gelatine (Gel) and dextran dialdehyde (DDA) prepared via cryogelation at 260 K and following the freeze drying processes. Water vapour sorption isotherms for aerogels were studied at 293 K by two independent methods: static-gravimetric and dynamic vapour sorption (DVS) over a water activity range of 0.11-1.0. Experimental data were fitted by use of the Brunauer-Emmett-Teller (BET) and Guggenheim-Anderson-de Boer (GAB) models. The BET model (for a water activity range of 0.1 ≤ p/po ≤ 0.5) was used to calculate the sorption parameters of the studied cryogels (the monolayer capacity, surface area and energy of interaction). In comparison with BET, the GAB model can be applied for the whole range of water activities (0.1 ≤ p/po ≤ 0.95). This model gave an almost perfect correlation between the experimental and calculated sorption isotherms using nonlinear least squares fitting (NLSF). Confocal Laser Scanning Microscopy (CLSM) was used to confirm the structural differences between various DDA:Gel cryogel compositions. Thermogravimetric analysis and DSC data for aerogels DDA:Gel provided information regarding the bonded water loss, relative remaining water content of the material and the temperature of decomposition. Estimation of the amount of bound water in the cryogels after the freeze drying process as well as after the cycle of treatment of cryogels with high humidity and drying was performed using DSC. The results of the DSC determinations showed that cryogels with higher gelatin content had higher levels of bonded water.

Characterization of a nanoparticulate exopolysaccharide from Leuconostoc holzapfelii KM01 and its potential application in drug encapsulation

Fermentation of Lactic Acid Bacteria (LAB) is considered to be a sustainable approach for polysaccharide production. Herein, exopolysaccharide (EPS)-producing LAB strain KM01 was isolated from Thai fermented dessert, Khao Mak, which was then identified as Leuconostoc holzapfelii. High-performance anion-exchange chromatography, nuclear magnetic resonance spectroscopy and Fourier-transform infrared spectroscopy suggested that the KM01 EPS comprises α-1,6-linked glucosides. The molecular weight of KM01 EPS was around 500 kDa, but it can form large aggregates formation (MW > 2000 kDa) in an aqueous solution, judged by transmission electron microscopy and dynamic light scattering to be around 150 nm in size. Furthermore, this KM01 EPS form highly viscous hydrogels at concentrations above 5% (w/v). The formation of hydrogels and nanoparticle of KM01 EPS was found to be reversible. Finally, the suitability of KM01 EPS for biomedical applications was demonstrated by its lack of cytotoxicity and its ability to form complexes with quercetin. Unlike the common α-1,6-linked dextran, KM01 EPS can enhance the solubility of quercetin significantly.

Strategies for Preparing Different Types of Lipid Polymer Hybrid Nanoparticles in Targeted Tumor Therapy

At present, cancer is one of the most common diseases in the world, causing a large number of deaths and seriously affecting people's health. The traditional treatment of cancer is mainly surgery, radiotherapy or chemotherapy. Conventional chemotherapy is still an important treatment, but it has some shortcomings, such as poor cell selectivity, serious side effects, drug resistance and so on. Nanoparticle administration can improve drug stability, reduce toxicity, prolong drug release time, prolong system half-life, and bring broad prospects for tumor therapy. Lipid polymer hybrid nanoparticles (LPNs), which combine the advantages of polymer core and phospholipid shell to form a single platform, have become multi-functional drug delivery platforms. This review introduces the basic characteristics, structure and preparation methods of LPNs, and discusses targeting strategies of LPNs in tumor therapy in order to overcome the defects of traditional drug therapy.

Doxorubicin Loaded Dextran-coated Superparamagnetic Iron Oxide Nanoparticles with Sustained Release Property: Intracellular Uptake, Pharmacokinetics, and Biodistribution Study

BACKGROUND

Due to the short biological half-life and serious side effects (especially for heart and kidney), the application of Doxorubicin (Dox) in clinical therapy is strictly limited. To overcome these shortcomings, a novel sustained release formulation of doxorubicin-loaded dextran-coated superparamagnetic iron oxide nanoparticles (Dox-DSPIONs) was prepared.

OBJECTIVE

The purpose of this study was to evaluate the intracellular uptake behavior of Dox-DSPIONs and to investigate their pharmacokinetics and biodistribution properties.

METHOD

Confocal laser scanning microscopy was employed to study the intracellular uptake and release properties of Dox from Dox-DSPIONs in SMMC-7721 cells. Simple high-performance liquid chromatography with fluorescence detection (HPLC-FLD) method was established to study the pharmacokinetics and biodistribution properties of Dox-DSPIONs in vivo after intravenous administration and compared with free Dox.

RESULTS

Intracellular uptake experiment indicated that Dox could be released sustainedly from Dox-DSPIONs over time. The pharmacokinetics parameters displayed that the T1/2and AUC0-24h of Dox-DSPIONs were higher than those of free Dox, while the Cmax of Dox-DSPIONs was significantly lower than that of free drug. The biodistribution behaviors of the drug were altered by Dox-DSPIONs in mice, which showed obvious liver targeting, and significantly reduced the distribution of the drug in the heart and kidney.

CONCLUSION

Dox-DSPIONs have the sustained-release property in vitro and in vivo, which could significantly prolong blood circulation time, improve bioavailability, and reduce the side effects of Dox. Therefore, the novel formulation of the Dox-DSPIONs has the potential as a promising drug delivery system in cancer therapy.

Polymeric-based drug delivery systems for veterinary use: State of the art

One of the challenges to the success of veterinary pharmacotherapy is the limited number of drugs and dosage forms available exclusively to this market, due to the interspecies variability of animals, such as anatomy, physiology, pharmacokinetics, and pharmacodynamics. For this reason, studies in this area have become a highlight, since they are still scarce in comparison with those on human drug use. To overcome many limitations related to the bioavailability, efficacy, and safety of pharmacotherapy in animals, especially livestock and domestic animals, polymers-based drug delivery systems are promising tools if they guarantee greater selectivity and less toxicity in dosage forms. In addition, these tools may be developed according to the great interspecies variability. To contribute to these discussions, this paper provides an updated review of the major polymer-based drug delivery systems projected for veterinary use. Traditional and innovative drug delivery systems based on polymers are presented, with an emphasis on films, microparticles, micelles, nanogels, nanoparticles, tablets, implants and hydrogel-based drug delivery systems. We discuss important concepts for the veterinarian about the mechanisms of drug release and, for the pharmacist, the advantages in the development of pharmaceutical forms for the animal population. Finally, challenges and opportunities are presented in the field of pharmaceutical dosage forms for veterinary use in response to the interests of the pharmaceutical industry.

Sustained Release Systems for Delivery of Therapeutic Peptide/Protein

Peptide/protein therapeutics have been significantly applied in the clinical treatment of various diseases such as cancer, diabetes, etc. owing to their high biocompatibility, specificity, and therapeutic efficacy. However, due to their immunogenicity, instability stemming from its complex tertiary and quaternary structure, vulnerability to enzyme degradation, and rapid renal clearance, the clinical application of protein/peptide therapeutics is significantly confined. Though nanotechnology has been demonstrated to prevent enzyme degradation of the protein therapeutics and thus enhance the half-life, issues such as initial burst release and uncontrollable release kinetics are still unsolved. Moreover, the traditional administration method results in poor patient compliance, limiting the clinical application of protein/peptide therapeutics. Exploiting the sustained-release formulations for more controllable delivery of protein/peptide therapeutics to decrease the frequency of injection and enhance patient compliance is thus greatly meaningful. In this review, we comprehensively summarize the substantial advancements of protein/peptide sustained-release systems in the past decades. In addition, the advantages and disadvantages of all these sustained-release systems in clinical application together with their future challenges are also discussed in this review.

Selenium-Containing Polysaccharides—Structural Diversity, Biosynthesis, Chemical Modifications and Biological Activity

Selenosugars are a group of sugar derivatives of great structural diversity (e.g., molar masses, selenium oxidation state, and selenium binding), obtained as a result of biosynthesis, chemical modification of natural compounds, or chemical synthesis. Seleno-monosaccharides and disaccharides are known to be non-toxic products of the natural metabolism of selenium compounds in mammals. In the case of the selenium-containing polysaccharides of natural origin, their formation is also postulated as a form of detoxification of excess selenium in microorganisms, mushroom, and plants. The valency of selenium in selenium-containing polysaccharides can be: 0 (encapsulated nano-selenium), IV (selenites of polysaccharides), or II (selenoglycosides or selenium built into the sugar ring to replace oxygen). The great interest in Se-polysaccharides results from the expected synergy between selenium and polysaccharides. Several plant- and mushroom-derived polysaccharides are potent macromolecules with antitumor, immunomodulatory, antioxidant, and other biological properties. Selenium, a trace element of fundamental importance to human health, has been shown to possess several analogous functions. The mechanism by which selenium exerts anticancer and immunomodulatory activity differs from that of polysaccharide fractions, but a similar pharmacological effect suggests a possible synergy of these two agents. Various functions of Se-polysaccharides have been explored, including antitumor, immune-enhancement, antioxidant, antidiabetic, anti-inflammatory, hepatoprotective, and neuroprotective activities. Due to being non-toxic or much less toxic than inorganic selenium compounds, Se-polysaccharides are potential dietary supplements that could be used, e.g., in chemoprevention.

NMR analysis and molecular dynamics conformation of α-1,6-linear and α-1,3-branched isomaltose oligomers as mimetics of α-1,6-linked dextran

The conformational preferences of several α-1,6-linear and α-1,3-branched isomalto-oligosaccharides were investigated by NMR and MD-simulations. Right-handed helical structure contributed to the solution geometry in isomaltotriose and isomaltotetraose with one nearly complete helix turn and stabilizing intramolecular hydrogen bonds in the latter by MD-simulation. Decreased helix contribution was observed in α-1,3-glucopyranosyl- and α-1,3-isomaltosyl-branched saccharide chains. Especially the latter modification was predicted to cause a more compact structure consistent with literature rheology measurements as well as with published dextranase-resistant α-1,3-branched oligosaccharides. The findings presented here are significant because they shed further light on the conformational preference of isomalto-oligosaccharides and provide possible help for the design of dextran-based drug delivery systems or for the targeted degradation of capsular polysaccharides by dextranases in multi-drug resistant bacteria.

Natural polymeric nanocarriers in malignant glioma drug delivery and targeting

Among all central nervous diseases, malignant glioma is a crucial part that deserves more attention since high fatality and disability rate. There are several therapeutic strategies applied to the treatment of malignant glioma, especially certain chemotherapy-related treatments. However, the existence of the blood-brain barrier (BBB) seriously hinders the strategy's progress, so how to escape from the barriers is a fascinating question. Herein, we comprehensively discussed the details of malignant glioma and the BBB's functional morphology and summarized several routes bypassing the BBB. Additionally, since possessing excellent properties for drug delivery, we provided an insight into various promising natural polymeric materials and highlighted their applications in the treatment of malignant glioma.

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.

Phytochemical delivery through nanocarriers: a review

In recent times, phytochemicals encapsulated or conjugated with nanocarriers for delivery to the specific sites have gained considerable research interest. Phytochemicals are mostly plant secondary metabolites which reported to be beneficial for human health and in disease theraphy. However, these compound are large size and polar nature of these compounds, make it difficult to cross the blood-brain barrier (BBB), endothelial lining of blood vessels, gastrointestinal tract and mucosa. Moreover, they are enzymatically degraded in the gastrointestinal tract. Therefore, encapsulation or conjugation of these compounds with nanocrriers could be an alternate way to enhance their bioefficacy by influencing their gastrointestinal stability, rate of absorption and dispersion. This review presents an overview of nanocarriers alternatives which improves therapeutic value and avoid toxicity, by releasing bioactive compounds specifically at target tissues with enhanced stability and bioavailability. Future investigations may emphasize on deciphering the structural changes in nanocarriers during digestion and absorption, the difference between in-vitro and in-vivo digestion simulations, and impact of nanocarriers on the metabolism of phytochemicals.

Transdermal delivery of FITC-Dextrans with different molecular weights using radiofrequency microporation

Background

Transdermal delivery is of great importance for the effective delivery of bioactive or therapeutic agents into a body. The microporation device based on radiofrequency can be used to enhance delivery efficiency by removing the epidermis layer.

Methods

The micropores were developed on pig skin and human cadaver skin with dermal and epidermal layers by the microporation device. The regeneration of micropores in the human cadaver skin caused by microporation was confirmed using an optical microscope and haematoxylin/eosin (H&E) staining. The permeability of fluorescein isothiocyanate-dextrans (FITC-dextrans) with different molecular weights through the pig and human cadaver skins were measured using Franz diffusion cell.

Results

The optical image and histological analysis confirmed that the micropores on the skin were recovered over time. The enhanced permeability through micropores was confirmed by Franz diffusion cell. The lower molecular weight of FITC-dextran permeated more on both human and pig skin. In addition, the permeation rate was higher in pig skin than in human skin.

Conclusions

We believe that the microporation device can be used as a potential technique for effective transdermal drug delivery.

Investigation of Dextran-Coated Superparamagnetic Nanoparticles for Targeted Vinblastine Controlled Release, Delivery, Apoptosis Induction, and Gene Expression in Pancreatic Cancer Cells

In the current study, the surface of superparamagnetic iron oxide (SPION) was coated with dextran (DEX), and conjugated with folic acid (FA), to enhance the targeted delivery and uptake of vinblastine (VBL) in PANC-1 pancreatic cancer cells. Numerous analyses were performed to validate the prepared FA-DEX-VBL-SPION, such as field emission scanning transmission electron microscopy, high-resolution transmission electron microscopy, dynamic light scattering (DLS), Zeta Potential, Fourier transform infrared spectroscopy, and vibrating sample magnetometry (VSM). The delivery system capacity was evaluated by loading and release experiments. Moreover, in vitro biological studies, including a cytotoxicity study, cellular uptake assessment, apoptosis analysis, and real-time PCR, were carried out. The results revealed that the obtained nanocarrier was spherical with a suitable dispersion and without visible aggregation. Its average size, polydispersity, and zeta were 74 ± 13 nm, 0.080, and −45 mV, respectively. This dual functional nanocarrier also exhibited low cytotoxicity and a high apoptosis induction potential for successful VBL co-delivery. Real-time quantitative PCR analysis demonstrated the activation of caspase-3, NF-1, PDL-1, and H-ras inhibition, in PANC-1 cells treated with the FA-VBL-DEX-SPION nanostructure. Close inspection of the obtained data proved that the FA-VBL-DEX-SPION nanostructure possesses a noteworthy chemo-preventive effect on pancreatic cancer cells through the inhibition of cell proliferation and induction of apoptosis.

Liquid chromatography/tandem mass spectrometric analysis of penicillamine for its pharmacokinetic evaluation in dogs

Copper storage disease occurs in multiple dog breeds and is one of the most common causes of chronic hepatitis in this species. The disease is caused by hereditary defects in copper metabolism in conjunction with high dietary copper levels. The progressive copper accumulation leads to hepatitis, cirrhosis, and eventually death if left untreated. Copper chelators are critical in modulating the effects of this disease. It is therefore of significant practicality to understand the pharmacokinetic (PK) parameters of chelating agents, particularly since they are oftentimes quite expensive. A liquid chromatography-tandem mass spectrometric (LC/MS/MS) method was developed to measure plasma levels of one of the most common chelators, d-penicillamine. The compound was discovered to exist in two forms, monomeric and dimeric, and various chemical derivatizations were tried to force the compound into one form or the other. Eventually, the simplest approach was individual determination of penicillamine and its dimer, with summation of the two quantities. This enabled determination of canine PK parameters for penicillamine based on comparison of oral and intravenous administration of the drug, including time to maximum drug level (Tmax), concentration at maximum (Cmax), clearance (Cls) and volume of distribution (Vdss). The drug was found to exist predominantly in the dimeric form in plasma, which is incapable of chelating copper owing to lack of free sulfhydryl groups and must therefore provide a storage form of the drug in equilibrium with its monomeric form in vivo. Mechanisms are discussed for the electrospray-induced fragmentation of penicillamine as well as of its dimer.

Glycogen as an advantageous polymer carrier in cancer theranostics: Straightforward in vivo evidence

As a natural polysaccharide polymer, glycogen possesses suitable properties for use as a nanoparticle carrier in cancer theranostics. Not only it is inherently biocompatible, it can also be easily chemically modified with various moieties. Synthetic glycogen conjugates can passively accumulate in tumours due to enhanced permeability of tumour vessels and limited lymphatic drainage (the EPR effect). For this study, we developed and examined a glycogen-based carrier containing a gadolinium chelate and near-infrared fluorescent dye. Our aim was to monitor biodistribution and accumulation in tumour-bearing rats using magnetic resonance and fluorescence imaging. Our data clearly show that these conjugates possess suitable imaging and tumour-targeting properties, and are safe under both in vitro and in vivo conditions. Additional modification of glycogen polymers with poly(2-alkyl-2-oxazolines) led to a reduction in the elimination rate and lower uptake in internal organs (lower whole-body background: 45% and 27% lower MRI signals of oxazoline-based conjugates in the liver and kidneys, respectively compared to the unmodified version). Our results highlight the potential of multimodal glycogen-based nanopolymers as a carrier for drug delivery systems in tumour diagnosis and treatment.