Search Results (57)

Cancer immunotherapy increasingly relies on nucleic acid-based vaccines, yet achieving efficient and safe delivery remains a critical limitation. Polyplexes—electrostatic complexes of cationic polymers and nucleic acids—have emerged as versatile carriers offering greater chemical tunability and multivalent targeting capacity compared to lipid nanoparticles, with lower immunogenicity than viral vectors. This review summarizes key design principles governing polyplex performance, including polymer chemistry, architecture, and assembly route—emphasizing microfluidic fabrication for improved size control and reproducibility. Mechanistically, effective systems support stepwise delivery: tumor targeting, cellular uptake, endosomal escape (via proton-sponge, membrane fusion, or photochemical disruption), and compartment-specific cargo release. We discuss therapeutic applications spanning plasmid DNA, siRNA, miRNA, mRNA, and CRISPR-based editing, highlighting preclinical data across multiple tumor types and early clinical evidence of on-target knockdown in human cancers. Particular attention is given to physiological barriers and engineering strategies—including size-switching systems, charge-reversal polymers, and tumor-penetrating peptides—that improve intratumoral distribution. However, significant challenges persist, including cationic toxicity, protein corona formation, manufacturing variability, and limited clinical responses to date. Current evidence supports polyplexes as a modular platform complementary to lipid nanoparticles in selected oncology indications, though realizing this potential requires continued optimization alongside rigorous translational development. Full article

L-asparaginase (L-ASNase) is a vital enzymatic drug widely used for treating acute lymphoblastic leukemia (ALL) and certain lymphomas. However, its clinical application is often limited by a short plasma half-life, pronounced immunogenicity, and systemic toxicities. To address these challenges, we recently developed conjugates of L-ASNase with cationic polymers, enhancing its cytostatic activity by increasing enzyme binding with cancer cells. The present study focuses on the development of liposomal formulations of E. coli L-asparaginase (EcA) and its conjugates with cationic polymers: the natural oligoamine spermine (spm) and a synthetic polyethylenimine–polyethyleneglycol (PEI-PEG) copolymer. This approach aims to improve enzyme encapsulation efficiency and stability within liposomes. Various formulations—including EcA conjugates with polycations incorporated into 100 nm and 400 nm phosphatidylcholine/cardiolipin (PC/CL, 80/20) anionic liposomes—were synthesized as a delivery system of high enzyme load. Fourier Transform Infrared (FTIR) spectroscopy confirmed successful enzyme association with liposomal carriers by identifying characteristic changes in the vibrational bands corresponding to both protein and lipid components. In vitro release studies demonstrated that encapsulating EcA formulations in liposomes more than doubled their half-release time (T_1/2), depending on the formulation. Cytotoxicity assays against Raji lymphoma cells revealed that liposomal formulations, particularly 100 nm EcA-spm liposomes, exhibited markedly superior anti-proliferative activity, reducing cell viability to 4.5%, compared to 35% for free EcA. Confocal Laser Scanning Microscopy (CLSM) provided clear visual and quantitative evidence that enhanced cellular internalization of the enzyme correlates directly with its cytostatic efficacy. Notably, formulations showing higher intracellular uptake produced greater cytotoxic effects, emphasizing that hydrolysis of asparagine inside cancer cells, rather than extracellularly, is critical for therapeutic success. Among all tested formulations, the EcA-spermine liposomal conjugate demonstrated the highest fluorescence intensity within cells providing enhanced cytotoxicity. These results strongly indicate that encapsulating cationically modified L-ASNase in liposomes is a highly promising strategy to improve targeted cellular delivery and prolonged enzymatic activity. This strategy holds significant potential for developing more effective and safer antileukemic therapies. Full article

Hearing loss is a major health burden, often caused by ototoxic drugs such as cisplatin and gentamicin. Effective therapy is limited by the poor penetrability of drugs into inner ear compartments. This study aimed to develop and test magnetic cationic liposomes as nanocarriers for targeted corticosteroid delivery to auditory hair cells. Carboxymethyl chitosan–coated liposomes were prepared by the lipid film hydration method, incorporating magnetic nanoparticles and dexamethasone phosphate in their aqueous core. The optimal liposomal formulation, in terms of size, zeta potential, and drug leakage over time, was selected and tested in an in vitro model of drug-induced ototoxicity. HEI-OC1 cells exposed to cisplatin or gentamicin were co-treated with the liposomal formulations, and viability, mitochondrial membrane potential, and β-galactosidase activity were assessed. The results demonstrated that magnetic, polymer-coated liposomes protected against cytotoxicity by preserving mitochondrial function and significantly reducing senescence. These findings provide a proof of concept for magnetically responsive liposomal systems as potential therapeutic platforms for preventing or treating drug-associated hearing loss. Full article

Background: RNA interference (RNAi) is a powerful tool that can target many proteins without the expensive and time-consuming drug development studies. However, due to the challenges in delivering RNA molecules, the potential impact of RNAi approaches is yet to be fully realized in clinical settings. Lipid nanoparticles (LNPs) have been the most successful delivery system for nucleic acids, but targeted delivery to a solid tumor still eludes the developed LNPs. We hypothesized that specially designed low-molecular-weight PEIs can partially or completely replace the ionizable lipids for more accommodating vehicles due to the structural flexibility offered by polymers, which could lead to safer and more efficient nucleic acid delivery. Methods: To achieve this, we first optimized the LNP formulations as a point of reference for three outcomes: cellular uptake, cytotoxicity, and silencing efficiency. Using a response surface methodology (Design Expert), we optimized siRNA delivery by varying mole fractions of lipid components. Leveraging the optimal LNP formulation, we integrated specifically designed cationic polymers as partial or complete replacements for the ionizable lipid. This methodological approach, incorporating optimal combined designs and response surface methodologies, refined the LPNPs to an optimal efficiency. Results: Our data revealed that DOPE and Dlin-MC3-DMA contributed to higher efficiency in selected breast cancer cells over DSPC and ALC-0315 as neutral and ionizable lipids, respectively, based on the software analysis and direct comparative experiments. Incorporation of selected polymers enhanced the cellular internalization significantly, which in some formulations resulted in higher efficiency. Conclusions: These findings offer a framework for the rational design of LPNPs, that could enhance the passive targeting and silencing efficiency in cancer treatment and broader applications for RNAi-based strategies. Full article

Background Despite many studies on polymer-incorporated nanocarriers for ophthalmic drug delivery, few have thoroughly explored the relationship between coating composition and performance. This study aimed to evaluate the effects of three commonly used cationic polymers—distearoyl phosphatidylethanolamine-polyethylene glycol 1000-poly(amidoamine) (DSPE-PEG1000-PAMAM), trimethyl chitosan (TMC), and (2,3-dioleoyloxypropyl) trimethylammonium chloride (DOTAP)—on the corneal behaviors and anti-cataract efficacy of diosmetin (DIO)-loaded micelles (D-M-P, D-M-T, and D-M-D, respectively). Methods The DIO-loaded micelles were prepared using the thin-film dispersion method and incorporated with the three polymers through hydrophobic interactions and electrostatic adsorption. Structural characterization was demonstrated by TEM imaging and particle size analyzer. In vitro release behavior was detected by the dialysis method. Cell viability of D-M-P, D-M-T, and D-M-D on L929 cells was detected by CCK-8 assays, with cellular uptake performed using coumarin 6 as the fluorescence indicator. Precorneal retention behaviors of these three vesicles were observed by In Vivo Imaging System. Transcorneal permeability was determined by modified Franz diffusion method and the permeation routes of the vesicles are investigated. Selenite-induced cataract model was established. The anti-cataract effects of three different DIO-loaded micelles were evaluated by the observation of lens opacity and antioxidant enzyme activities. Eye Irritation of the DIO in different preparations was estimated using the Draize test, along with H&E staining of the corneas. Results Structural characterization of DIO-loaded micelles revealed that the vesicles were spherical, with a uniform size distribution of around 28 nm, a similar surface potential of approximately 6.0 mV, and a high DIO entrapment efficiency of about 95%. Compared to the DIO suspension, all three formulations exhibited a significant sustained-release effect. They showed no signs of irritation and demonstrated increased IC50 values in L929 cells, indicating improved biocompatibility. Cellular uptake in human lens epithelial cells (HLECs) was assessed using confocal laser scanning microscopy. C-M-T displayed the highest fluorescence signals, with a cellular internalization 3.2 times greater than that of the solution group. Both C-M-T and C-M-P enhanced vesicle retention on the corneal surface by at least 47.8% compared to the Cou-6 solution. Furthermore, TMC facilitated the paracellular transport of vesicles into the deepest layers of the cornea and delivered DIO across the cornea, with a P_app value 3.11 times and 1.49 times those of D-M-D and D-M-P, respectively. In terms of therapeutic efficacy, D-M-T demonstrated the most significant attenuation of lens opacity, along with enhanced antioxidant enzyme activities and inhibition of lipid peroxidation. Conclusion The modification of micelle vesicles with different cationic polymers significantly influences their performance in ocular drug delivery. Among the tested formulations, D-M-T stands out due to its multiple advantages, including enhanced transcorneal drug delivery, therapeutic efficacy for DIO, and safety, making it the most promising candidate for ophthalmic applications. Full article

Background/Objectives: The endosomal escape of lipid nanoparticles (LNPs) is crucial for efficient mRNA-based therapeutics. Here, we present a cationic polymeric micelle (cPM) as a safe and potent co-delivery system with enhanced endosomal escape capabilities. Methods: We synthesized a cationic and ampholytic di-block copolymer, poly (poly (ethylene glycol)_4-5 methacrylate_a-co-hexyl methacrylate_b)_X-b-poly(butyl methacrylate_c-co-dimethylaminoethyl methacrylate_d-co-propyl acrylate_e)_Y (p(PEG_4-5MA_a-co-HMA_b)_X-b-p(BMA_c-co-DMAEMA_d-co-PAA_e)_Y), via reversible addition–fragmentation chain transfer polymerization. The cPMs were then formulated using the synthesized polymer by the dispersion–diffusion method and characterized by dynamic light scattering (DLS) and cryo-transmission electron microscopy (CryoTEM). The membrane-destabilization activity of the cPMs was evaluated by a hemolysis assay. We performed an in vivo functional assay of firefly luciferase (Fluc) mRNA using two of the most commonly studied LNPs, SM102 LNP and Dlin-MC3-DMA LNPs. Results: With a particle size of 61.31 ± 0.68 nm and a zeta potential of 37.76 ± 2.18 mV, the cPMs exhibited a 2–3 times higher firefly luciferase signal at the injection site compared to the control groups without cPMs following intramuscular injection in mice, indicating the high potential of cPMs to enhance the endosomal escape efficiency of mRNA-LNPs. Conclusions: The developed cPM, with enhanced endosomal escape capabilities, presents a promising strategy to improve the expression efficiency of delivered mRNAs. This approach offers a novel alternative strategy with no modifications to the inherent properties of mRNA-LNPs, preventing any unforeseeable changes in formulation characteristics. Consequently, this polymer-based nanomaterial holds immense potential for clinical applications in mRNA-based vaccines. Full article

Currently, lipid/polymer membranes are used in taste sensors to quantify food taste. This research aims to improve sweetness sensors by more selectively detecting uncharged sweetening substances, which have difficulty obtaining a potentiometric response. Lipid/polymer membranes with varying amounts of tetradodecylammonium bromide (TDAB) and 1,2,4-benzene tricarboxylic acid (trimellitic acid) were prepared. The carboxyl groups of trimellitic acid bind metal cations, and the sweetness intensity is estimated by measuring the potential change, as a sensor response, when these cations are complexed with sugars. This research showed that the potential of a sensor using the membrane with enough trimellitic acid in a sucrose solution remained constant, regardless of TDAB amounts, but the potential in the tasteless, so-called reference solution, depended on TDAB. By optimizing the content of TDAB and trimellitic acid, a sensor response of −100 mV was achieved, which is over 20% more sensitive than a previous sensor. This sensor also demonstrated increased selectivity to sweetness, with similar interference from other tastes (saltiness, sourness, umami, and bitterness) compared to previous sensors. As a result, the sensitivity to sweetness was successfully improved. This result contributes to the development of novel sensors, further reducing the burden on humans in quality control and product development. Full article

Cationic vaccines of nanometric sizes can directly perform the delivery of antigen(s) and immunomodulator(s) to dendritic cells in the lymph nodes. The positively charged nanovaccines are taken up by antigen-presenting cells (APCs) of the lymphatic system often originating the cellular immunological defense required to fight intracellular microbial infections and the proliferation of cancers. Cationic molecules imparting the positive charges to nanovaccines exhibit a dose-dependent toxicity which needs to be systematically addressed. Against the coronavirus, mRNA cationic nanovaccines evolved rapidly. Nowadays cationic nanovaccines have been formulated against several infections with the advantage of cationic compounds granting protection of nucleic acids in vivo against biodegradation by nucleases. Up to the threshold concentration of cationic molecules for nanovaccine delivery, cationic nanovaccines perform well eliciting the desired Th 1 improved immune response in the absence of cytotoxicity. A second strategy in the literature involves dilution of cationic components in biocompatible polymeric matrixes. Polymeric nanoparticles incorporating cationic molecules at reduced concentrations for the cationic component often result in an absence of toxic effects. The progress in vaccinology against cancer involves in situ designs for cationic nanovaccines. The lysis of transformed cancer cells releases several tumoral antigens, which in the presence of cationic nanoadjuvants can be systemically presented for the prevention of metastatic cancer. In addition, these local cationic nanovaccines allow immunotherapeutic tumor treatment. Full article

Background/Objectives: The development of polymer–lipid hybrid nanoparticles (PLNs) is a promising area of research, as it can help increase the stability of cationic lipid carriers. Hybrid PLNs are core–shell nanoparticle structures that combine the advantages of both polymer nanoparticles and liposomes, especially in terms of their physical stability and biocompatibility. Natural polymers such as polyhydroxyalkanoate (PHA) can be used as a matrix for the PLNs’ preparation. Methods: In this study, we first obtained stable cationic hybrid PLNs using a cationic liposome (CL) composed of a polycationic lipid 2X3 (1,26-bis(cholest-5-en-3β-yloxycarbonylamino)-7,11,16,20-tetraazahexacosane tetrahydrochloride), helper lipid DOPE (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine), and the hydrophobic polymer mcl-PHA, which was produced by the soil bacterium Pseudomonas helmantisensis P1. Results: The new polymer-lipid carriers effectively encapsulated and delivered model mRNA-eGFP (enhanced green fluorescent protein mRNA) to BHK-21 cells. We then evaluated the role of mcl-PHA in increasing the stability of cationic PLNs in ionic solutions using dynamic light scattering data, electrophoretic mobility, and transmission electron microscopy techniques. Conclusions: The results showed that increasing the concentration of PBS (phosphate buffered saline) led to a decrease in the stability of the CLs. At high concentrations of PBS, the CLs aggregate. In contrast, the presence of isotonic PBS did not result in the aggregation of PLNs, and the particles remained stable for 120 h when stored at +4 °C. The obtained results show that PLNs hold promise for further in vivo studies on nucleic acid delivery. Full article

We propose a nucleic acids dilution-induced assembly (NADIA) method for the preparation of lipid nanoparticles. In the conventional method, water-soluble polymers such as nucleic acids and proteins are mixed in the aqueous phase. In contrast, the NADIA method, in which self-assembly is triggered upon dilution, requires dispersion in an alcohol phase without precipitation. We then investigated several alcohols and discovered that propylene glycol combined with sodium chloride enabled the dispersion of plasmid DNA and protamine sulfate in the alcohol phase. The streamlined characteristics of the NADIA method enable the preparation of extracellular vesicles-mimicking lipid nanoparticles (ELNPs). Among the mixing methods using a micropipette, a syringe pump, and a microfluidic device, the lattermost was the best for decreasing batch-to-batch differences in size, polydispersity index, and transfection efficiency in HepG2 cells. Although ELNPs possessed negative ζ-potentials and did not have surface antigens, their transfection efficiency was comparable to that of cationic lipoplexes. We observed that lipid raft-mediated endocytosis and macropinocytosis contributed to the transfection of ELNPs. Our strategy may overcome the hurdles linked to supply and quality owing to the low abundance and heterogeneity in cell-based extracellular vesicles production, making it a reliable and scalable method for the pharmaceutical manufacture of such complex formulations. Full article

Synthetic polymer surfaces provide an excellent opportunity for developing materials with inherent antimicrobial and/or biocidal activity, therefore representing an answer to the increasing demand for antimicrobial active medical devices. So far, biologists and material scientists have identified a few features of bacterial cells that can be strategically exploited to make polymers inherently antimicrobial. One of these is represented by the introduction of cationic charges that act by killing or deactivating bacteria by interaction with the negatively charged parts of their cell envelope (lipopolysaccharides, peptidoglycan, and membrane lipids). Among the possible cationic functionalities, the antimicrobial activity of polymers with quaternary ammonium centers (QACs) has been widely used for both soluble macromolecules and non-soluble materials. Unfortunately, most information is still unknown on the biological mechanism of action of QACs, a fundamental requirement for designing polymers with higher antimicrobial efficiency and possibly very low toxicity. This mini-review focuses on surfaces based on synthetic polymers with inherently antimicrobial activity due to QACs. It will discuss their synthesis, their antimicrobial activity, and studies carried out so far on their mechanism of action. Full article

Ferroptosis has garnered attention as a potential approach to fight against cancer, which is characterized by the iron-driven buildup of lipid peroxidation. However, the robust defense mechanisms against intracellular ferroptosis pose significant challenges to its effective induction. In this paper, an effective gene delivery vehicle was developed to transport solute carrier family 7 member 11 (SLC7A11) shRNA (shSLC7A11), which downregulates the expression of the channel protein SLC7A11 and glutathione peroxidase 4 (GPX4), evoking a surge in reactive oxygen species production, iron accumulation, and lipid peroxidation in hepatocellular carcinoma (HCC) cells, and subsequently leading to ferroptosis. This delivery system is composed of an HCC-targeting lipid layer and esterase-responsive cationic polymer, a poly{N-[2-(acryloyloxy)ethyl]-N-[p-acetyloxyphenyl]-N} (PQDEA) condensed shSLC7A11 core (G−LPQDEA/shSLC7A11). After intravenous (i.v.) injection, G−LPQDEA/shSLC7A11 quickly accumulated in the tumor, retarding its growth by 77% and improving survival by two times. This study is the first to construct a gene delivery system, G−LPQDEA/shSLC7A11, that effectively inhibits HCC progression by downregulating SLC7A11 expression. This underscores its therapeutic potential as a safe and valuable candidate for clinical treatment. Full article

Single-stranded messenger ribonucleic acid (mRNA) plays a pivotal role in transferring genetic information, and tremendous effort has been devoted over the years to utilize its transcription efficacy in therapeutic interventions for a variety of diseases with high morbidity and mortality. Lipid nanocarriers have been extensively investigated for mRNA delivery and enabled the rapid and successful development of mRNA vaccines against SARS-CoV-2. Some constraints of lipid nanocarriers have encouraged the development of alternative delivery systems, such as polymer-based soft nanoparticles, which offer a modular gene delivery platform. Such macromolecule-based nanocarriers can be synthetically articulated for tailored parameters including mRNA protection, loading efficacy, and targeted release. In this review, we highlight recent advances in the development of polymeric architectures for mRNA delivery, their limitations, and the challenges that still exist, with the aim of expediting further research and the clinical translation of such formulations. Full article

Gene therapy is extensively studied as a realistic and promising therapeutic approach for treating inherited and acquired diseases by repairing defective genes through introducing (transfection) the “healthy” genetic material in the diseased cells. To succeed, the proper DNA or RNA fragments need efficient vectors, and viruses are endowed with excellent transfection efficiency and have been extensively exploited. Due to several drawbacks related to their use, nonviral cationic materials, including lipidic, polymeric, and dendrimer vectors capable of electrostatically interacting with anionic phosphate groups of genetic material, represent appealing alternative options to viral carriers. Particularly, dendrimers are highly branched, nanosized synthetic polymers characterized by a globular structure, low polydispersity index, presence of internal cavities, and a large number of peripheral functional groups exploitable to bind cationic moieties. Dendrimers are successful in several biomedical applications and are currently extensively studied for nonviral gene delivery. Among dendrimers, those derived by 2,2-bis(hydroxymethyl)propanoic acid (b-HMPA), having, unlike PAMAMs, a neutral polyester-based scaffold, could be particularly good-looking due to their degradability in vivo. Here, an overview of gene therapy, its objectives and challenges, and the main cationic materials studied for transporting and delivering genetic materials have been reported. Subsequently, due to their high potential for application in vivo, we have focused on the biodegradable dendrimer scaffolds, telling the history of the birth and development of b-HMPA-derived dendrimers. Finally, thanks to a personal experience in the synthesis of b-HMPA-based dendrimers, our contribution to this field has been described. In particular, we have enriched this work by reporting about the b-HMPA-based derivatives peripherally functionalized with amino acids prepared by us in recent years, thus rendering this paper original and different from the existing reviews. Full article

The growing significance of messenger RNA (mRNA) therapeutics in diverse medical applications, such as cancer, infectious diseases, and genetic disorders, highlighted the need for efficient and safe delivery systems. Lipid nanoparticles (LNPs) have shown great promise for mRNA delivery, but challenges such as toxicity and immunogenicity still remain to be addressed. In this study, we aimed to compare the performance of polyplex nanomicelles, our original cationic polymer-based carrier, and LNPs in various aspects, including delivery efficiency, organ toxicity, muscle damage, immune reaction, and pain. Our results showed that nanomicelles (PEG-PAsp(DET)) and LNPs (SM-102) exhibited distinct characteristics, with the former demonstrating relatively sustained protein production and reduced inflammation, making them suitable for therapeutic purposes. On the other hand, LNPs displayed desirable properties for vaccines, such as rapid mRNA expression and potent immune response. Taken together, these results suggest the different potentials of nanomicelles and LNPs, supporting further optimization of mRNA delivery systems tailored for specific purposes. Full article