Search Results (171)

Carbon dots (CDs) have emerged as a distinct class of fluorescent nanomaterials distinguished by their tunable physicochemical properties, ultrasmall size, exceptional photoluminescence, versatile surface chemistry, high biocompatibility, and chemical stability, positioning them as promising candidates for biomedical applications ranging from sensing and imaging to drug delivery and theranostics. As CDs increasingly transition toward biological and clinical use, a fundamental understanding of their interactions with biological membranes becomes essential, as cellular membranes govern nanoparticle uptake, intracellular transport, and therapeutic performance. Model membrane systems, such as phospholipid vesicles and liposomes, offer controllable platforms to elucidate CD-membrane interactions by isolating key physicochemical variables otherwise obscured in complex biological environments. Recent studies demonstrate that CD surface chemistry, charge, heteroatom doping, size, and hydrophobicity, together with membrane composition, packing density, and phase behavior, dictate nanoparticle adsorption, insertion, diffusion, and membrane perturbation. In addition, CD-liposome hybrid systems have gained momentum as multifunctional nanoplatforms that couple the fluorescence and traceability of CDs with the encapsulation capacity and biocompatibility of lipid vesicles, enabling imaging-guided drug delivery and responsive theranostic systems. This review consolidates current insights into the mechanistic principles governing CD interactions with model membranes and highlights advances in CD-liposome hybrid nanostructures. By bridging fundamental nanoscale interactions with translational nanomedicine strategies, this work provides a framework for the rational design of next-generation CD-based biointerfaces with optimized structural, optical, and biological performance. Full article

The Clausius–Mossotti (CM) factor underpins the theoretical description of dielectrophoresis (DEP) and is widely used in micro- and nano-scale systems for frequency-dependent particle and cell manipulation. It has further been proposed as an “electrophysiology Rosetta Stone” capable of linking DEP spectra to intrinsic cellular electrical properties. In this paper, the mathematical foundations and interpretive limits of this proposal are critically examined. By analyzing contrast factors derived from Laplace’s equation across multiple physical domains, it is shown that the CM functional form is a universal consequence of geometry, material contrast, and boundary conditions in linear Laplacian fields, rather than a feature unique to biological systems. Key modelling assumptions relevant to DEP are reassessed. Deviations from spherical symmetry lead naturally to tensorial contrast factors through geometry-dependent depolarisation coefficients. Complex, frequency-dependent CM factors and associated relaxation times are shown to inevitably arise from the coexistence of dissipative and storage mechanisms under time-varying forcing, independent of particle composition. Membrane surface charge influences DEP response through modified interfacial boundary conditions and effective transport parameters, rather than by introducing an independent driving mechanism. These results indicate that DEP spectra primarily reflect boundary-controlled field–particle coupling. From an inverse-problem perspective, this places fundamental constraints on parameter identifiability in DEP-based characterization. The CM factor remains a powerful and general modelling tool for micromachines and microfluidic systems, but its interpretive scope must be understood within the limits imposed by Laplacian field theory. Full article

Valsartan (Val)—a lipophilic non-peptide angiotensin II type 1 receptor antagonist—is highly effective against hypertension and displaying limited solubility in water (3.08 μg/mL), thereby resulting in low oral bioavailability (23%). The limited water solubility of antihypertensive drugs can pose a challenge, particularly for rapid and precise administration. Herein, we synthesize and characterize valsartan-containing silver nanoparticles (Val-AgNPs) using Mangifera indica leaf extracts. The physicochemical, structural, thermal, and pharmacological properties of these nano-conjugates were established through various analytical and structural tools. The spectral shifts in both UV-visible and FTIR analyses indicate a successful interaction between the valsartan molecule and the silver nanoparticles. The resulting nano-conjugates are spherical and within the size range of 30–60 nm as revealed in scanning electron-EDS and atomic force micrographs. The log-normal distribution of valsartan-loaded nanoparticles, with a size range of 30 to 60 nm and a mode of 54 nm, indicates a narrow, monodisperse, and highly uniform particle size distribution. This is a favorable characteristic for drug delivery systems, as it leads to enhanced bioavailability and a consistent performance. Dynamic Light Scattering (DLS) analysis of the Val-AgNPs indicates a polydisperse sample with a tendency toward aggregation, resulting in larger effective sizes in the suspension compared to individual nanoparticles. The accompanying decrease in zeta potential (to −19.5 mV) and conductivity further supports the idea that the surface chemistry and stability of the nanoparticles changed after conjugation. Differential scanning calorimetry (DSC) demonstrated the melting onset of the valsartan component at 113.99 °C. The size-dependent densification of the silver nanoparticles at 286.24 °C correspond to a size range of 40–60 nm, showing a significant melting point depression compared to bulk silver due to nanoscale effects. The shift in Rf for pure valsartan to Val-AgNPs suggests that the interaction with the AgNPs alters the compound’s overall polarity and/or its interaction with the stationary phase, complimented in HPTLC and HPLC analysis. The stability and offloading behavior of Val-AgNPs was observed at pH 6–10 and in 40% and 80% MeOH. In addition, Val-AgNPs did not reveal hemolysis or significant alterations in blood cell indices, confirming the safety of the nano-conjugates for biological application. In conclusion, these findings provide a comprehensive characterization of Val-AgNPs, highlighting their potential for improved drug delivery applications. Full article

Temperature-responsive hydrogels are sophisticated stimuli-responsive biomaterials that undergo rapid, reversible sol–gel phase transitions in response to subtle thermal stimuli, most notably around physiological temperature. This inherent thermosensitivity enables non-invasive, precise spatiotemporal control of material properties and bioactive payload release, rendering them highly promising for advanced biomedical applications. This review critically surveys recent advances in the design, synthesis, and translational potential of thermo-responsive hydrogels, emphasizing nanoscale and hybrid architectures optimized for superior tunability and biological performance. Foundational systems remain dominated by poly(N-isopropylacrylamide) (PNIPAAm), which exhibits a sharp lower critical solution temperature near 32 °C, alongside Pluronic/Poloxamer triblock copolymers and thermosensitive cellulose derivatives. Contemporary developments increasingly exploit biohybrid and nanocomposite strategies that incorporate natural polymers such as chitosan, gelatin, or hyaluronic acid with synthetic thermo-responsive segments, yielding materials with markedly enhanced mechanical robustness, biocompatibility, and physiologically relevant transition behavior. Cross-linking methodologies—encompassing covalent chemical approaches, dynamic physical interactions, and radiation-induced polymerization are rigorously assessed for their effects on network topology, swelling/deswelling kinetics, pore structure, and degradation characteristics. Prominent applications include on-demand drug and gene delivery, injectable in situ gelling systems, three-dimensional matrices for cell encapsulation and organoid culture, tissue engineering scaffolds, self-healing wound dressings, and responsive biosensing platforms. The integration of multi-stimuli orthogonality, nanotechnology, and artificial intelligence-guided materials discovery is anticipated to deliver fully programmable, patient-specific hydrogels, establishing them as pivotal enabling technologies in precision and regenerative medicine. Full article

Artificial muscles translate the biological principles of motion into soft, adaptive, and multifunctional actuation. This review accordingly highlights research into natural actuation strategies, such as skeletal muscles, muscular hydrostats, spider silk, and plant turgor systems, to reveal the principles underlying energy conversion and deformation control. Building on these insights, polymer-based artificial muscles based on these principles, including pneumatic muscles, dielectric elastomers, and ionic electroactive systems, are described and their capabilities for efficient contraction, bending, and twisting with tunable stiffness and responsiveness are summarized. Furthermore, the abilities of carbon nanotube composites and twisted yarns to amplify nanoscale dimensional changes through hierarchical helical architectures and achieve power and work densities comparable to those of natural muscle are discussed. Finally, the integration of these actuators into soft robotic systems is explored through biomimetic locomotion and manipulation systems ranging from jellyfish-inspired swimmers to octopus-like grippers, gecko-adhesive manipulators, and beetle-inspired flapping wings. Despite rapid progress in the development of artificial muscles, challenges remain in achieving long-term durability, energy efficiency, integrated sensing, and closed-loop control. Therefore, future research should focus on developing intelligent muscular systems that combine actuation, perception, and self-healing to advance progress toward realizing autonomous, lifelike machines that embody the organizational principles of living systems. Full article

Plastic pollution is a growing environmental and health issue due to the increasing presence of micro- and nanoplastics in terrestrial and aquatic ecosystems. Polystyrene nanoplastics (PS-NPs) are among the most extensively studied because of their wide occurrence, physicochemical stability, and availability for laboratory research. Their nanoscale size enables interaction with biological systems at the molecular level, promoting internalization, intracellular trafficking, and potential bioaccumulation. This review summarizes current knowledge on the cellular effects and molecular mechanisms of PS-NPs, particularly in human gastrointestinal models. The gastrointestinal tract is a primary route of nanoplastic exposure, where PS-NPs can cross epithelial barriers, interact with immune and epithelial cells, and disturb cellular homeostasis. Once internalized, PS-NPs can induce oxidative stress, mitochondrial dysfunction, and dysregulation of autophagy, leading to alterations in lipid and glucose metabolism. Excessive synthesis of reactive oxygen species may trigger DNA damage, activate the ATM/ATR–p53 signaling pathway, and impair DNA repair mechanisms, thereby contributing to genomic instability. Emerging evidence also shows that PS-NPs can interact with ion channels, affecting calcium homeostasis, membrane potential, and cell viability. Overall, these findings highlight the complex and multifaceted toxicity of PS-NPs at the cellular level and underscore the need for further research to assess the long-term risks of nanoplastic exposure. Full article

Luteolin is a naturally occurring flavonoid with growing interest for its senolytic properties. However, its poor water solubility and low bioavailability limit clinical application. This study aimed to develop and compare two types of nanocarriers, liposomes and polymeric nanoparticles, for the efficient delivery of luteolin in senolytic therapies. Liposomes with luteolin were prepared using the lipid film hydration method, followed by sonication and extrusion. Polymeric nanoparticles were developed via the nanoprecipitation method using pullulan acetate, a hydrophobic derivative obtained by chemical functionalization of pullulan. Pullulan was biosynthesized over 72 h using the microorganism Aureobasidium pullulans ICCF 36 (from CMII–INCDCF-ICCF). The formulation used a polymer-to-luteolin ratio of 10:1 (g/g) and Pluronic F127 as a stabilizer. Nanoprecipitation was carried out under controlled conditions: stirring at 700 rpm and dropwise addition at 0.5 mL/min. Luteolin was successfully encapsulated in both delivery systems. Liposomes showed an encapsulation efficiency of 85.07 ± 0.09% and nanoscale diameter. Polymeric nanoparticles demonstrated an encapsulation efficiency of 74.87 ± 0.05%, nanometric size and a formulation yield of 73.29 ± 0.09%. Both liposomal and polymeric nanoparticle systems effectively encapsulated luteolin, with high efficiency and yield. The formulations present promising potential for use in senolytic therapies, targeting age-related cellular dysfunction. Further studies will assess their release kinetics, biological activity, and senolytic effects in vitro and in vivo. Full article

The advancement of miniaturized liquid chromatography (M-LC) systems has drawn considerable attention for their ability to enhance sensitivity, expedite analysis, and minimize the environmental impact of chemical usage in various analytical processes. This review explores the fundamental principles and recent innovations in M-LC technology, including diverse pump designs, advanced column techniques, and the reduction in connection devices. Emphasizing the need for components that operate efficiently at the capillary or nanoscale with minimal dead volumes, we also discuss the development of benchtop instruments and mass spectrometry integrations. The review further highlights the growing applications of M-LC in food, environmental, and biological analyses, highlighting its potential as a powerful and emerging tool in separation science. Looking forward, addressing problems such as limited robustness, fabrication complexity, and integration with sensitive detectors will be instrumental to advancing M-LC technology. Modern innovation in microfabrication, materials science, and hyphenated methods holds great promise for allowing real-time, high-throughput, and portable analytical solutions in the near future. Full article

Composites of lyotropic liquid crystals with biocompatible luminescent nanoparticles represent multifunctional materials with high potential for application in molecular diagnostics and biomedicine. Their integration with microfluidics is a new and scarcely studied approach that offers unique opportunities for tuning properties of such nanomaterials and simulating the biological environment of their application. This paper analyzes the impact of the governing microfluidic factors, including wall effects and flow dynamics, on the intermolecular structure and optical properties of the mesogenic luminescent nanocomposite of tetraethylene glycol monododecyl ether and carbon dots. The nanoscale and microscale surface structure of microchannel walls was found to be the dominating factor for additional near-wall ordering of the intrinsic lamellar structure of the composite. A combination of controlled shear stress with heating–cooling cycles allowed for a gradual and reversible transformation of multilamellar vesicles into the axial lamellar structure, and provided the composite with anisotropic luminescence capabilities according to the study of the luminescent behavior of carbon dots. The collected experimental datasets, comprising hundreds of texture images, allowed for training the neural network for subsequent accurate recognition of the composite nanoscale organization and dynamic properties in straight and serpentine microchannels. The results will contribute to developing AI-powered microfluidic chips with integrated biocompatible nanocomposite materials for testing drug delivery systems and simulating biological capillary environment in organ-on-chip prototypes. Full article

This review is devoted to research in the field of photodynamic and photothermal therapies for malignant tumors. Special attention in the review is given to photosensitizers based on compounds with a tetrapyrrole ring system, their metal complexes, BODIPY and aza-BODIPY derivatives, squaraines, and photoactivators based on metal complexes with other ligands such as phenanthroline and its derivatives, metronidazole, pyridine, and imidazole derivatives. Additionally, the review considers nanosized carriers for photosensitizers, such as organic and inorganic nanoparticles, liposomes, and extracellular vesicles. This review also discusses the dark toxicity and phototoxicity of these compounds and the processes of free oxygen radical formation, mitochondrial dysfunction, and induction of apoptosis in cancer cells. It has been established that nanoscale delivery systems are more promising for use in photodynamic and photothermal therapy compared to molecular photosensitizers. This is due to their improved solubility in physiological environments, selective accumulation in tumors, prolonged photoactivity, and lower therapeutic dose, which allows for the minimization of the side effects of treatment. Among the molecular photosensitizers under consideration, amphiphilic tetrapyrroles appear to be the most promising. Specifically, tetrapyrrole complexes of indium (III) and iridium (III) with non-porphyrin ligands exhibit favorable photophysical and biological characteristics. The review also indicates that photosensitizers tend to localize in the mitochondria of tumor cells, contributing to oxidative stress and apoptosis activation. This review may be of interest to biochemists and oncologists. Full article

Background: Degenerative, metabolic and oncologic diseases are scarcely amenable to the complete reconstruction of tissue structure and functionalities using common therapeutic modalities. On the nanoscale, extracellular vesicles (EVs) and nanoparticles (NPs) have emerged as attractive candidates in regenerative and personalised medicine. However, EV transfection is hindered by its heterogeneity and low yield, while NPs suffer from cytotoxicity, immunogenicity, and long-term safety issues. Scope of Review: This review synthesises data from over 180 studies as part of a narrative synthesis, critically evaluating the disease-specific utility, mechanistic insights, and translational obstacles. The focus is laid on comparative cytotoxicity profiles, the capacities of hybrid EV–NP systems to circumvent mutual shortcomings, and the increasing impact of artificial intelligence (AI) on predictive modelling, as well as toxicity appraisal and manufacturing. Key Insights: EVs have inherent biocompatibility, immune evasive and organotropic signalling functions; NPs present structural flexibility, adjustable physicochemical properties, and industrial scalability. Common molecular pathways for NP toxicity, such as ROS production, MAPK and JAK/STAT activation, autophagy, and apoptosis, are significant biomarkers for regulatory platforms. Nanotechnological and biomimetic nanocarriers incorporate biological tropism with engineering control to enhance therapeutic efficacy, as well as their translational potential. AI approaches can support rational drug design, promote reproducibility across laboratories, and meet safe-by-design requirements. Conclusions: The intersection of EVs, NPs and AI signifies a turning point in regenerative nanomedicine. To advance this field, there is a need for convergence on experimental protocols, the adoption of mechanistic biomarkers, and regulatory alignment to ensure reproducibility and clinical competence. If realised, these endeavours will not only transition nanoscale medicament design from experimental constructs into reliable and patient-specific tools for clinical trials, but we also have the strong expectation that they could revolutionise future treatments of challenging human disorders. Full article

The nanoencapsulation of bioactive compounds such as β-carotene and microalgal extracts has emerged as an effective strategy to enhance their stability, bioavailability, and biological efficacy, particularly against oxidative stress. Dunaliella tertiolecta, a microalga rich in carotenoids and chlorophylls, presents notable antioxidant and erythroprotective properties; however, its bioactive potential is limited by low bioaccessibility and degradation during processing and digestion. This study aimed to develop and evaluate nanoliposomes loaded with D. tertiolecta extract and β-carotene as sustained-release systems to improve antioxidant performance and erythroprotective effects. The methodology involved optimizing microalgal cultivation under nitrogen and salinity stress to enhance pigment accumulation, followed by extraction, nanoencapsulation via the particle dispersion method, and physicochemical characterization of the nanoliposomes. Antioxidant capacity and release kinetics were assessed through ABTS and FRAP assays, while erythroprotective activity was evaluated by monitoring oxidative hemolysis in human erythrocytes. The release kinetics revealed an anomalous transport mechanism for both systems, with β-carotene showing faster and more efficient release due to its greater lipophilic compatibility with the nanoliposomal matrix. The nanoliposomal systems demonstrated nanoscale size, high encapsulation efficiency, sustained antioxidant release, and effective erythrocyte protection, with the extract-loaded formulation exhibiting synergistic effects superior to isolated β-carotene. These findings support the potential application of this nanotechnology-based delivery system in functional foods, nutraceuticals, and biomedical formulations aimed at preventing oxidative stress-related cellular damage. Full article

Extracellular vesicles are critical mediators of intercellular signaling. Recent studies have revealed that, in addition to vesicular structures, smaller non-vesicular nanoparticles—termed exomeres and supermeres—also participate in intercellular communication. Detailed characterization of these nanoscale entities within biological systems is essential for elucidating their structural and functional roles. Due to their sub-50 nm dimensions, high-resolution imaging modalities such as atomic force microscopy and electron microscopy are currently the primary techniques available for their visualization. In the present study, we employed low-voltage scanning electron microscopy to investigate the size of exomeres and supermeres isolated from human blood plasma via high-speed ultracentrifugation. Platelet-poor plasma was obtained from the blood of six healthy donors (two women and four men, aged 21–46 years). By ultracentrifugation (170,000× g for 4 h), the plasma was purified of extracellular vesicles. Two fractions were sequentially isolated: one containing exomeres (170,000× g for 20 h) and one containing supermeres (370,000× g for 20 h). The particles were examined using a Zeiss Auriga microscope with no sputter coating at an accelerating voltage of 0.4–0.5 kV. The images obtained from the fractions showed particles 10–50 nm in diameter, both individual particles and aggregated structures. The fractions were also slightly contaminated with larger particles, supposedly extracellular vesicles. Examining the fractions using a dynamic light scattering device additionally revealed the presence of particles 10–18 nm in size. It should be noted that the fractions obtained did indeed contain particles measuring 10–50 nm, which corresponds to the size of exomeres and supermeres. Low-voltage scanning electron microscopy allows for examination of the structure of exomeres and supermeres in blood plasma fractions. However, it should be noted that without the use of immunological identification, this method does not allow exomeres and supermeres to be distinguished from accompanying particles. It should also be noted that because the size of exomeres and supermeres is close to the detection threshold of low-voltage scanning electron microscopy, in such studies it is generally only possible to detect the size of these particles. Full article

Expansion microscopy (ExM) enables conventional light microscopes to achieve nanoscale resolution by physically enlarging biological specimens. While ExM has been widely applied in neurobiology, it has not been adapted for the enteric nervous system (ENS). Here, we provide a detailed and reproducible protocol for applying ExM to mouse colonic ENS tissue. The procedure includes preparation of the external muscle layers with the myenteric plexus, histochemical staining for NADPH-diaphorase, immunostaining for glial fibrillary acidic protein (GFAP), anchoring of biomolecules, gelation, proteinase K digestion, and isotropic expansion in a swellable polymer matrix. Step-by-step instructions, required reagents, and critical parameters are described to ensure robustness and reproducibility. Using this protocol, tissues expand 3–5-fold, allowing neuronal somata, fibers, and glial cell processes to be clearly visualized by standard brightfield or fluorescence microscopy. The tissue architecture is preserved, with distortion in the X–Y plane of about 7%. This protocol provides a reliable framework for high-resolution structural analysis of the ENS and can be readily adapted to other peripheral tissues. Full article

Traumatic injuries to the brain and spinal cord remain among the most challenging conditions in clinical neuroscience due to the complexity of repair mechanisms and the limited regenerative capacity of neural tissues. Nanotechnology has emerged as a transformative field, offering precise diagnostic tools, targeted therapeutic delivery systems, and advanced scaffolding platforms that are capable of overcoming the biological barriers to regeneration. This review summarizes the recent advances in nanoscale diagnostic markers, functionalized nanoparticles for drug delivery, and nanostructured scaffolds designed to modulate the injured microenvironment and support axonal regrowth and remyelination. Emerging evidence indicates that nanotechnology enables real-time, minimally invasive detection of inflammation, oxidative stress, and cellular damage, while improving therapeutic efficacy and reducing systemic side effects through targeted delivery. Electroconductive scaffolds and hybrid strategies that integrate electrical stimulation, gene therapy, and artificial intelligence further expand opportunities for personalized neuroregeneration. Despite these advances, significant challenges remain, including long-term safety, immune compatibility, the scalability of large-scale production, and translational barriers, such as small sample sizes, heterogeneous preclinical models, and limited follow-up in existing studies. Addressing these issues will be critical to realize the full potential of nanotechnology in traumatic brain and spinal cord injury and to accelerate the transition from promising preclinical findings to effective clinical therapies. Full article