Search Results (162)

Superparamagnetic iron oxide (SPIO) nanoparticles are a promising platform for drug delivery and magnetic resonance imaging (MRI). However, complement activation and immune recognition remain major barriers to their clinical translation. Previously, we reported that dextran-coated SPIO nanoworms (NWs) trigger potent complement activation and infusion reactions. Here, we systematically map the temporal sequence of immune events following SPIO NW administration, including C3 opsonization, granulocyte uptake, and cytokine release. In both in vitro and in vivo models, C3 deposition occurred rapidly, peaking at approximately 5 min post-incubation or post-injection. Higher Fe/plasma ratios led to reduced C3 deposition per particle, although the absolute amount of C3 bound was greater in vivo than in vitro. Notably, C3 dissociation from the particle surface exhibited a consistent half-life of ~14 min, independent of the NW injected dose and circulation time. Immune uptake by blood granulocytes was delayed relative to opsonization, becoming prominent only at 60 min post-injection. Further, cytokine release, measured by plasma IL-6 levels, displayed an even slower profile, with peak expression at 6 h post-injection. Together, these results reveal a distinct sequential immune response to SPIO NWs: rapid C3 opsonization, delayed cellular uptake, and late cytokine response. Understanding these dynamics provides a basis for developing strategies to inhibit complement activation and improve the hemocompatibility of SPIO-based theranostic agents. Full article

Global concerns about environmental pollution, poor waste management, and the rise in antimicrobial resistance due to uncontrolled antibiotic use have driven researchers to seek alternative, multifaceted solutions. Plants, animals, microorganisms, and their processing wastes serve as valuable sources of natural biopolymers and bioactive compounds. Through nanotechnology, these can be assembled into formulations with enhanced antimicrobial properties, high safety, and low toxicity. This review explores polysaccharides, including chitosan, alginate, starch, pectin, cellulose, hemicellulose, gums, carrageenan, dextran, pullulan, and hyaluronic acid, used in nanotechnology, highlighting their advantages and limitations as nanocarriers. Addressing the global urgency for alternative antimicrobials, we examined natural compounds derived from plants, microorganisms, and animals, such as phytochemicals, bacteriocins, animal antimicrobial peptides, and proteins. Focusing on their protection and retained activity, this review discusses polysaccharide-based nanoformulations with natural antimicrobials, including nanoparticles, nanoemulsions, nanocapsules, nanoplexes, and nanogels. Special emphasis is placed on strategies and formulations for the encapsulation, entrapment, and conjugation of natural compounds using polysaccharides as protective carriers and delivery systems, including a brief discussion on their future applications, prospects, and challenges in scaling up. Full article

In this study, we report the synthesis and characterization of Fe₃O₄ nanoparticles coated with dextran. The structural and optical properties of the Dx:Fe₃O₄ synthesized composites were investigated by Fourier Transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and UV–Vis absorption spectroscopy. For the first time in this paper, the photophysics of Dx:Fe₃O₄ composites in water is studied using fluorescence and phosphorescence molecular spectrometry. An analysis of the absorption spectra of the Dx:Fe₃O₄ composite reveals the broad absorption bands with maxima at wavelengths of 227 nm, 264 nm, and 340 nm. Dx:Fe₃O₄ composite nanoparticles in water exhibit strong fluorescence with a quantum yield of 0.24% in contrast to 0.07% for dextran. Phosphorescence spectra confirm the formation of new emission bands within the Dx:Fe₃O₄ solution evidenced by the maxima shift for both dextran and Dx:Fe₃O₄ composites. Full article

Stem cells therapies offer a promising approach in translational oncology, as well as in regenerative medicine due to the tropism of these cells to the damage site. To track the distribution of stem cells, the latter could be labeled by MRI-sensitive superparamagnetic (SPM) iron oxide nanoparticles. In the current study, magnetic properties of the magnetic nanoparticles (MNPs) incorporated into the bone marrow-derived fetal mesenchymal stem cells (FetMSCs) were evaluated employing nonlinear magnetic response measurements. Synthesized dextran-coated iron oxide nanoparticles were additionally characterized by X-ray diffraction, transmission electron microscopy, and dynamic light scattering. The MNP uptake by the FetMSCs 24 h following coincubation was studied by longitudinal nonlinear response to weak alternating magnetic field with registration of the second harmonic of magnetization. Subsequent data processing using a formalism based on the numerical solution of the Fokker–Planck kinetic equation allowed us to determine magnetic and dynamic parameters and the state of MNPs in the cells, as well as in the culture medium. It was found that MNPs formed aggregates in the culture medium; they were absorbed by the cells during coincubation. The aggregates exhibited SPM regime in the medium, and the parameters of the MNP aggregates remained virtually unchanged in the cells, indicating the preservation of the aggregation state of MNPs inside the cells. This implies also the preservation of the organic shell of the nanoparticles inside FetMSCs. The accumulation of MNPs by mesenchymal stem cells gradually increased with the concentration of MNPs. Thus, the study confirmed that the labeling of MSCs with MNPs is an effective method for subsequent cell tracking as incorporated nanoparticles retain their magnetic properties. Full article

The colloidal long-storage stability of nanosized drugs is a crucial factor for pharmacology, as they require much time for robust estimation. The application of bioavailable magnetic nanosuspensions in theranostics is limited by incomplete information about their colloidal stability in the internal media of human organisms. A method for the accelerated temperature stress “aging” of magnetic nanosized suspensions is proposed for the rapid assessment and prediction of the colloidal stability over time of nanosized iron oxide suspensions stabilized by albumin HSA. Colloidal stability is assessed using dynamic light scattering (DLS), fluorescence spectroscopy, electrophoresis, and ion monitoring methods during short- and long-term storage. Rapid assessment is achieved by short high-temperature (70 °C) processing of carboxymethyl-dextran-coated nanosol in the presence of albumin. The role of albumin in the sustained stability of superparamagnetic iron oxide particles (SPIONs) was studied under conditions mimicking blood plasma (pH = 7.4) and endolysosomal cell compartments (pH = 5.5). According to the fluorescence quenching and DLS data, colloidal stability is ensured by the formation of an HSA corona on carboxymethyl-dextran-coated SPIONs and their process of clustering. In the presence of albumin, the colloidal stability of nanoparticles is shown to increase from 80 to 121 days at a storage temperature of 8 °C The prognostic shelf life of magnetic nanosol is estimated by calculating the Van’t Hoff’s relation for the rate of chemical reactions. The validity of using the Van’t Hoff’s rule is confirmed by the agreement of the calculated activation energy at 8 °C and 70 °C. The developed method of the accelerated aging of nanoparticles can not only be employed for the estimation of the shelf life of magnetic nanoparticles coated with HSA in vitro but also for assessing the stability of SPIONs applied in vivo. Full article

Rare earth metal nanoparticles, some of which are already widely used in medicine, are of growing interest in the modern scientific community. One of the promising rare earth metals for biomedical applications is cerium, specifically its oxide form, which is characterized by a higher level of stability and safety. According to a number of studies, cerium dioxide has a wide range of biological effects (regenerative, antimicrobial, antioxidant, antitumor), which justifies the interest of its potential application in medicine. However, these effects and their intensity vary significantly across a number of studies. Since cerium dioxide was used in these studies, it can be assumed that not only is the chemical formula important, but also the physicochemical parameters of the nanoparticles obtained, and consequently the methods of their synthesis and modification with the use of excipients. In this review, we considered the possibilities of using a number of excipients (polyacrylate, polyvinylpyrrolidone, dextran, hyaluronic acid, chitosan, polycarboxylic acids, lecithin, phosphatidylcholine) in the context of preserving the biological effects of cerium dioxide and its physicochemical properties, as well as the degree of study of these combinations from the point of view of the prospect of creating drugs based on it for biomedical applications. Full article

Boron Neutron Capture Therapy (BNCT) is a therapeutic approach used to treat malignancies that are difficult to localise and typically inoperable. This therapy involves two stages: the administration of the boron (¹⁰B) isotope, which selectively enters cancer cells without affecting healthy tissue, followed by irradiation of the tumour with a neutron beam. In this study, boron carbide (B₄C), a ceramic material with exceptional physical and chemical properties, was used as a nanoparticle platform for BNCT. The surface of the boron carbide nanoparticles was optimised by modifying them with compounds such as dextrin, dextran T70, sorbitol, lysine, and arginine. Boron carbide was synthesised directly from boron and carbon and then subjected to grinding, washing, and centrifugation. The unmodified and modified samples were analysed for their particle size, zeta potential, and toxicity against glioblastoma T98G cells. Additionally, FTIR spectroscopy confirmed the successful surface modifications. The results demonstrate that boron carbide, as a ceramic material, can be effectively functionalised with biocompatible compounds. Among the tested modifications, B₄C-dextrin and B₄C-dextran T70 exhibited the highest toxicity towards cancer cells, demonstrating the potential of ceramic platforms in biomedical applications. Full article

Background/Objectives: Glioblastoma is the most common and lethal primary brain tumor. Patients often suffer from tumor- and treatment induced vasogenic edema, with devastating neurological consequences. Intracranial edema is effectively treated with dexamethasone. However, systemic dexamethasone requires large doses to surpass the blood brain barrier in therapeutic quantities, which is associated with significant side effects. The aim of this study was to investigate a biodegradable, dextran-hydroxyethyl methacrylate (dex-HEMA) based hydrogel, containing polymeric micelles loaded with dexamethasone and liposomes encapsulating dexamethasone phosphate for localized and prolonged delivery. Methods: Poly(ethylene glycol)-b-poly(N-2-benzoyloxypropyl methacrylamide (mPEG-b-p(HPMA-Bz)) micelles were loaded with dexamethasone and characterized. The dexamethasone micelles, together with dexamethasone phosphate liposomes, were dispersed in an aqueous dex-HEMA solution followed by radical polymerization using a photoinitiator in combination with light. The kinetics and mechanisms of drug release from this hydrogel were determined. Results: The diameter of the nanoparticles was larger than the mesh size of the hydrogel, rendering them immobilized in the polymer network. The micelles immediately released free dexamethasone from the hydrogel for two weeks. The dexamethasone phosphate loaded in the liposomes was not released until the gel degraded and intact liposomes were released, starting after 15 days. The different modes of release result in a biphasic and sequential release profile of dexamethasone followed by dexamethasone phosphate liposomes. Conclusions: The results show that this hydrogel system loaded with both dexamethasone polymeric micelles and dexamethasone phosphate loaded liposomes has potential as a local delivery platform for the sequential release of dexamethasone and dexamethasone phosphate, for the intracranial treatment of glioblastoma associated edema. Full article

This study addresses issues in developing spatially controlled magnetic fields for particle guidance, synthesizing biocompatible and chemically stable MNPs and enhancing their specificity to pathological cells through chemical modifications, developing personalized adjustments, and highlighting the potential of tumor-on-a-chip systems, which can simulate tissue environments and assess drug efficacy and dosage in a controlled setting. The research focused on two MNP types, uncoated magnetite nanoparticles (mMNPs) and carboxymethyl dextran coated superparamagnetic nanoparticles (CD-SPIONs), and evaluated their transport properties in microfluidic systems and porous media. The original uncoated mMNPs of bimodal size distribution and the narrow size distribution of the fractions (23 nm and 106 nm by radii) were demonstrated to agglomerate in magnetically driven microfluidic flow, forming a stable stationary web consisting of magnetic fibers within 30 min. CD-SPIONs were demonstrated to migrate in agar gel with the mean pore size equal to or slightly higher than the particle size. The migration velocity was inversely proportional to the size of particles. No compression of the gel was observed under the magnetic field gradient of 40 T/m. In the brain tissue, particles of sizes 220, 350, 820 nm were not penetrating the tissue, while the compression of tissue was observed. The particles of 95 nm size penetrated the tissue at the edge of the sample, and no compression was observed. For all particles, movement through capillary vessels was observed. Full article

Background: Resveratrol (RSV) is a natural polyphenol that offers antioxidant, anti-inflammatory, and chemopreventive benefits. This project determined the ability of RSV-loaded nanoparticles (NP) to inhibit the growth of lung tumor spheroids in vitro. Methods: RSV was encapsulated in NP comprised of the biodegradable polymer, acetalated dextran. A549 lung cancer cells in two-dimensional and three-dimensional cell culture models were exposed to free RSV and RSV NP to evaluate their effect on cell proliferation and spheroid formation and growth. For prevention studies, spheroids were exposed to free RSV and RSV NP on day 0, and for treatment studies, spheroids were dosed with the same formulations on day 5 after the spheroids had fully formed. Results: The resulting RSV NP were 200 nm in diameter with neutral surface charge and exhibited the ability to control the release of RSV in vitro based on environmental pH. In comparison to free RSV, the RSV NP exerted a greater inhibitory effect on the proliferation and growth of cancer cells and spheroids. Conclusions: RSV NP have the potential to be used as a chemopreventive agent for lung cancer. Full article

Wound healing involves a sophisticated biological process that relies on ideal conditions to advance through various stages of repair. Modern wound dressings are designed to imitate the natural surroundings around cells and offer properties such as moisture regulation, strength, and antimicrobial defense to boost healing. A recent research project unveiled a new type of gelatin (Gel)/dextran (Dex) hydrogels, linked through Diels-Alder (D-A) reactions, loaded with silver nanoparticles (Ag-NPs) for cutting-edge wound treatment. Gel and Dex were chemically modified to form the hydrogels via the D-A reaction. The hydrogels were enriched with Ag-NPs at varying levels. Thorough analyses of the hydrogels using methods like NMR, FT-IR, and SEM were carried out to assess their structure and nanoparticle integration. Rheological tests displayed that the hydrogels had favorable mechanical attributes, particularly when Ag-NPs were included. The hydrogels demonstrated controlled swelling, responsiveness to pH changes, and were non-toxic. Testing against E. coli showcased the strong antibacterial activity of the nanocomposite hydrogels in a concentration-dependent manner. This investigation showcased the promise of these bioactive nanocomposite hydrogels in promoting speedy wound healing by maintaining a moist environment, offering an antimicrobial shield, and ensuring mechanical support at the wound site. Full article

Zeolitic imidazolate framework-8 (ZIF-8) nanoparticles (NPs) are gaining traction in tumor theranostics for their effectiveness in encapsulating both imaging agents and therapeutic drugs. While typically, similar hydrophilic molecules are encapsulated in either pure aqueous or organic environments, few studies have explored co-encapsulation of chemotherapeutic drugs and imaging agents with varying hydrophilicity and, consequently, constructed multifunctional ZIF-8 composite NPs for acid-responsive, near-infrared fluorescence imaging/chemotherapy combined tumor theranostics. Here, we present a one-pot method for the synthesis of uniform Cy5.5&DOX@ZIF-8 nanoparticles in mixed solvents, efficiently achieving simultaneous encapsulation of hydrophilic doxorubicin (DOX) and hydrophobic Cyanine-5.5 (Cy5.5). Surface decoration with dextran (Dex) enhanced colloidal stability and biocompatibility. The method significantly facilitated co-loading of Cy5.5 dyes and DOX drugs, endowing the composite NPs with notable fluorescent imaging capabilities and pH-responsive chemotherapy capacities. In vivo near-infrared fluorescence (NIRF) imaging in A549 tumor-bearing mice demonstrated significant accumulation of Cy5.5 at tumor sites due to enhanced permeability and retention (EPR) effects, with fluorescence intensities approximately 48-fold higher than free Cy5.5. Enhanced therapeutic efficiency was observed in composite NPs compared to free DOX, validating tumor-targeted capability. These findings suggest ZIF-8-based nanomedicines as promising platforms for multifunctional tumor theranostics. Full article

Purpose of the study: the creation of a dextran coating on cerium oxide crystals using different ratios of cerium and dextran to synthesize nanocomposites, and the selection of the best nanocomposite to develop a nanodrug that accelerates quality wound healing with a new type of antimicrobial effect. Materials and methods: Nanocomposites were synthesized using cerium nitrate and dextran polysaccharide (6000 Da) at four different initial ratios of Ce(NO₃)₃x6H₂O to dextran (by weight)—1:0.5 (Ce0.5D); 1:1 (Ce1D); 1:2 (Ce2D); and 1:3 (Ce3D). A series of physicochemical experiments were performed to characterize the created nanocomposites: UV-spectroscopy; X-ray phase analysis; transmission electron microscopy; dynamic light scattering and IR-spectroscopy. The biomedical effects of nanocomposites were studied on human fibroblast cell culture with an evaluation of their effect on the metabolic and proliferative activity of cells using an MTT test and direct cell counting. Antimicrobial activity was studied by mass spectrometry using gas chromatography–mass spectrometry against E. coli after 24 h and 48 h of co-incubation. Results: According to the physicochemical studies, nanocrystals less than 5 nm in size with diffraction peaks characteristic of cerium dioxide were identified in all synthesized nanocomposites. With increasing polysaccharide concentration, the particle size of cerium dioxide decreased, and the smallest nanoparticles (<2 nm) were in Ce2D and Ce3D composites. The results of cell experiments showed a high level of safety of dextran nanoceria, while the absence of cytotoxicity (100% cell survival rate) was established for Ce2D and C3D sols. At a nanoceria concentration of 10⁻² M, the proliferative activity of fibroblasts was statistically significantly enhanced only when co-cultured with Ce2D, but decreased with Ce3D. The metabolic activity of fibroblasts after 72 h of co-cultivation with nano composites increased with increasing dextran concentration, and the highest level was registered in Ce3D; from the dextran group, differences were registered in Ce2D and Ce3D sols. As a result of the microbiological study, the best antimicrobial activity (bacteriostatic effect) was found for Ce0.5D and Ce2D, which significantly inhibited the multiplication of E. coli after 24 h by an average of 22–27%, and after 48 h, all nanocomposites suppressed the multiplication of E. coli by 58–77%, which was the most pronounced for Ce0.5D, Ce1D, and Ce2D. Conclusions: The necessary physical characteristics of nanoceria–dextran nanocomposites that provide the best wound healing biological effects were determined. Ce2D at a concentration of 10⁻³ M, which stimulates cell proliferation and metabolism up to 2.5 times and allows a reduction in the rate of microorganism multiplication by three to four times, was selected for subsequent nanodrug creation. Full article

A polydopamine polyelectrolyte hydrogel was developed by ionic crosslinking dextran sulfate with a copolymer of polyethyleneimine and polydopamine. Gelation was promoted by the slow hydrolysis of glucono-δ-lactone. Within this hydrogel, silver nanoparticles were generated in situ, ranging from 25 nm to 200 nm in size. The antibacterial activity of the hydrogel was proportional to the quantity of silver nanoparticles produced, increasing as the nanoparticle count rose. The hydrogels demonstrated broad-spectrum antibacterial efficacy at concentrations up to 10⁸ cells/mL for P. aeruginosa, K. pneumoniae, E. coli and S. aureus, the four most prevalent bacterial pathogens in chronic septic wounds. In ex vivo studies on human skin, biocompatibility was enhanced by the presence of polydopamine. Dextran sulfate is a known irritant, but formulations with polydopamine showed improved cell viability and reduced levels of the inflammatory biomarkers IL-8 and IL-1α. Silver nanoparticles can inhibit cell migration, but an ex vivo human skin study showed significant re-epithelialization in wounds treated with hydrogels containing silver nanoparticles. Full article

Photodynamic therapy (PDT) is a non-invasive anticancer treatment that uses special photosensitizer molecules (PS) to generate singlet oxygen and other reactive oxygen species (ROS) in a tissue under excitation with red or infrared light. Though the method has been known for decades, it has become more popular recently with the development of new efficient organic dyes and LED light sources. Here we introduce a ternary nanocomposite: water-soluble star-like polymer/gold nanoparticles (AuNP)/temoporfin PS, which can be considered as a third-generation PDT system. AuNPs were synthesized in situ inside the polymer molecules, and the latter were then loaded with PS molecules in an aqueous solution. The applied method of synthesis allows precise control of the size and architecture of polymer nanoparticles as well as the concentration of the components. Dynamic light scattering confirmed the formation of isolated particles (120 nm diameter) with AuNPs and PS molecules incorporated inside the polymer shell. Absorption and photoluminescence spectroscopies revealed optimal concentrations of the components that can simultaneously reduce the side effects of dark toxicity and enhance singlet oxygen generation to increase cancer cell mortality. Here, we report on the optical properties of the system and detailed mechanisms of the observed enhancement of the phototherapeutic effect. Combinations of organic dyes with gold nanoparticles allow significant enhancement of the effect of ROS generation due to surface plasmonic resonance in the latter, while the application of a biocompatible star-like polymer vehicle with a dextran core and anionic polyacrylamide arms allows better local integration of the components and targeted delivery of the PS molecules to cancer cells. In this study, we demonstrate, as proof of concept, a successful application of the developed PDT system for in vitro treatment of triple-negative breast cancer cells under irradiation with a low-power LED lamp (660 nm). We consider the developed nanocomposite to be a promising PDT system for application to other types of cancer. Full article