Search Results (113)

Liposomes started to be studied for drug delivery in 1970s, taking advantage of their ability to encapsulate hydrophilic and hydrophobic drugs using biodegradable and biocompatible molecules. Nowadays, they remain one of the most promising strategies for drug delivery not only in cancer treatment but also in gene therapies and vaccines. The design and development of liposomal systems have evolved significantly over the past decades, moving from conventional formulations to advanced, stimulus-responsive, and multifunctional nanocarriers. Analogous to the myth of the Trojan Horse, liposomes must mislead the host immune system to reach the interior of cancer cells in order to deliver the therapeutic payload. There are many barriers that liposomes have to overcome to circulate through the bloodstream and specifically target cancer cells without damaging other tissues. Crucial parameters such as lipid composition, particle size, zeta potential, and PEGylation have been systematically optimized to enhance pharmacokinetics and biodistribution and to improve delivery efficiency. Furthermore, conjugation with antibodies, peptides, or small molecules has enabled active targeting, while stimuli such as pH, temperature, and enzymatic activity have been exploited for controlled drug release within the tumor microenvironment. Such innovations have laid the groundwork for translating liposomal formulations from the bench to clinical applications. In this paper, we evaluate the physicochemical features of liposomal design that underpin their suitability and efficacy for anticancer drug delivery. We aimed to focus on two main aspects: conducting an exhaustive review of the physicochemical parameters of liposomal drugs that have already been approved by regulatory agencies, while maintaining a pedagogical approach when explaining the key design parameters for the optimal design of liposomes in oncology in detail. Full article

The challenges associated with solubility and bioavailability of porphyrinoid-type photosensitizers in photodynamic therapy require solutions that are based on modern drug carriers, including polymeric nanoparticles. With that in mind this review discusses poly(lactic-co-glycolic acid, PLGA)-based polymeric nanoparticles encapsulating selected well-known photosensitizers, such as protoporphyrin IX, tetrahydroxyphenylporphyrin, chlorin e6, and tetracarboxyphenylporphyrin, with a view to the physicochemical and biological properties. Also discussed are their potential medical applications towards photodynamic and sonodynamic therapy. PLGA-based nanoparticles, encapsulating photosensitizers, were analysed in terms of particle size, surface charge, morphology, loading efficiency, release kinetics, and stability. Moreover, the cellular uptake and subcellular localisation of carriers were considered in correlation to polymer composition and surface functionalisation. Special attention was given to how PEGylation, lipid-hybrid coatings, or the incorporation of additional therapeutic or imaging agents has modulated both the physicochemical properties and biological activities of photosensitizers. The comparative assessment of different porphyrinoid-based photosensitizers highlighted how hydrophobicity, amphiphilicity, and molecular structure have an influence on encapsulation efficiency and therapeutic outcomes. Furthermore, issues such as the premature release of photosensitizers, along with limited bioavailability, and limited penetration through biological barriers were addressed as well as some proposed mitigation strategies. Overall, this review highlights the versatility of PLGA nanoparticles as a powerful platform for photosensitizer delivery, with promising implications for advancing polymer-based nanomedicine and improving the efficacy of photodynamic therapy. Full article

Nanogels provide unique opportunities for stabilizing fragile enzymes through soft, hydrated polymer networks. Here, we report the development of a glutathione peroxidase (GPx)-loaded nanogel (GPxNG) engineered via a mild “grafting-to” epoxy–amine coupling strategy to enhance enzyme stability and antioxidant function. An amphiphilic copolymer composed of methacrylated 2,2,6,6-tetramethyl-4-piperidyl (PMA) and glycidyl methacrylate (GMA) was synthesized by controlled reversible addition–fragmentation chain-transfer (RAFT) polymerization using a poly(ethylene glycol) (PEG) macro-chain transfer agent (macro-CTA), yielding well-defined polymer chains with reactive epoxy groups. Covalent conjugation between polymer epoxides and GPx enzyme surface amines generated soft, PEGylated nanogels with high coupling efficiency, uniform particle sizes, and excellent colloidal stability. The engineered nanogels exhibited shear-thinning injectability, robust storage stability, and non-cytotoxic behavior in RAW 264.7 macrophages. Compared with native GPx enzyme, GPxNGs demonstrated significantly enhanced reactive oxygen species (ROS) scavenging activity, including strong inhibition of lipid peroxidation and copper-induced low-density lipoprotein (LDL) oxidation. Importantly, the nanogels preserved GPx enzyme activity after extended storage, freeze–thaw cycles, and repeated catalytic use, whereas the free enzyme rapidly lost function. This protective effect arises from the nanoscale confinement of the GPx enzyme within the flexible PEG-based network, which limits unfolding and aggregation. Overall, this work introduces a simple and biocompatible “grafting-to” nanogel platform capable of stabilizing redox-active enzymes without harsh conditions. The GPx nanogels combine high enzymatic preservation, potent antioxidant activity, and excellent handling properties, highlighting their potential as a therapeutic nanoplatform for mitigating oxidative stress-associated disorders such as atherosclerosis. Full article

For complexation of mRNA into polyplexes, double-pH-responsive lipo-xenopeptides (XP), comprising tetraethylene pentamino succinic acid (Stp) and lipoamino fatty acids (LAFs), were combined with PEGylated lipids, either DMG-PEG 2 kDa (DMG-PEG) or azido-group-containing DSPE-PEG 2 kDa (DSPE-PEG-N3), to increase colloidal stability and to facilitate ligand-mediated targeted mRNA delivery. LAF-XPs mixed with DMG-PEG at low (1.5% and 3%) molar ratios improved colloidal stability and retained transfection efficiency. PEGylation also enabled the formulation of otherwise unstable carrier complexes and prevented aggregation induced by salt, proteins, and serum. PEGylation of more positively charged Stp-LAF₂ mRNA polyplexes decreased fibrinogen adsorption. More neutral, LAF-rich Stp-LAF₄ polyplexes exhibited low fibrinogen binding without PEGylation. Intravenous administration of these stabilized mRNA complexes demonstrated enhanced biosafety while preserving transfection efficiency. DSPE-PEG-N3 was selected for cell targeting after strain-promoted azide-alkyne cycloaddition (SPAAC)-mediated click-coupling of DBCO-modified ligands. Higher PEG ratios (10% and 20%) provided effective shielding but reduced transfection efficiency, a drawback known as the “PEG dilemma”. Functionalization with an EGFR-targeting ligand restored transfection in EGFR-positive cell lines in a ligand-specific manner. High transfection efficiency is consistent with a lipophilic-to-hydrophilic polarity switch of LAF-XP carriers upon endosomal protonation, triggering dissociation of the PEG lipids and deshielding of the polyplex. Full article

Background: Betulins (betulin, betulinic acid and lupeol) demonstrated antitumor and chemopreventive activity but showed low bioavailability due to their self-aggregation in hydrophilic environments. To overcome these disadvantages, their incorporation into lipid nanoformulations (PEGylated liposomes and Lipid Nanostructured Carriers (NLCs)) has proven to represent a viable solution. Objectives: The purpose of this study is to evaluate the size and incorporation rate of these molecules in nanoformulations, as well as their delivery and metabolic fate (pure betulinic acid versus a standardized extract, TT) relative to Doxorubicin using an in vivo protocol. The investigation extended our previous in vitro investigations towards an in vivo evaluation of antitumor activity, metabolic fate and toxicity in Wistar rats bearing Walker 256 carcinoma tumors over 21 days. Since previous studies used oral or intratumor administration, this exploratory study applied intravenous administration via microbubble-assisted sonoporation, considering its higher relevance for translational studies. Methods: The delivery and metabolic fate of the parent molecules, the identification of their fragments and metabolites using UHPLC-QTOF-ESI⁺MS were investigated, along with the identification of some toxicity biomarkers in rat plasma, tumor tissues and urine. Results: Preferential accumulation of Doxorubicin in tumors was observed compared to betulinic acid and TT components, as well as their persistence in plasma or elimination in urine. Compared to PEGylated liposomes, NLC formulations (especially NLC Doxo) induced a lower survival rate, a decreased bioavailability and increased toxicity by around 20%. Conclusions: These data are a starting point and complement the contrast-enhanced imaging and histology evaluations, which may contribute to the actual knowledge about the in vivo fate of betulins. Full article

Background: Using natural substances for cancer therapy has attracted considerable interest due to their safety and reduced systemic toxicity. Nigella sativa (NS) oil, a traditional natural oil rich in bioactive compounds, possesses significant therapeutic potential. Brucine (BR), an alkaloid, exhibits potent cytotoxicity against various cancer cell lines; however, its poor selectivity and high systemic toxicity limit its clinical application. Objective: To overcome these challenges, this study aimed to enhance drug delivery and improve therapeutic efficacy. Method: A PEGylated nanoemulsion (NE) incorporating NS and BR was developed and characterized for particle size, size distribution, zeta potential, viscosity, and drug content. The in vitro release of BR was evaluated both with and without serum incubation. A quantitative amount of serum protein associated with the surface of the NE was estimated, and a hemolytic safety assay was carried out. Finally, an in vitro cytotoxicity study was conducted, and the in vivo anti-tumor effect of the developed PEGylated BR-loaded NE was evaluated and compared with its naked counterpart. Result: The developed PEGylated BR-loaded NE possessed favorable characteristics as a nanocarrier for parenteral administration, with a particle size of 188.5 nm, a zeta potential of −1.61, a viscosity of 3.4 cP, and 99% drug content uniformity. It released up to 60.4% of BR over 12 h, while only 18.4 µg/µmol of the total lipids were adsorbed on the surface of the formulation, compared with 54.5 µg/µmol for the naked counterpart. The PEGylated NE was safe, inducing less than 5% of hemolysis, and displayed substantial inhibition of MDA cell growth. Conclusions: The PEGylated NE achieved a significant reduction in tumor volume, suggesting that PEGylated NE may serve as a promising platform for enhancing anti-tumor activity. Full article

Background: 1,4-bis-L/L methionine–conjugated mitoxantrone–amino acid conjugate (L/LMet-MAC) inhibits topoisomerase IIα and enhances tumor cytotoxicity, but its short half-life limits therapeutic application. Objective: To improve the pharmacokinetics and antitumor efficacy of L/LMet-MAC through liposomal encapsulation. Methods: PEGylated DSPC liposomes containing EPG or prepared via the ammonium sulfate gradient method were employed to encapsulate L/LMet-MAC. Encapsulation efficiency, drug-to-lipid ratio, and serum stability were assessed. Pharmacokinetics, antitumor efficacy, and systemic safety were further evaluated in vivo. Results: L/LMet-MAC encapsulated in PEGylated DSPC liposomes containing EPG or prepared using the ammonium sulfate gradient method has high encapsulation efficiency. Further studies show that PEGylated DSPC liposomes prepared with the ammonium sulfate gradient approach display an efficient D/L ratio and serum stability as well as improved pharmacokinetics and enhanced antitumor efficacy while mitigating the side effects of L/LMet-MAC. Conclusions: PEGylated DSPC liposomes prepared using an ammonium sulfate gradient showed favorable performance for delivering L/LMet-MAC. Full article

As part of an antimicrobial resistance (AMR) strategy, we have prepared α,ε-N,N′-di-stearoyl lysine-based amide lipids to improve the chemical and biological stabilities of nanoparticles. Those amide lipids incorporated a variety of head groups, including lipid A-binding ligand (polymyxin B nonapeptide, PMBN) for bacterial targeting and sialic acid as an alternative to PEGylation for phagocytosis resistance. The study demonstrated that the PMBN-liposome specifically targeted lipid A-containing Gram-negative Acinetobacter baumannii bacteria, but not Gram-positive Staphylococcus aureus. However, such interaction was interrupted by the adsorption of serum proteins onto liposomes, demonstrating the complexity and challenge of targeted delivery. As expected, slower uptake of sialic acid-liposomes by human leukemia monocytic THP-1 cells was observed, suggesting their resistance to phagocytosis. Additionally, in a mouse model, the sialic acid-containing liposomes showed more favorable biodistribution and longer retention time than the comparable phospholipid-only liposomes. We observed that both sialic acid-incorporated and PEGylated liposomes distributed over the whole mouse bodies and remained for over 48 h. In contrast, the phospholipid-only liposomes rapidly migrated to the liver (5–15 min). In conclusion, although this study did not achieve bacteria-targeted liposome delivery, it provided evidence that the sialic acid-amide lipid can serve as an alternative to PEGylation in future nanomedicine. Full article

Liposomes are lipid bilayer vesicles that are highly biocompatible, able to interact with the cell membrane, and able to release their cargo easily. The improvement of the physicochemical properties of liposomes, such as surface charge, lipid composition, and functionalization, makes these vesicles eligible delivery nanosystems for the gene therapy of many pathological conditions. In the present study, pre-formulation analysis was conducted to develop liposomes that facilitate the delivery of nucleic acids to neuronal cells, with the aim of future delivery of a CRISPR/Cas9 system designed to silence genes responsible for autosomal dominant neurodegenerative disorders. To this aim, different nucleic acid cargo models, including λ phage DNA, plasmid DNA, and mRNA encoding GFP, were considered. Liposomes with varying lipid compositions were produced using the ethanol injection method and analyzed for their dimensional stability and ability to interact with DNA. The selected formulations were tested in vitro using a neuroblastoma cell line (SH-SY5Y) to evaluate their potential toxicity and the ability to transfect cells with a DNA encoding the green fluorescent protein (pCMV-GFP). Among all formulations, the one containing phosphatidylcholine, phosphatidylethanolamine, pegylated 1,2-distearoyl-sn-glycero-3-phosphethanolamine, cholesterol, and dioctadecyl-dimethyl ammonium chloride (in the molar ratio 1:2:4:2:2) demonstrated the highest efficiency in mRNA delivery. Although this study was designed with the goal of ultimately enabling the delivery of a CRISPR/Cas9 system for treating autosomal dominant neurodegenerative disorders such as polyglutamine spinocerebellar ataxias (SCAs), CRISPR/Cas9 components were not delivered in the present work, and their application remains the objective of future investigations. Full article

Liposomes are nanoscale, spherical vesicles composed of phospholipid bilayers, typically ranging from 50 to 200 nm in diameter. Their unique ability to encapsulate both hydrophilic and hydrophobic molecules makes them powerful nanocarriers for drug delivery, diagnostics, and vaccine formulations. Several FDA-approved formulations such as Doxil^® (Baxter Healthcare Corporation, Deerfield, IL, USA), AmBisome^® (Gilead Sciences, Inc., Foster City, CA, USA), and Onivyde^® (Ipsen Biopharmaceuticals, Inc., Basking Ridge, NJ, USA) highlight their clinical significance. This review provides a comprehensive synthesis of how molecular dynamics (MD) simulations, particularly coarse-grained (CG) and atomistic approaches, advance our understanding of liposomal membranes. We explore key membrane biophysical properties, including area per lipid (APL), bilayer thickness, segmental order parameter ($S_{CD}$), radial distribution functions (RDFs), bending modulus, and flip-flop dynamics, and examine how these are modulated by cholesterol concentration, PEGylation, and curvature. Special attention is given to curvature-induced effects in spherical vesicles, such as lipid asymmetry, interleaflet coupling, and stress gradients across the leaflets. We discuss recent developments in vesicle modeling using tools such as TS2CG, CHARMM-GUI Martini Maker, and Packmol, which have enabled the simulation of large-scale, compositionally heterogeneous systems. The review also highlights simulation-guided strategies for designing stealth liposomes, tuning membrane permeability, and enhancing structural stability under physiological conditions. A range of CG force fields, MARTINI, SPICA, SIRAH, ELBA, SDK, as well as emerging machine learning (ML)-based models, are critically assessed for their strengths and limitations. Despite the efficiency of CG models, challenges remain in capturing long-timescale events and atomistic-level interactions, driving the development of hybrid multiscale frameworks and AI-integrated techniques. By bridging experimental findings with in silico insights, MD simulations continue to play a pivotal role in the rational design of next-generation liposomal therapeutics. Full article

Chronic infection with the hepatitis B virus (HBV) results in over 1 million deaths annually. Although currently licensed treatments, including pegylated interferon-α and nucleoside/nucleotide analogs, can inhibit viral replication, they rarely eradicate covalently closed circular DNA (cccDNA) reservoirs. Moreover, vaccination does not offer therapeutic benefit to already infected individuals or non-responders. Consequently, chronic infection is maintained by the persistence of cccDNA in infected hepatocytes. For this reason, novel therapeutic strategies that permanently inactivate cccDNA are a priority. Obligate heterodimeric transcription activator-like effector nucleases (TALENs) provide the precise gene-editing needed to disable cccDNA. To develop this strategy using a therapeutically relevant approach, TALEN-encoding mRNA targeting viral core and surface genes was synthesized using in vitro transcription with co-transcriptional capping. TALENs reduced hepatitis B surface antigen (HBsAg) by 80% in a liver-derived mammalian cell culture model of infection. In a stringent HBV transgenic murine model, a single dose of hepatotropic lipid nanoparticle-encapsulated TALEN mRNA lowered HBsAg by 63% and reduced viral particle equivalents by more than 99%, without evidence of toxicity. A surveyor assay demonstrated mean in vivo HBV DNA mutation rates of approximately 16% and 15% for Core and Surface TALENs, respectively. This study presents the first evidence of the therapeutic potential of TALEN-encoding mRNA to inactivate HBV replication permanently. Full article

Background: Lipid nanoparticles (LNPs) represent one of the most effective non-viral vectors for nucleic acid delivery and have demonstrated clinical success in siRNA therapies and mRNA vaccines. While considerable research has focused on optimizing ionizable lipids and helper lipids, the impact of PEGylated lipid content on LNP-mediated mRNA delivery, especially in terms of in vitro transfection efficiency and in vivo performance, remains insufficiently understood. Methods: In this study, LNPs were formulated using a self-synthesized ionizable lipid and varying molar ratios of DMG-PEG2000. Nanoparticles were prepared via nanoprecipitation, and their physicochemical properties, mRNA encapsulation efficiency, cellular uptake, and transfection efficiency were evaluated in HeLa and DC2.4 cells. In vivo delivery efficiency and organ distribution were assessed in mice following intravenous administration. Results: The PEGylated lipid content exerted a significant influence on both the in vitro and in vivo performance of LNPs. A bell-shaped relationship between PEG content and transfection efficiency was observed: 1.5% DMG-PEG2000 yielded optimal mRNA transfection in vitro, while 5% DMG-PEG2000 resulted in the highest transgene expression in vivo. This discrepancy in optimal PEG content may be attributed to the trade-off between cellular uptake and systemic circulation: lower PEG levels enhance cellular internalization, whereas higher PEG levels improve stability and in vivo bioavailability at the expense of cellular entry. Furthermore, varying the PEG-lipid content enabled the partial modulation of organ distribution, offering a formulation-based strategy to influence biodistribution without altering the ionizable lipid structure. Conclusions: This study highlights the critical role of PEGylated lipid content in balancing nanoparticle stability, cellular uptake, and in vivo delivery performance. Our findings provide valuable mechanistic insights and suggest a straightforward formulation-based strategy to optimize LNP/mRNA systems for therapeutic applications. Full article

mRNA-based drug development is revolutionizing tumor therapies by enabling precise cancer immunotherapy, tumor suppressor gene restoration, and genome editing. However, the success of mRNA therapies hinges on efficient delivery systems that can protect mRNA from degradation and facilitate its release into the cytoplasm for translation. Despite the emergence of lipid nanoparticles (LNPs) as a clinically advanced platform for mRNA delivery, the efficiency of endo/lysosomal escape still represents a substantial bottleneck. Here, we summarize the intracellular fate of mRNA-loaded LNPs, focusing on their internalization pathways and processing within the endo-lysosomal system. We also discuss the impact of endo-lysosomal processes on mRNA delivery and explore potential strategies to improve mRNA escape from endo-lysosomal compartments. This review focuses on molecular engineering strategies to enhance LNP-mediated endo/lysosomal escape by optimizing lipid composition, including ionizable lipids, helper lipids, cholesterol, and PEGylated lipids. Additionally, ancillary enhancement strategies such as surface coating and shape management are discussed. By comprehensively integrating mechanistic insights into the journey of LNPs within the endo-lysosome system and recent advances in lipid chemistry, this review offers valuable inspiration for advancing mRNA-based cancer therapies by enabling robust protein expression. Full article

A new method of the design of stimuli-sensitive multiliposomal containers for encapsulation and controlled drug release is described. Despite quite a wide choice of pH-sensitive containers, there is still a considerable challenge to synthesize those that respond quickly to small variations in pH and release most of the encapsulated drug in a short time. The suggested AMS-containing multiliposomal complexes demonstrated an excellent rate of encapsulated substance release under altering the pH of the outer solution. To improve the efficiency of the delivery of bioactive compounds to target cells and to increase the therapeutic effect, pH-sensitive liposomes were concentrated on the surface of the carrier- PEG-coated cationic liposomes. A pH-sensitive ampholytic derivative of cholan-24-oic acid embedded into the membrane of anionic liposomes allowed the rapid release of the cargo in the areas of low pH, such as tumors, inflammation sites, etc. The diameter of the complexes was optimized for passive targeting and typically ranged from 250 to 400 nm. The biodegradability of liposomes ensured enzymatic destruction of the multiliposomal containers and their elimination from the body after performing their transport function. The multiliposomal complexes and products of their biodegradation demonstrated low cytotoxicity. The composition of multiliposomal complexes, in particular, the amount of PEGylated lipid in the bilayer, was estimated to provide a high speed of the cargo release upon changing the pH. The novel developed pH-sensitive containers show potential for biomedical applications. Full article

Background/Objectives: [6]-Gingerol ([6]-G), a bioactive compound derived from Zingiber officinale (ginger), exhibits strong anticancer potential but is hindered by poor aqueous solubility and low bioavailability. This study aimed to develop and evaluate PEGylated liposomal [6]-G (6-G-Lip) to enhance its stability, bioavailability, and chemopreventive efficacy in benzo[a]pyrene (BaP)-induced lung carcinogenesis. Methods: 6-G-Lip was synthesized using a modified thin-film hydration technique and characterized for size, polydispersity index (PDI), zeta potential, encapsulation efficiency (EE%), and release kinetics. The chemopreventive effects were assessed in BaP-induced lung cancer in Swiss albino mice, with prophylactic 6-G-Lip administration from two weeks before BaP exposure through 21 weeks. Cancer biomarkers, antioxidant enzyme activity, reactive oxygen species (ROS) generation, induction of apoptosis, and histopathological alterations were analyzed. Results: 6-G-Lip exhibited a particle size of 129.7 nm, a polydispersity index (PDI) of 0.16, a zeta potential of −18.2 mV, and an encapsulation efficiency (EE%) of 91%, ensuring stability and effective drug loading. The formulation exhibited a controlled release profile, with 26.5% and 47.5% of [6]-G released in PBS and serum, respectively, at 72 h. 6-G-Lip significantly lowered cancer biomarkers, restored antioxidant defenses (SOD: 5.60 U/min/mg protein; CAT: 166.66 μm H₂O₂/min/mg protein), reduced lipid peroxidation (MDA: 3.3 nm/min/mg protein), and induced apoptosis (42.2%), highlighting its chemopreventive efficacy. Conclusions: This study is the first to prepare, characterize, and evaluate PEGylated [6]-G-Lip for the chemoprevention of lung cancer. It modulates oxidative stress, restores biochemical homeostasis, and selectively induces apoptosis. These findings support 6-G-Lip as a promising nanotherapeutic strategy for cancer prevention. Full article