Search Results (1,219)

Most nanoparticles and microparticles used as carriers of bioactive compounds are spherical in shape. Such particles are the easiest to obtain, as many processes spontaneously minimize the surface energy of the objects produced. However, in recent years, scientists have turned their attention to non-spherical particles in the hope of obtaining particles that interact with their environment in a tailored manner. The production of such particles should be easy and reproducible. The best candidates are spheroids produced by various methods. The most often used is the linear transformation of spheres during processes that preserve constant particle volume. The typical process consists of stretching a polymer matrix filled with spherical particles. The article delivers a critical overview of methods, discussing their advantages and disadvantages. A list of presented methods also includes the preparation of spheroids by polymer solution emulsification-solvent evaporation, controlled dispersion polymerization, electrohydrodynamic jetting, adsorption of amphiphilic copolymers on solid particles, and copolymer self-organization processes, as well as microfluidic methods, deformation of spherical particles into spheroids by irradiation, and phase microseparation. A special section is devoted to the self-organization of the particles at the phase boundaries. Eventually, the preparation and selected properties of two-dimensional and three-dimensional assemblies of spheroidal particles, particularly the preparation of a quasi-nematic colloidal crystal, are discussed. Full article

Studying nanoscale self-assembly in real time using external stimuli unlocks new opportunities for dynamic and adaptive materials. While electrostatic self-assembly is well-established, real-time monitoring of its structural evolution under light irradiation remains largely unexploited. In this study, we employ light-responsive azobenzene dyes (Acid Yellow 38, AY38) and pH-sensitive polyamidoamine (PAMAM) dendrimers to investigate the kinetics of electrostatic self-assembly under UV irradiation. Using a custom in situ small-angle neutron scattering (SANS) setup, we track the real-time morphological transformations of self-assembled structures with sub-minute resolution. We introduce two distinct pathways: method A (pre-irradiated cis-AY38 for controlled, slow kinetics) and method B (direct UV-induced self-assembly, fast kinetics). The results reveal that trans-cis isomerization kinetics dictate the rate of self-assembly, influencing aggregate stability, ζ-potential evolution, and final morphology. Structural analysis using dynamic and static light scattering (DLS and SLS) and SANS elucidates a transition from spherical to ellipsoidal morphologies governed by electrostatic and dipole-dipole interactions. These findings establish photoisomerization-driven self-assembly as a robust mechanism for tunable nanoscale architectures, paving the way for adaptive photonic materials, targeted drug delivery, and reconfigurable nanostructures. Full article

Antimicrobial peptides have been increasingly recognized as potential anticancer agents, with the KLA peptide (KLAKLAK₂) being one of the most well-known and successful examples. The research interest in the KLA peptide is attributed to its ability to induce apoptosis in cancer cells by disrupting the mitochondrial membrane. However, the KLA peptide exhibits poor cellular uptake and it lacks targeting specificity, limiting its clinical potential in cancer therapy. In this review, recent advances in nano-engineered delivery platforms for overcoming the limitations of KLA peptides and enhancing their anticancer efficacy are discussed. Specifically, various nanocarrier systems that enable targeted delivery, controlled release and/or improved bioavailability, including pH-responsive nanosystems, photo-chemo combination liposomes, self-assembled peptide-based nanostructures, nanogel-based delivery systems, homing domain-conjugated KLA structures, inorganic-based nanoparticles, and biomimetic nanocarriers, are highlighted. Additionally, synergistic strategies for combining KLA with chemotherapeutic agents or immunotherapeutic agents to overcome resistance mechanisms in cancer cells are examined. Finally, key challenges for the clinical application of these nanotechnologies are summarized and future directions are proposed. Full article

X-ray crystallography remains the gold standard for high-resolution structural biology, yet obtaining diffraction-quality crystals continues to pose a major bottleneck due to inherently low success rates. This review advocates a paradigm shift from probabilistic screening to rational engineering, reframing crystallization as a controllable self-assembly process. We provide a comprehensive overview of strategies that connect fundamental physicochemical principles to practical applications, beginning with contact design, which involves the active engineering of crystal contacts through surface entropy reduction (SER), introduction of electrostatic patches. Complementing these molecular approaches, we discuss physicochemical strategies that exploit heterogeneous nucleation on functionalized surfaces and gold nanoparticles (AuNPs) to lower the energy barrier for crystal formation. We also address scaffold design, utilizing rigid fusion partners and polymer-forming chaperones to promote crystallization even from low-concentration solutions. Furthermore, we highlight principles for controlling the behavior of multi-component complexes, based on our experimental experience. Finally, we examine de novo lattice design, which leverages AI tools such as AlphaFold and RFdiffusion to program crystal lattices from first principles. Together, these strategies establish an integrated workflow that links thermodynamic stability with crystallizability. Full article

This study reports the development of paclitaxel (PTX)-loaded human serum albumin (HSA) nanoparticles (NPs), surface-decorated with trastuzumab (TMAB), with potential applicability in HER2-oriented delivery. The NPs were obtained via thermally driven self-assembly followed by non-covalent antibody adsorption and they were characterized using Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and ζ-potential analysis. The drug association efficiency (%DAE), defined exclusively for PTX, was high for both HSA-PTX and HSA-PTX-TMAB NPs (96.4% and 98.2% w/w, respectively), with loading capacities (%LC) of 8.9% and 7.4%, respectively. TMAB decoration led to a modest increase in mean diameter and a reduction in surface charge, consistent with successful surface modification. Both formulations exhibited rapid early-phase PTX release followed by an apparent stabilization phase, with distinct kinetic behavior between HSA–PTX and HSA–PTX–TMAB NPs. Cytotoxicity in A549 cells after 18 h of exposure showed modest, non-differential effects consistent with controlled release and short-term assessment of non-specific toxicity. Overall, this thermally assembled albumin-based system provides a promising foundation for further evaluation of HER2-oriented PTX delivery. Full article

RNA interference (RNAi) holds promise as a gene-silencing therapy for liver cancer but faces challenges related to siRNA instability, short half-life, and inefficient cellular uptake. In this study, we designed a self-assembling RNA nanoparticle targeting three oncogenes—hTERT, BIRC5, and FGFR1—key drivers of cancer progression. These RNA nanoparticles demonstrated enhanced stability and specificity, eliminating the need for conventional toxic delivery carriers. Functional assays revealed that the nanoparticles effectively suppressed the proliferation, migration, tumor growth and apoptosis of a Hepatocellular carcinoma cell line, Hep3B. The nanoparticles exhibited excellent safety and efficacy in xenograft model mice, without off-target toxicity. This work introduces a scalable, biocompatible RNA nanoparticle platform with multi-targeting capability, paving the way for improved RNAi-based therapeutics. Our findings offer a promising strategy for advancing personalized cancer therapies and underscore the broader potential of RNA nanotechnology in addressing complex malignancies. Full article

This study investigates the electromagnetic field enhancement and optical response of self-assembled monolayer (SAM)-coated iron nanoparticles under laser excitation, with the aim of advancing optical gas sensing technologies. Using finite element method (FEM) simulations, we model the interaction of laser beams in both the visible (400–700 nm) and infrared (1000–2500 nm) spectral ranges with SAM-coated and uncoated nanoparticles. The results reveal that SAM coatings significantly amplify localized electromagnetic fields—reaching up to ~60 V/m in the visible range—while providing stable, wavelength-independent field distributions. In contrast, uncoated nanoparticles exhibit weaker but more variable field responses. Angular dependence analysis indicates maximal field enhancement at perpendicular (90°) detection, suggesting an orientation-sensitive design consideration for optical sensors. These findings demonstrate that SAM coatings enable stable, wavelength-independent electromagnetic responses, offering a promising pathway toward miniaturized and highly sensitive laser-based optical gas sensors. Full article

Utilization of natural processes can reduce the complexity and production cost of any device by limiting the necessary steps in the production scheme, especially when it comes to fibers with periodic changes in refractive index. One such process is the nematic–isotropic phase separation of liquid crystal-based composite confined in 1D space. In this paper, we analyze the behavior of polymer-stabilized liquid crystal-based self-assembled periodic structures in an external electric field. We performed a detailed analysis regarding the reorientation of liquid crystal molecules under two orthogonal directions of the external electric field applied to the examined sample. It was demonstrated that the period of the polymerized structure remains constant until full reorientation, as the electric field induces the formation of new periodic defects in LC orientation. Consequently, the structure’s effective birefringence changes quite drastically, and this observed change depends on the direction of the electric field vector. The obtained results seem promising when it comes to application of the proposed periodic structures as voltage or electric field sensors operating as long-period fiber gratings or fiber Bragg gratings for the visible or near-infrared spectral regions. Full article

Tea polyphenols (TPs) are promising natural bioactive compounds; however, their practical application is hindered by poor stability and low bioavailability. To address this challenge, we synthesized TP–iron nanoparticles (TP-Fe NPs) through coordination-driven self-assembly. Comprehensive characterization (SEM, TEM, FTIR, and XRD) confirmed the successful formation of stable TP-Fe NPs, primarily mediated by phenolic hydroxyl and carbonyl groups. Among TP-Fe NPs, the TP3-Fe1 NPs exhibited superior performance, achieving DPPH and ABTS radical scavenging rates of 65.71% and 89.64%, respectively, and inhibition rates of 91.44% against E. coli and 88.67% against S. aureus. Furthermore, TP3-Fe1 NPs demonstrated excellent biocompatibility, showing no significant cytotoxicity to L929 cells at 0.01–0.1 mg/mL. These findings highlight the potential of TP3-Fe1 NPs as a safe and effective material with dual functionality for antioxidant and antibacterial applications. Full article

We demonstrate that gold nanoparticles (AuNPs) are capable of unwinding double-stranded (ds) DNA. Upon unwinding, the exposed nucleobases of the separated strands adsorb onto the nanoparticle surface, resulting in the coating of the particles. The unwinding process was characterized by Atomic Force Microscopy (AFM) and absorption spectroscopy. Our results show that AuNPs initially bind to single-stranded overhangs at the duplex termini, forming dsDNA–nanoparticle dumbbells. This binding event subsequently initiates the separation of the DNA strands. As the unwinding proceeds, the nanoparticles become progressively wrapped by the unwound DNA strands, which leads to a gradual reduction in the interparticle distance within the dumbbells. This process is driven by the strong affinity of nucleobases for the gold surface. The efficiency of DNA unwinding was found to depend strongly on both nanoparticle size and temperature. These findings provide new insights into DNA-nanoparticle interactions and may facilitate the rational design of DNA–AuNP hybrid nanostructures such as dumbbell-shaped conjugates for applications in DNA-based nanoelectronics, biosensing, and self-assembled nanomaterials. Full article

Alterations in the expression of the Klotho gene have been associated with chronic kidney disease (CKD), and its potential as an early diagnostic biomarker is currently under active investigation. In this work, we report the development of a highly sensitive, label-free electrochemical DNA-based biosensor for the detection of a 100 mer DNA fragment corresponding to a partial region of Klotho mRNA. The proposed bioplatform integrates mixed self-assembled monolayers (SAMs) and gold nanoparticles for efficient DNA immobilization within a sandwich-type configuration, coupled with impedimetric detection. Different SAM architectures were evaluated by cyclic voltammetry and electrochemical impedance spectroscopy, with the binary monolayer composed of 1-hexadecanethiol (HDT) and the capture probe (CP) exhibiting the best analytical performance. The use of gold nanoparticle-modified screen-printed carbon electrodes (AuNPs–SPCEs) resulted in a 1.4-fold increase in the signal-to-noise ratio compared to screen-printed gold electrodes. Additionally, the incorporation of a blocking step using bovine serum albumin (BSA–HDT–CP–AuNPs–SPCE) enhanced the sensitivity by 1.6-fold compared to the unblocked system. The genosensor displayed a linear response in the concentration range of 3 × 10⁻¹⁰ to 7.5 × 10⁻⁸ M, achieving a detection limit of 0.09 nM. Relative standard deviations below 7.5% were obtained for different Klotho concentrations, confirming high intra-assay and intermediary precision. Selectivity assays demonstrated negligible signals for non-complementary sequences, while recovery experiments in spiked human serum samples yielded satisfactory values between 96.5% and 103.4%. Full article

Since the introduction of the DNA origami technology by Seeman and Rothemund, the integration of functional entities (nanoparticles, quantum dots, antibodies, etc.) has been of huge interest to broaden the area of applications for this technology. The possibility of precise functionalization of the DNA origami technology gives opportunity to build up complex novel structures, opening up endless opportunities in medicine, nanotechnology, photonics and many more. The main advantage of the DNA origami technology, namely the self-assembly mechanism, can represent a challenge in the construction of complex mixed-material structures. Commonly, DNA origami structures are purified post-assembly by filtration (either spin columns or membranes) to wash away excess staple strands. However, this purification step can be critical since these functionalized DNA origami structures tend to agglomerate during purification. Therefore, custom production and purification procedures need to be applied to produce purified functionalized DNA origami structures. In this paper, we present a workflow to produce functionalized DNA origami structures, as well as a method to qualify the successful hybridization of a quantum dot to a square frame DNA origami structure. Through the utilization of a FRET fluorophore–quencher pair as well as a subsequent assembly, successful hybridization can be performed and confirmed using photoluminescence measurements. Full article

Background/Objectives: A carrier-free self-assembled nanomedicine delivery system refers to a high drug-loading nanomedicine delivery system prepared by one or more active drug ingredients through supramolecular self-assembly, which has the advantages of high drug-loading and a simple preparation process, enabling multidrug synergistic therapy. 10-hydroxycamptothecin (HCPT) have active antitumor effects. Pentacyclic triterpenes are natural active components with a wide range of pharmacological activities. This study aimed to investigate the impact of structural types on the self-assembly of pentacyclic triterpenes and HCPT. Methods: Molecular docking studies were performed. Self-assembled nanoparticles were designed by co-assembling ursolic acid (UA), asiatic acid (AA), oleanic acid (OA), and betulinic acid (BA) with HCPT via anti-solvent precipitation combined with ultrasonication, followed by characterization. Cytotoxicity assays using the CCK-8 method revealed that the prepared self-assembled nanoparticles exhibited concentration-dependent inhibitory effects against A375, AGS, HCT-116, and HepG2 tumor cells. Confocal laser scanning microscopy (CLSM) indicated that UA/HCPT nanoparticles (UA/HCPT-NPs) were more efficiently internalized and accumulated in cells compared with the UA + HCPT physical mixture. Results: Both in vitro and in vivo results demonstrated that the self-assembled nanoparticles significantly enhanced antitumor efficacy while exerting minimal toxicity on major organs within the tested dose range. Conclusions: In summary, these findings highlight that pentacyclic triterpenoids components possess significant self-assembly potential, and that dual-drug co-delivery via self-assembled nanoparticles represents as a promising strategy for cancer therapy. Full article

This work develops a novel Ni-Co nanoparticles coupled with Ni₃S₂ and Co₉S₈ phases on nickel foam (denoted as Ni-Co NPS@Ni₃S₂/Co₉S₈/NF) hybrid structure material as a bifunctional water electrolysis catalyst. The self-assembly Ni-Co alloy phases enhance electrical conductivity, while the synergistic interactions among the three components (Ni-Co, Ni₃S₂ and Co₉S₈) optimize the lattice parameters and electronic environment for boosting both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The catalyst achieves low overpotentials of 106 mV for HER and 185 mV for OER at 10 mA·cm⁻² in 1M KOH, along with a very low charge-transfer resistance. Density functional theory (DFT) calculations reveal that the multi-component interaction narrows the band gap and optimizes the hydrogen adsorption free energy (ΔG_H*) as well as the adsorption free energies of OER intermediates (ΔG_OH*). This work identifies the hybrid structure as the key to the enhanced activity and offers a promising strategy for designing efficient nickel–cobalt-based electrocatalysts. Full article

Background: Paclitaxel (PTX), a taxane chemotherapy drug, is widely regarded as one of the most potent and clinically effective treatments for advanced and resistant cancers. However, paclitaxel’s poor bioavailability is attributed to its unfavorable physicochemical properties, including low solubility and permeability. Nanosizing and multidrug combination strategies have emerged as key approaches to enhance the formulation of such compounds. Pterostilbene (PTE), a polyphenolic compound, possesses extensive anti-cancer properties and favorable hydrogen bond formation sites. In this study, PTE was employed to co-assemble with PTX to improve its physicochemical properties and enhance therapeutic efficacy. Methods: Paclitaxel-pterostilbene nanoparticles (PTX-PTE NPs) were characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Results: PTX-PTE nanoparticles significantly improved the water solubility (7fold increase) and cytotoxicity of paclitaxel in tumor cells. The enhanced antitumor efficacy was achieved through P-gp and CDK1 protein downregulation, increased drug accumulation, and cell cycle inhibition. Conclusions: These improvements are attributed to the nanoparticles’ amorphous structure and nanoscale properties. In addition, the combined use of PTX and PTE significantly enhanced the cytotoxicity against human non-small cell lung cancer A549 cells. PTX-PTE nanoparticles show promise for improving drug delivery and overcoming multidrug resistance in A549 cells. Full article