Manufacturing process of liposomal Formation: A coarse-grained molecular dynamics simulation.

A method of producing liposomes has been previously developed using a continuous manufacturing technology that involves a co-axial turbulent jet in co-flow. In this study, coarse-grained molecular dynamics (CG-MD) simulations were used to gain a deeper understanding of how the self-assembly process of liposomes is affected by the material attributes (such as the concentration of ethanol) and the process parameters (such as temperature), while also providing detailed information on a nano-scale molecular level. Specifically, the CG-MD simulations yield a comprehensive internal view of the structure and formation mechanisms of liposomes containing DPPC, DPPG, and cholesterol molecules. The importance of this work is that structural details on the molecular level are proposed, and such detail is not possible to obtain through experimental studies alone. The assessment of structural properties, including the area per lipid, diffusion coefficient, and order parameters, indicated that a thicker bilayer was observed at higher ethanol concentrations, while a thinner bilayer was present at higher temperatures. These conditions led to more water penetrating the interior of the bilayer and an unstable structure, as indicated by a larger contact area between lipids and water, and a higher coefficient of lipid lateral diffusion. However, stable liposomes were found through these evaluations at lower ethanol concentrations and/or lower process temperatures. Furthermore, the CG-MD model was further compared and validated with experimental and computational data including liposomal bilayer thickness and area per lipid measurements.

High throughput microfluidics-based synthesis of PEGylated liposomes for precise size control and efficient drug encapsulation.

The low scalability and reproducibility of existing synthesis methods have hindered the translation of liposome nanoparticles as carriers for targeted drug delivery from conventional laboratory techniques to mass production. To this end, in this study, we present a high-throughput microfluidics-based approach for the synthesis of PEGylated liposomes with a primary focus on achieving precise size control and efficient encapsulation of hydrophobic drug molecules. In this platform, liposomes were self-assembled through a controllable mixing of lipids (EYPC, cholesterol, and DSPE-PEG 2000) dissolved in ethanol and an aqueous solution. The key parameters, including the chip design, total flow rate, flow rate ratio, lipid concentrations, as well as variations in buffer (HEPES and NaCl) and solvent composition (commercial and reagent-grade ethanol) were explored in detail. Through comprehensive parametric studies, we gained valuable insights into the influence of these variables on the size distribution of liposomes and succeeded in producing highly reproducible liposomes ranging from approximately 60 nm (corresponding to small unilamellar vesicles) to 150 nm (representing large unilamellar vesicles), all while maintaining a polydispersity index (PDI) of less than 0.2. To assess the encapsulation efficiency of hydrophobic drug molecules, Nile red (NR) was employed as a surrogate. We meticulously examined the impact of NR concentration on the drug encapsulation process, resulting in up to 74% drug encapsulation efficiency within the PEGylated liposomes. This research offers crucial advances in liposome synthesis and drug delivery, providing a high-throughput, controllable method for PEGylated liposomes with potential in pharmaceutical and biomedical fields.

Thin-Film Hydration Followed by Extrusion Method for Liposome Preparation.

One of the simplest ways to prepare liposomes in a research laboratory is the thin-film hydration method followed by extrusion. This method involves making a thin lipid film in a round-bottom flask by the removal of organic solvent. Upon the addition and agitation of the dispersion medium, heterogeneous liposomes are formed. Finally, after extrusion through polycarbonate membranes, homogeneous small liposomes are obtained.

Biomembrane-based nanostructures for cancer targeting and therapy: From synthetic liposomes to natural biomembranes and membrane-vesicles.

The translational success of liposomes in chemotherapeutics has already demonstrated the great potential of biomembrane-based nanostructure in effective drug delivery. Meanwhile, increasing efforts are being dedicated to the application of naturally derived lipid membranes, including cellular membranes and extracellular vesicles in anti-cancer therapies. While synthetic liposomes support superior multifunctional flexibility, natural biomembrane materials possess interesting biomimetic properties and can also be further engineered for intelligent design. Despite being remarkably different from each other in production and composition, the phospholipid bilayer structure in common allows liposomes, cell membrane-derived nanomaterials, and extracellular vesicles to be modified, functionalized, and exploited in many similar manners against challenges posed by tumor-targeted drug delivery. This review will summarize the recent advancements in engineering the membrane-derived nanostructures with "intelligent" modules to respond, regulate, and target tumor cells and the microenvironment to fight against malignancy. We will also discuss perspectives of combining engineered functionalities with naturally occurring activity for enhanced cancer therapy.

Comparison of two routes of administration of a cationic liposome formulation for a prophylactic DC vaccination in a murine melanoma model.

Dendritic cell (DC) vaccination can be achieved via straight loading of vaccine into DCs ex vivo or administration to DCs in vivo. However, there is no certain consensus on which approach is preferable, and each strategy has its advantages and disadvantages, which affect the efficacy and safety of vaccines. It will also be more complicated when a vaccine delivery system is included. In this study, the efficacy of ex vivo pulsed DC-based vaccine compared with in vivo subcutaneous administration of a cationic liposomes (CLs) formulation containing gp100 antigen (gp100-CLs) was evaluated in a murine melanoma model. In combination with an anti-PD-1 antibody, the ex vivo approach of gp100-CLs yielded a significant (P < 0.01) increase in the number of antigen-specific tumors infiltrated lymphocytes (TILs) with a significant upregulation of IFN-γ (P < 0.0001) and PD-1 (P < 0.0001) expression level. They also dampened the function of immunosuppressive regulatory T cells (Tregs) via significant downregulation of IL-10 and TGF-ß (P < 0.0001) expression level compared to in vivo approach in the tumor microenvironment (TME). Furthermore, prophylactic immunization with gp100-CLs pulsed DCs ex vivo delayed tumor growth and induced the survival benefit over in vivo immunization. Collectively, the ex vivo DC-based vaccination pulsed with gp100 encapsulated in liposomes synergizes with anti-PD-1 antibody and represents a preferable approach against melanoma.

Acriflavine-loaded solid lipid nanoparticles: preparation, physicochemical characterization, and anti-proliferative properties.

Acriflavine (ACF) is an antiseptic compound with the potential antitumor activity which is used for the fluorescent staining of RNA due to its dominant fluorescent emission at ∼515 nm. Here, solid lipid nanoparticles (SLNs) containing ACF (ACF-SLNs) were prepared and their physicochemical properties, potential geno/cytotoxicity, as well as the fluorescent properties were investigated. FITC-annexin V/PI staining and cell cycle assays were carried out to find the type of cellular death caused. Particle size analysis and SEM images revealed that spherical ACF-SLNs had a homogeneous dispersion with a mean diameter of 106 ± 5.7 nm. Drug loading (DL) of 31.25 ± 4.21 mg/mL and high encapsulation efficiency (EE%) (89.75 ± 5.44) were found. ACF-SLNs physically were relatively stable in terms of dispersion, size, and EE. The uptake study demonstrated the potential use of fluorescent ACF-SLNs in bio-distribution studies. MTT assay showed that plain ACF could induce growth inhibition of A549 cells with IC50 of 8.5, 6, and 4.5 µMol after 24, 48, and 72 hours, respectively, while ACF-SLNs had stable cytotoxic effects after 48 hours. ACF-SLNs induced remarkable apoptosis and even necrosis after 48 h. Conclusively, ACF-SLNs with acceptable physicochemical features showed increased bioimpacts after 48 h compared to plain ACF.

Polyethylene glycol triggers the anti-cancer impact of curcumin nanoparticles in sw-1736 thyroid cancer cells.

Curcumin has been recognized as an effective anticancer agent. However, due to its hydrophobic property, the cell absorption is not satisfied. Herein, the curcumin nanoparticles were prepared in the presence of polyethylene glycol 6000 (PEG6000) to reduce its elimination by immune system. For first time, not only the curcumin was encapsulated within the niosome nanoparticles modified by PEG, there are no reports related to the anticancer property of curcumin against thyroid cancers. The nanoparticles was developed and its anticancer was studied on sw-1736 cancer cell line. The nanoparticles were examined by scanning electron microscopy (SEM) and dynamic light scattering (DLS). Also, the release profile of curcumin, the IC50 concentration, the radical amount and the gene expression were evaluated. The optimized nanoparticles showed a diameter of 212 ± 31 nm by SEM and the encapsulation efficiency and loading capacity of 76% and 16.8% respectively. DLS confirmed the polydispersity index (PDI) of 0.596 and the release model was shown a sustained release with the delivery of 68% curcumin after 6 days. Also, the nanoparticles indicated the higher storage stability at 4 °C. After the cell treatment, the apoptotic bodies were appeared and IC50 was obtained as 0.159 mM. Moreover, the generated radicals by the treated cells was 86% after 72 h and the gene pattern indicated the bax/bcl2 ratio of 6.83 confirming the apoptosis effect of the nanoparticles. The results approved the nanoparticles could be suggested as an anticancer drug candidate for thyroid cancers. The encapsulated curcumin within the niosome nanoparticles modified with PEG, could be released and up-taken by the thyroid cancer cell line due to the same hydrophobic property of cell membrane and the niosome particles. The reaction between curcumin and cellular components generates radicals and activates the apoptotic pathway. The corresponding reaction finally makes cell death.

Cyanine Dyes for Photo-Thermal Therapy: A Comparison of Synthetic Liposomes and Natural Erythrocyte-Based Carriers.

Cyanine fluorescent dyes are attractive diagnostic or therapeutic agents due to their excellent optical properties. However, in free form, their use in biological applications is limited due to the short circulation time, instability, and toxicity. Therefore, their encapsulation into nano-carriers might help overcome the above-mentioned issues. In addition to indocyanine green (ICG), which is clinically approved and therefore the most widely used fluorescent dye, we tested the structurally similar and cheaper alternative called IR-820. Both dyes were encapsulated into liposomes. However, due to the synthetic origin of liposomes, they can induce an immunogenic response. To address this challenge, we proposed to use erythrocyte membrane vesicles (EMVs) as "new era" nano-carriers for cyanine dyes. The optical properties of both dyes were investigated in different biological relevant media. Then, the temperature stability and photo-stability of dyes in free form and encapsulated into liposomes and EMVs were evaluated. Nano-carriers efficiently protected dyes from thermal degradation, as well as from photo-induced degradation. Finally, a hemotoxicity study revealed that EMVs seem less hemotoxic dye carriers than clinically approved liposomes. Herein, we showed that EMVs exhibit great potential as nano-carriers for dyes with improved stability and hemocompatibility without losing excellent optical properties.

Quality by design (QbD) in the formulation and optimization of liquid crystalline nanoparticles (LCNPs): A risk based industrial approach.

The intersection of lipid-based nanoparticles and lyotropic liquid crystals has provided a novel type of nanocarrier system known as 'lipid-based lyotropic liquid crystals' or 'liquid crystalline nanoparticles' (LCNPs). The unique advantages and immense popularity of LCNPs can be exploited in a better way if the formulation of LCNPs is done using the approach of quality by design (QbD). QbD is a systematic method that can be utilized in formulation development. When QbD is applied to LCNPs formulation, it will proffer many unique advantages, such as better product and process understanding, the flexibility of process within the design space, implementation of more effective and efficient control strategies, easy transfer from bench to bedside, and more robust product. In this work, the application of QbD in the formulation of LCNPs has been explored. The elements of QbD, viz. quality target product profile, critical quality attributes, critical material attributes, critical process parameters, quality risk management, design of experiments, and control strategy for the development of LCNPs have been explained in-depth with case studies. The present work will help the reader to understand the nitty-gritties in the application of QbD in the formulation of LCNPs, and provide a base for QbD-driven formulation of LCNPs with a regulatory perspective.

Topical nanocarriers for management of Rheumatoid Arthritis: A review.

Rheumatoid arthritis (RA) is a systemic autoimmune disease manifested by chronic joint inflammation leading to severe disability and premature mortality. With a global prevalence of about 0.3%-1% RA is 3-5 times more prevalent in women than in men. There is no known cure for RA; the ultimate goal for treatment of RA is to provide symptomatic relief. The treatment regimen for RA involves frequent drug administration and high doses of NSAIDs such as indomethacin, diclofenac, ibuprofen, celecoxib, etorcoxib. These potent drugs often have off target effects which drastically decreases patient compliance. Moreover, conventional non-steroidal anti-inflammatory have many formulation challenges like low solubility and permeability, poor bioavailability, degradation by gastrointestinal enzymes, food interactions and toxicity. To overcome these barriers, researchers have turned to topical route of drug administration, which has superior patience compliance and they also bypass the first past effect experienced with conventional oral administration. Furthermore, to enhance the permeation of drug through the layers of the skin and reach the site of inflammation, nanosized carriers have been designed such as liposomes, nanoemulsions, niosomes, ethosomes, solid lipid nanoparticles and transferosomes. These drug delivery systems are non-toxic and have high drug encapsulation efficiency and they also provide sustained release of drug. This review discusses the effect of formulation composition on the physiochemical properties of these nanocarriers in terms of particle size, surface charge, drug entrapment and also drug release profile thus providing a landscape of topically used nanoformulations for symptomatic treatment of RA.

Robotics, microfluidics, nanotechnology and AI in the synthesis and evaluation of liposomes and polymeric drug delivery systems.

The field of nanotechnology and personalised medicine is undergoing drastic changes in the approach and efficiency of experimentation. The COVID-19 pandemic has spiralled into mass stagnation of major laboratories around the globe and led to increased investment into remote systems for nanoparticle experiments. A significant number of laboratories now operate using automated systems; however, the extension to nanoparticle preparation and artificial intelligence-dependent databases holds great translational promise. The strive to combine automation with artificial intelligence (AI) grants the ability to optimise targeted therapeutic nanoparticles for unique cell types and patients. In this perspective, the current and future trends of automated approaches to nanomedicine synthesis are discussed and compared with traditional methods.

Combinatorial liposomes of berberine and curcumin inhibit biofilm formation and intracellular methicillin resistant Staphylococcus aureus infections and associated inflammation.

The increase in drug-resistant strains of Staphylococcus aureus, especially methicillin-resistant S. aureus (MRSA), has led to an increased rate of infection-related mortality. The emergence of drug resistance has rendered many antibiotics ineffective. The poor penetration and retention of antibiotics in mammalian cells lead to recurrent latent infections. Thus, there is an increasing need for biodegradable, non-toxic anti-infectives that are effective in treating MRSA infections. Phytochemicals such as berberine (BBR) and curcumin (CCR) have long been explored for their antibacterial activities, but their efficacy is often limited due to low bioavailability, water solubility, and poor cell penetration. When used in combination these antimicrobials did not show any synergistic effect against MRSA. Here, both of them were co-encapsulated in liposomes (BCL) and evaluated for biocompatibility, synergistic antimicrobial activity, intracellular infections, associated inflammation, and on biofilms formed by MRSA. Co-encapsulation of BBR and CCR in liposomes decreased their MICs by 87% and 96%, respectively, as compared to their free forms with a FICI of 0.13, indicating synergy between them. BCL inhibited the growth of MRSA and prevented biofilm formation better than free drugs. Co-culture studies showed that intracellular infection was reduced to 77% post BCL treatment. It also reduced the production of pro-inflammatory cytokines by macrophages following infection. The liposomes were found to be five times more efficient than clindamycin and can be used as a potential antimicrobial carrier against intracellular infections.

Preparation and physicochemical characterization of elastic liposomes: a road-map library for their design.

Elastic liposomes consist of phospholipids and of surfactants, could be considered as promising nanotechnological platforms for skin drug delivery. The aim of the present study was the formation of elastic liposomes by thin film hydration method, using different phospholipids and surfactants, in order to determine the effect of the components on their physical characteristics and on their physical stability. Physical properties of elastic liposomes were evaluated using dynamic light scattering (DLS)method. The particle size at the day of their preparation, was ranged between small and large unilamellar vesicles (SUVs and LUVs), dependent on the hydrophilicity of the surfactant used, while their PDI (Poly Dispersity Index) value was close to zero, indicating monodispersed systems. Physical stability study involved the measure of particle size, as a quantifiable physical property, at selected times over a 30-days period, at storage conditions: (i) 4 °C, (ii) 25 °C, iii) 45 °C, suggested that refrigerated conditions promote physical stability, while high temperatures induce aggregation. According to the physical stability study elastic liposomes composed ofTween80 were found to bemore stable than those composed of Span80, at ambient conditions. The goal of our investigation was centred to the development and evaluation of a well know liposomal category i.e. elastic liposomes, by modified their composition with common surfactants (i.e. Span and/or Tween), creating, a new liposomal class namely, elastic lipo-niosomes. To the best of knowledge this the first time that these hybrid vesicles appeared in the literature exhibiting the aforementioned category lipid/surfactants and molar ratios.

Bulk and Microfluidic Synthesis of Stealth and Cationic Liposomes for Gene Delivery Applications.

This chapter describes the synthesis of stealth and cationic liposomes and their complexation with plasmid DNA to generate lipoplexes for gene delivery applications. Two techniques are presented: a top-down approach which requires a second step of processing for downsizing the liposomes (i.e., ethanol injection method) and a microfluidic technique that explores the diffusion of ethanol in water to allow the proper lipid self-assembly. The synthesis of stealth liposomes is also a challenge since the use of poly(ethylene glycol) favors the formation of oblate micelles. In this protocol, the stealth cationic liposome synthesis by exploring the high ionic strength to overcome the formation of secondary structures like micelles is described. Finally, the electrostatic complexation between cationic liposomes and DNA is described, indicating important aspects that guarantee the formation of uniform lipoplexes.

Improving protection effects of eucalyptol via carboxymethyl chitosan-coated lipid nanoparticles on hyperglycaemia-induced vascular endothelial injury in rats.

Hyperglycaemia is responsible for the major pathophysiological factor of diabetes-associated vascular endothelial injury, which mainly resulted from the disturbance of equilibrium between ROS generation and elimination. Eucalyptol was verified with exact anti-oxidation effects via stimulating the secretion of endogenous antioxidant enzymes against ROS. However, the volatility, instability and poor water solubility of eucalyptol limited its pharmacological activities in vivo. In this study, we developed carboxymethyl chitosan-coated lipid nanoparticles for eucalyptol (CMC/ELN) to facilitate oral administration. A thin lipid film dispersion method was used to prepare the ELN. After CMC coating, the diameter of ELN increased from 166 nm to 177 nm and charge reversal was observed. The nanocarrier enhanced the protective effects of eucalyptol both in the high level of glucose (HG)-damaged HUVECs and endothelial injury in type I diabetes mellitus (T1DM) rat model. Furthermore, the mechanism of eucalyptol on the promotion of Nrf2 and HO-1 and reduction on Keap1 expression have been verified both in the in vitro and in vivo model. Besides, the pharmacokinetics data were verified the promotion of the oral eucalyptol absorption by the nanocarrier. Taken together, we established an optimal oral delivery system that promoted oral administration of eucalyptol to exert protective effects on hyperglycaemia-induced vascular endothelial injury.

Synthesis, anticancer activity and potential application of diosgenin modified cancer chemotherapeutic agent cytarabine.

Diosgenin (DG), a steroidal saponin, is mainly found in yam tubers. DG and its derivatives displayed significant pharmacological activities against inflammatory, hyperlipidemia, and various cancers. DG was selected to modify the cancer chemotherapeutic agent cytarabine (Ara-C) due to its anti-tumor activities as well as lipophilicity. After characterization, the biomembrane affinity and the kinetic thermal processes of the obtained DG-Ara-C conjugate were evaluated by differential scanning calorimetry (DSC). Thin hydration method with sonication was applied to prepare the DG-Ara-C liposomes without cholesterol since the DG moiety has the similar basic structure with cholesterol with more advantages. Dynamic Light Scattering (DLS) analysis and cytotoxic analysis were employed to characterize the DG-Ara-C liposomes and investigate their biological activities, respectively. The results indicated that DG changed the biomembrane affinity of Ara-C and successfully replaced the cholesterol during the liposome preparation. The DG-Ara-C liposomes have an average particle size of around 116 nm with a narrow size distribution and revealed better anti-cancer activity against leukemia cells and solid tumor cells than that of free DG or Ara-C. Therefore, it can be concluded that DG displayed the potential application as an anti-cancer drug carrier to improve the bio-activities, since DG counted for a critical component in modulating the biomembrane affinity, preparation of liposome, and release of hydrophilic Ara-C from lipid vesicles.

Biotin and glucose co-modified multi-targeting liposomes for efficient delivery of chemotherapeutics for the treatment of glioma.

Glioma is one of the most common primary intracranial tumor, but the current treatments of glioma are far from satisfying. As the major treatment option for malignant glioma, chemotherapy has its own disadvantages, including low chemotherapeutic agents delivery across blood-brain barrier (BBB) and lack of specificity. Therefore, new approach permitting glioma targeting ability that can allow an efficient therapeutic delivery into the glioma regions is urgently required. Ligand-mediated liposomes have shown great potential for improving the efficiency of glioma treatment. In our study, the multi-targeting liposomes based on glucose and biotin were constructed for the first time. We synthesized two ligands (Glu3-Chol, Bio2-Chol), prepared three types of modified liposomes (Glu3-Lip, Bio2-Lip and Bio2 + Glu3-Lip) and evaluated the glioma-targeting ability of these liposomes which were using paclitaxel (PTX) as the model drug in vitro. Besides, the uptake mechanism of Bio2 + Glu3-Lip was investigated. PTX-loaded Bio2 + Glu3-Lip (PTX-Bio2 + Glu3-Lip) exhibited satisfactory targeting effect in Bend.3 and C6 cells in vitro, in which the cellular uptake of Bio2 + Glu3-Lip were 4.04- and 3.49-fold more than that of the uncoated liposomes (Lip). The results suggested the multi-targeting liposomes (Bio2 + Glu3-Lip) is a promising formulation for glioma, which was almost consistent with the results of in vivo imaging. In summary, we have designed and fabricated an effective delivery system to treat glioma.

Stability of Alkyl Chain-Mediated Lipid Anchoring in Liposomal Membranes.

Lipid exchange among biological membranes, lipoprotein particles, micelles, and liposomes is an important yet underrated phenomenon with repercussions throughout the life sciences. The premature loss of lipid molecules from liposomal formulations severely impacts therapeutic applications of the latter and thus limits the type of lipids and lipid conjugates available for fine-tuning liposomal properties. While cholesterol derivatives, with their irregular lipophilic surface shape, are known to readily undergo lipid exchange and interconvert, e.g., with serum, the situation is unclear for lipids with regular, linear-shaped alkyl chains. This study compares the propensity of fluorescence-labeled lipid conjugates of systematically varied lengths to migrate from liposomal particles consisting mainly of egg phosphatidyl choline 3 (EPC3) and cholesterol into biomembranes. We show that dialkyl glyceryl lipids with chains of 18-20 methylene units are inherently stable in liposomal membranes. In contrast, C16 lipids show some lipid exchange, albeit significantly less than comparable cholesterol conjugates. Remarkably, the C18 chain length, which confers noticeable anchor stability, corresponds to the typical chain length in biological membranes.

Protein kinase C inhibitor anchored BRD4 PROTAC PEGylated nanoliposomes for the treatment of vemurafenib-resistant melanoma.

Limited treatment options and development of resistance to targeted therapy within few months pose significant challenges in the treatment of BRAF-mutated malignant melanoma. Moreover, extensive angiogenesis and vasculogenic mimicry promote the rapid progression of disease. The purpose of this study was to develop a protein kinase C inhibitor anchored BRD4 PROTAC (ARV) loaded PEGylated nanoliposomes (LARPC). Palmitoyl-dl-carnitine chloride (PC) was used as a protein kinase C inhibitor to provide a cationic surface charge to LARPC. The formulation was characterized for particle size, zeta potential, drug release and various cell culture assays using HUVEC and vemurafenib resistant melanoma cells. The particle size of LARPC was found to be 105.25 ± 2.76 nm with a zeta potential of +26.6 ± 6.25 mV. Inhibition of angiogenesis was demonstrated by ARV and LARPC using human umbilical vein endothelial cells (HUVEC)-based matrigel basement membrane model. Additionally, LARPC demonstrated very low IC50 with promising inhibition of vasculogenic mimicry channel formation, cell migration as well as colony formation in vemurafenib-resistant melanoma cell lines. Hence, the outcome of this combination therapy indicated the suitability of LARPC as a potential and novel approach for eradicating vemurafenib-resistant melanoma.

Synthesis of defined oligohyaluronates-decorated liposomes and interaction with lung cancer cells.

In this work hyaluronic acid (HA) oligosaccharides with degree of polymerization (DP) 4, 6 and 8, obtained by enzymatic depolymerization of HA, were conjugated to a PEG-phospholipid moiety. The products (HA-DP4, HA-DP6 and HA-DP8) were used to prepare decorated liposomes. The cellular uptake of HA-DP4, HA-DP6 and HA-DP8-decorated fluorescently labelled liposomes was significantly higher (12 to 14-fold) in lung cancer cell lines with high CD44 expression than in those with low CD44 expression, suggesting a receptor-mediated entry of HA-conjugated formulations. Competition assays showed that the uptake followed this rank order: HA-DP8>HA-DP6>HA-DP4 liposomes. Moreover, they are capable of a faster interaction with CD44, followed by phagocytosis, than HA liposomes obtained from HA of higher molecular weight (4800 and 14800 Da). HA-DP4, HA-DP6 and HA-DP8-liposomes did not show cytotoxicity or inflammatory effects. Overall, we propose our new HA-DP oligosaccharides as biocompatible and effective tools for a potential drug delivery to CD44-positive cells.