Preparation Of Liposomes Research Articles

Electrical Conductivity as an Informative Factor of the Properties of Liposomal Systems with Naproxen Sodium for Transdermal Application.

Liposomal preparations play an important role as formulations for transdermal drug delivery; however, the electrical conductivity of these systems is sparingly evaluated. The aim of the study was to outline the range of the values of electrical conductivity values that may be recorded in the future pharmaceutical systems in the context of their viscosity. The electrical conductivity, measured by a conductivity probe of k = 1.0 cm-1, and the dynamic viscosity of liposomal and non-liposomal systems with naproxen sodium, embedded into a methylcellulose hydrophilic gel (0.25%), were compared with data from preparations without naproxen sodium in a range reflecting the naproxen sodium concentrations 0.1·10-2-9.5·10-2 mol/L. The specific conductivity covered a 1.5 μS·cm-1-5616.0 μS·cm-1 range, whereas the viscosity ranged from 0.9 to 9.4 mPa·s. The naproxen sodium highly influenced the electrical conductivity, whereas the dynamic viscosity was a moderate factor. The observed phenomena may be ascribed to the high mobility of sodium ions recruited from naproxen sodium and the relatively low concentrations of applied methylcellulose. The assembly of lecithin in liposomes may have lowered the specific conductivity of the systems with naproxen sodium. These measurements will be further developed for implementation as simple assays of the concentrations of active pharmaceutical ingredient in release experiments of preparations proposed for dermatological applications.

Sumac liposomes/mesenchymal stem cells fight methotrexate-induced nephrotoxicity in rats via regulating Nrf-2/Keap-1/HO-1 and apoptotic signaling pathways.

Methotrexate (MTX) is commonly employed in cancer treatment, but its clinical use is restricted due to the MTX-associated renal injury. This study investigates the combined potential of Rhus coriaria (sumac) and bone marrow mesenchymal stem cells (BMMSCs) against MTX-induced nephrotoxicity in rats. The high-resolution-liquid chromatography-mass spectrometry (HR-LC-MS) of sumac extract tentatively identified 22 phytochemicals, mostly flavonoids, anthocyanins, and steroids. Preparation of sumac liposomes attained a suitable particle size of 3041.33 ± 339.42 nm, a polydispersity index of 0.208 ± 0.086, and an encapsulation efficiency of 84.92 ± 3.47%. Rat BMMSCs were injected into the tail vein of the experimental rats (0.5 × 106 cells, intravenous [iv]) of seven treated groups. The experimental design relies on either pre- or posttreatment of rats with intraperitoneal (IP) sumac liposomes (SL) (200 mg/kg, daily with a dose of MTX (300 µg/kg/14 days). The histopathological examination and serum analysis of creatinine and urea revealed good results, besides regulating levels of oxidative stress and inflammatory markers. Additionally, a significant decrease in the gene expression levels of B-Cell Lymphoma 2 (Bcl-2) and caspases-3 and -9, a remarkable increase in the Bcl-2 Associated X-Protein (Bax), nuclear factor erythroid 2-related factor 2 (Nrf2), and heme-oxygenase 1 expression, and a downregulation of Kelch-like ECH-associated protein 1 (Keap1). Collectively, the coadministration of SL with BMMSCs might be a potent therapeutic strategy for attenuation of MTX-induced renal damage. The network pharmacology analysis identified the involved key hub genes as KEAP1, Nrf2, HMOX1, mitogen-activated protein kinase (MAPK1), nuclear factor-kappa B (NF-KB), interleukin-1 beta (IL-1B), and caspase-3. The docking results revealed strong binding affinities of 7-O-methyl-cyanidin-3-O-(2″-galloyl)-galactoside with Keap1 and amentoflavone with MAPK. These insights pave the way for future experimental validation and therapeutic development of sumac-based phytoconstituents against MTX-induced nephrotoxicity.

A Novel Delivery System for the Combined Use of Natural Ingredients: The Preparation of Berberine Hydrochloride-Matrine Liposomes and Preliminary Exploration of Their Anti-Tumor Activity.

Berberine hydrochloride (BH) extracted from Coptis chinensis (CC) and Matrine (MT) separated from Sophora flavescens (SF) are alkaloids with potent anti-bacterial, anti-inflammatory, and anti-tumor effects. Motivated by the clinical practice of using CC and SF together, we aimed to demonstrate that the synergistic application of the natural compounds BH and MT could enhance therapeutic effects and minimize side effects. Two types of liposomes, liposomes containing only BH (BH-LP) and liposomes containing both BH and MT (BH-MT-LP), were successfully prepared via the reverse evaporation method. The liposome preparation process was optimized by single-factor screening and the Box-Behnken experimental design method. The results showed that the liposomes had particle sizes in the range of 222.7 to 235.4 nm, polydispersity indicated in the range of 11.8% to 23.3%, and zeta potentials in the range of -35.9 to -31.1 mv. BH-MT-LP showed superior anti-tumor activity against MDA-MB-231, HepG-2, and HGC-27 cells in vitro. The incorporation of MT effectively promoted the anti-tumor effect of BH, while the controlled release from liposomes further enhanced the therapeutic efficacy of BH. Furthermore, based on the flow cytometry results, we speculated that BH-MT-LP might promote apoptosis by blocking the G1 phase of cells and inducing cell death. In conclusion, BH-MT-LP provides evidence for the combined use of natural compounds as a stable, safe, and practical drug delivery system for the treatment of potential cancers. Meanwhile, the successful preparation for BH-MT-LP also provides a new approach to the combined use of traditional Chinese medicine ingredients.

Preparation of transferrin-modified IR820-loaded liposomes and its effect on photodynamic therapy of breast cancer

ObjectiveTo prepare and characterize transferrin (Tf)-modified liposomes (Lipo) encapsulating the photosensitizing agent neoindocyanine green (IR820), and to investigate their effects on breast cancer 4T1 cells as well as in a breast cancer mouse model.MethodsPhotosensitive liposomes, IR820@Lipo and Tf-IR820@Lipo, were synthesized using thin film dispersion, with encapsulation efficiency assessed via UV detection. The physicochemical properties were analyzed using transmission electron microscopy (TEM) and particle size analysis. Uptake by breast cancer 4T1 cells was evaluated through confocal laser scanning microscopy and flow cytometry, while cell proliferation inhibition was measured using the CCK8 assay. Differences in intracellular fluorescence intensity were utilized to assess drug aggregation in vivo through small animal imaging techniques. The anticancer efficacy and potential side effects of the formulations were examined through pharmacodynamic studies conducted in vivo.ResultsThe mean particle sizes of IR820@Lipo and Tf-IR820@Lipo were found to be 84.30 ± 15.66 nm and 116.20 ± 14.68 nm respectively, with zeta potentials of −8.21 ± 2.06 mV for IR820@Lipo and −5.23 ± 1.19 mV for Tf-IR820@Lipo; TEM revealed that the liposomes exhibited a spheroid morphology with uniform distribution across samples; encapsulation efficiencies reached 86.38 ± 0.99% for IR820@Lipo and an impressive 93.81 ± 1.06% for Tf-IR820@Lipo; notably, Tf-IR820@Lipo significantly inhibited proliferation while promoting apoptosis of the 4T1 cells upon laser irradiation; reactive oxygen species (ROS) detection indicated enhanced fluorescence intensity within the treated cells under light exposure when utilizing both formulations; in vivo experiments demonstrated tumor accumulation of both IR820@Lipo and Tf-IR820@Lipo, indicating effective tumor targeting within a breast cancer mouse model; pharmacodynamic assessments revealed that Tf-IR820@Lipo exhibited superior inhibitory effects against breast cancer without causing liver or kidney dysfunctions in mice nor presenting significant toxic side effects overall.ConclusionGiven its high targeting capability, potent efficacy, and low toxicity profile, Tf-IR820@Lipo holds promise as a novel therapeutic agent for breast cancer treatment when combined with photodynamic therapy (PDT), potentially offering new avenues for patient management.

Preparation and Characterization of Hydrophobin 4-Coated Liposomes for Doxorubicin Delivery to Cancer Cells.

Background: The properties of nanoparticle surfaces are crucial in influencing their interaction with biological environments, as well as their stability, biocompatibility, targeting abilities, and cellular uptake. Hydrophobin 4 (HFB4) is a class II HFB protein produced by filamentous fungi that has a natural ability to self-assemble at hydrophobic-hydrophilic interfaces. The biocompatible, non-toxic, biodegradable, and amphipathic properties of HFB4 render it valuable for improving the solubility and bioavailability of hydrophobic drugs. We have investigated the physicochemical properties, cellular uptake, and anticancer effects of empty and Doxorubicin (Dox)-loaded HFB4 liposomes (HFB4L) and compared them to those of PEGylated liposomes (PPL). Methods: The Pichia pastoris KM71H strain was used for HFB4 purification. Liposomes were prepared through the thin film hydration method and characterized. The cytotoxic effects of free Dox, Dox-HFB4, and Dox-PPL were assessed in MCF7 cells using the SRB Assay. Results: All formulations showed good size homogeneity and a spherical shape. The HFB4 coating enhanced the physicochemical stability of Dox-HFB4L over 60 days at 4 °C without significantly affecting Dox release from HFB4L. It increased Dox release at pH 5.4 compared to pH 7.4, indicating higher delivery of drugs into acidic tumor environments, similar to Dox-PPL. While both formulations showed increased cellular uptake compared to free Dox, they exhibited a lower anticancer effect due to the sustained release of Dox. Notably, Dox-HFB4L displayed greater cytotoxicity than Dox-PPL in MCF7 cells. Conclusions: HFB4L may offer superior benefits in terms of delivering drugs to an acidic tumor environment in a stable, non-toxic, and sustained manner.

Preparation and characterization of moringin-loaded chitosan-coated liposomes and their antibacterial activity against Staphylococcus aureus

This study aimed to improve the stability of moringin and clarify the inhibitory mechanisms of moringin-loaded chitosan-coated liposomes (MR-CS-LPs) against Staphylococcus aureus. Optimisation of MR-CS-LPs was conducted using the response surface methodology, and extensive characterization was performed. The anti-bacterial activity of MR-CS-LPs was assessed by determining the minimum inhibitory concentration (MIC) and conducting growth curve analyses. The effects of MR-CS-LPs on S. aureus cell wall and membrane integrity were investigated using techniques such as scanning electron microscopy and physical and chemical analyses. Apoptotic effects were evaluated by examining oxidative stress parameters, and the impact on S. aureus biofilm formation was explored. An LC–MS/MS analysis provided insights into the inhibitory mechanism of MR-CS-LPs against S. aureus. The results indicated that MR-CS-LPs achieved an encapsulation rate of 69.02 %. Furthermore, they demonstrated potent anti-bacterial activity against S. aureus, with an MIC of 0.125 mg/mL. MR-CS-LPs disrupted cell wall and membrane integrity, resulting in macromolecule leakage, induced oxidative stress–mediated apoptosis and effectively suppressed biofilm formation, ultimately leading to bacterial death. Metabolomics analysis revealed that MR-CS-LPs inhibit S. aureus by regulating pyruvate pathways. These findings affirm that MR-CS-LPs possess significant anti-microbial properties, underscoring their potential as effective anti-microbial agents against S. aureus.

Optimization of Cell Membrane Purification for the Preparation and Characterization of Cell Membrane Liposomes.

Cell membrane nanoparticles have attracted increasing interest in nanomedicine because they allow to exploit the complexity of cell membrane interactions for drug delivery. Several methods are used to obtain plasma membrane to generate cell membrane nanoparticles. Here, an optimized method combining nitrogen cavitation in isotonic buffer and sucrose gradient fractionation is presented. The method allows to obtain cell membrane fractions of high purity from both suspension and adherent cells. Comparison with other common methods for membrane extraction, where mechanical lysis using cell homogenizers is performed in isotonic or hypotonic buffers, shows that the optimized procedure yields high purity membrane in a robust and reproducible way. Procedures to mix the purified membrane with synthetic lipids to obtain cell membrane liposomes (CMLs) are presented and indications on how to optimize these steps are provided. CMLs made using crude membrane isolates or the purified membrane fractions show different uptake by cells. The CMLs made with the optimized procedure and liposomes of the same composition but without cell membrane components are thoroughly characterized and compared for their size, zeta potential, bilayer and mechanical properties to confirm membrane protein inclusion in the CMLs. Cell uptake studies confirm that the inclusion of membrane components modifies liposome interactions with cells.

Cholesteryl Phenolipids as Potential Biomembrane Antioxidants

The lipophilization of polyphenols (phenolipids) may increase their affinity for membranes, leading to better antioxidant protection. Cholesteryl esters of caffeic, dihydrocaffeic, homoprotocatechuic and protocatechuic acids were synthetized in a one-step procedure with good to excellent yields of ~50–95%. After evaluation of their radical scavenging capacity by the DPPH method and establishing the anodic peak potential by cyclic voltammetry, their antioxidant capacity against AAPH-induced oxidative stress in soybean PC liposomes was determined. Their interaction with the liposomal membrane was studied with the aid of three fluorescence probes located at different depths in the membrane. The cholesteryl esters showed a better or similar radical scavenging capacity to that of α-tocopherol and a lower anodic peak potential than the corresponding parental phenolic acids. Cholesteryl esters were able to protect liposomes to a similar or greater extent than α-tocopherol. However, despite their antiradical capacity and being able to penetrate and orientate in the membrane in a parallel position to phospholipids, the antioxidant efficiency of cholesteryl esters was deeply dependent on the phenolipid polyphenolic moiety structure. When incorporated during liposome preparation, cholesteryl protocatechuate and caffeate showed more than double the activity of α-tocopherol. Thus, cholesteryl phenolipids may protect biomembranes against oxidative stress to a greater extent than α-tocopherol.

Immune Implications of Cholesterol-Containing Lipid Nanoparticles.

The majority of clinically approved nanoparticle-mediated therapeutics are lipid nanoparticles (LNPs), and most of these LNPs are liposomes containing cholesterol. LNP formulations significantly alter the drug pharmacokinetics (PK) due to the propensity of nanoparticles for uptake by macrophages. In addition to readily engulfing LNPs, the high expression of cholesterol hydroxylases and reactive oxygen species (ROS) in macrophages suggests that they will readily produce oxysterols from LNP-associated cholesterol. Oxysterols are a heterogeneous group of cholesterol oxidation products that have potent immune modulatory effects. Oxysterols are implicated in the pathogenesis of atherosclerosis and certain malignancies; they have also been found in commercial liposome preparations. Yet, the in vivo metabolic fate of LNP-associated cholesterol remains unclear. We review herein the mechanisms of cellular uptake, trafficking, metabolism, and immune modulation of endogenous nanometer-sized cholesterol particles (i.e., lipoproteins) that are also relevant for cholesterol-containing nanoparticles. We believe that it would be imperative to better understand the in vivo metabolic fate of LNP-associated cholesterol and the immune implications for LNP-therapeutics. We highlight critical knowledge gaps that we believe need to be addressed in order to develop safer and more efficacious lipid nanoparticle delivery systems.

An Extensive Review on Novel Liposomes : Classification, Methodology, Characterization, Current Formulations.

Liposomes are vesicles consisting of a phospholipid, hydrophobic drug, hydrophobic tail, hydrophilic tail, cholesterol, targeting agents, positive and negatively charged lipids, and a drug encapsulated in the center of the phospholipid group having a spherical shape. The phospholipid consists of an equal number of aqueous membranes, making the liposomes an important nanocarrier for the drug delivery to the targeted site. Various liposome-based products have recently been approved and are in clinical trials. This review will discuss the structure, classification, types, and method of liposome preparation and various marketed liposomal products.

Preparation of Baicalin Liposomes Using Microfluidic Technology and Evaluation of Their Antitumor Activity by a Zebrafish Model.

Baicalin (BCL), a well-known flavonoid molecule, has numerous therapeutic applications. However, its low water solubility and bioavailability limit its applicability. Microfluidics is a new method for liposome preparation that provides efficient and rapid control of the process, improving the stability and controllability. This study used microfluidic techniques to create baicalin liposomes (BCL-LPs), first screening for optimal total flow rates (TFR) and flow rate ratios (FRR), and then optimizing the phospholipid concentration, phospholipid-to-cholesterol ratio, and Tween-80 concentration using univariate and response surface methodology approaches. The study found that the ideal phospholipid content was 9.5%, the phospholipid-to-cholesterol ratio was 9:1 (w:w), and the Tween-80 concentration was 15%. BCL-LPs achieved 95.323% ± 0.481% encapsulation efficiency under the optimum circumstances. Characterization indicated that the BCL-LPs were spherical and uniform in size, with a mean diameter of 62.32 nm ± 0.42, a polydispersity index of 0.092 ± 0.009, and a zeta potential of -25.000 mV ± 0.216. In vitro experiments found that BCL-LPs had a better slow-release effect and stability than the BCL monomer. In zebrafish bioassays, BCL-LPs performed better than BCL monomer in terms of biological activity and bioavailability. The established method provided a feasible medicine delivery platform for BCL and could apply for the transport and encapsulation of more natural compounds, expanding the applications of drug delivery systems in healthcare and cancer therapies.

Liposome preparation of alpha-arbutin: stability and toxicity assessment using mouse B16F10 melanoma cells

ABSTRACT Melanoma is the most aggressive type of skin cancer, with few therapeutic alternatives following metastasis development. In recent years, drug delivery-associated nanotechnology has shown promising targeted results with diminished adverse effects compared to conventional treatments. This study aimed to (1) examine the effects of plant-derived α-arbutin, a natural compound and (2) compare these findings with bioactively developed liposomes containing α-arbutin utilizing the B16-F10 murine melanoma cell line as a model. Liposomes were obtained through reversed-phase evaporation by applying a spray dryer to assess their stability. The following biologic assays were measured cytotoxicity/antiproliferative (MTT, Neutral Red, and dsDNA PicoGreen). In addition, the levels of melanin and purinergic enzymes were also measured. The production of reactive oxygen species (ROS) and nitric oxide (NO) was determined as a measure of oxidative state. Treatment with nano-liposome containing alpha-arbutin induced a significant 68.4% cytotoxicity, similar to the positive control, in the B16-F10 murine melanoma cell line at 72 hr. Further, arbutin and liposomes containing alpha-arbutin increased levels of ROS and nitrite formation at 72 hr at the highest concentration (100 and 300 µg/ml) of treatments. Arbutin and liposomes containing alpha-arbutin reduced melanin levels at all tested concentrations. In addition, arbutin and alpha-arbutin containing liposomes lowered nucleotides (AMP, ADP, and ATP) and nucleoside (adenosine) levels in melanoma cells. Evidence suggests that α-arbutin containing liposome can be considered as an alternative immunosuppressive agent stimulated in melanoma treatment.

Preparation and characterization of astaxanthin-loaded liposomes by phytosterol oleate instead of cholesterol

Hydrophobic bioactive compounds like astaxanthin (AST) exhibit poor water solubility and low bioavailability. Liposomes, which serve as nanocarriers, are known for their excellent biocompatibility and minimal immunogenicity. Traditionally, liposomes have been primarily constructed using phospholipids and cholesterol. However, the intake of cholesterol may pose a risk to human health. Phytosterol ester was reported to reduce level of cholesterol and improve properties of liposomes. In this study, phytosterol oleate was used to prepare liposomes instead of cholesterol to deliver AST (AST-P-Lip). The size range of AST-P-Lip was 100–220 nm, and the morphology was complete and uniform. In vitro studies showed that AST-P-Lip significantly enhanced the antioxidant activity and oral bioavailability of AST. During simulated digestion, AST-P-Lip protected AST from damage by gastric and intestinal digestive fluid. Additionally, AST-P-Lip had a good storage stability and safety. These results provide references for the preparation of novel liposomes and the delivery of bioactive compounds.

Lipid loss and compositional change during preparation of simple two-component liposomes

Liposomes are used as model membranes in many scientific fields. Various methods exist to prepare liposomes, but common procedures include thin-film hydration followed by extrusion, freeze-thaw, and/or sonication. These procedures can produce liposomes at specific concentrations and lipid compositions, and researchers often assume that the concentration and composition of their liposomes are similar or identical to what would be expected if no lipid loss occurred. However, lipid loss and concomitant biasing of lipid composition can in principle occur at any preparation step due to nonideal mixing, lipid-surface interactions, etc. Here, we report a straightforward HPLC-ELSD method to quantify the lipid concentration and composition of liposomes and apply that method to study the preparation of simple cholesterol/POPC liposomes. We examine common liposome preparation steps, including vortexing during resuspension, lipid film hydration, extrusion, freeze-thaw, and sonication. We found that the resuspension step can play an outsized role in determining the lipid loss (up to ∼50% under seemingly rigorous procedures). The extrusion step yielded smaller lipid losses (∼10–20%). Freeze-thaw and sonication could both be employed to improve lipid yields. Hydration times up to 60 min and increasing cholesterol concentrations up to 50 mol % had little influence on lipid recovery. Fortunately, even conditions with large lipid loss did not substantially influence the target membrane composition, as long as the lipid mixture was below the cholesterol solubility limit. From our results, we identify best practices for producing maximum levels of lipid recovery and minimal changes to lipid composition during liposome preparation for cholesterol/POPC liposomes.

Strategic Developments in Polymer-Functionalized Liposomes for Targeted Colon Cancer Therapy: An Updated Review of Clinical Trial Data and Future Horizons.

Liposomes, made up of phospholipid bilayers, are efficient nanocarriers for drug delivery because they can encapsulate both hydrophilic and lipophilic drugs. Conventional cancer treatments sometimes involve considerable toxicities and adverse drug reactions (ADRs), which limits their clinical value. Despite liposomes' promise in addressing these concerns, clinical trials have revealed significant limitations, including stability, targeted distribution, and scaling challenges. Recent clinical trials have focused on enhancing liposome formulations to increase therapeutic efficacy while minimizing negative effects. Notably, the approval of liposomal medications like Doxil demonstrates their potential in cancer treatment. However, the intricacy of liposome preparation and the requirement for comprehensive regulatory approval remain substantial impediments. Current clinical trial updates show continued efforts to improve liposome stability, targeting mechanisms, and payload capacity in order to address these issues. The future of liposomal drug delivery in cancer therapy depends on addressing these challenges in order to provide patients with more effective and safer treatment alternatives.

Micro-scale quantitative analysis of sterol content in liposomes

The high complexity of biological membranes has driven the development and application of a wide range of model membrane systems. Among these models, liposomes are extensively used because of their versatility in mimicking cellular membranes with a wide range of lipid compositions. However, the accurate quantification of lipid components, such as sterols, within these models remains a critical requirement for validation, data interpretation, and comparison. Here, we present a reliable and sensitive colorimetric assay using the Zak color reaction, which we have specifically adapted for the quantification of sterols at the micro-scale level. The assay was evaluated using cholesterol, ergosterol, and sitosterol standards, reflecting the diversity of sterol species across organisms. The reaction mechanism involves the dehydration of sterols to form carbonium ions, which are oxidized to form various enylic carbonium ions with specific absorption peaks. Due to the different chemical structures of cholesterol, ergosterol, and sitosterol, the resulting spectra show that the colored reaction products are formed in different proportions. The stability and interconversion of these species over time were analyzed. Cholesterol and sitosterol showed a clear peak at 555 nm, while ergosterol had prominent peaks at shorter wavelengths. Sterol assays on liposomal preparations showed accurate sterol incorporation with minimal loss during processing steps. These results demonstrate that this assay provides a robust and accurate measurement of sterol content in large unilamellar vesicles, making it a valuable tool for liposomal studies.

Extraction of Astaxanthin from Haematococcus pluvialis and Preparation of Astaxanthin Liposomes.

Astaxanthin has 550 times more antioxidant activity than vitamin E, so it can scavenge free radicals in vivo and improve body immunity. However, the poor stability of astaxanthin becomes a bottleneck problem that limits its application. Herein, Haematococcus pluvialis (H. pluvialis) as a raw material was used to extract astaxanthin, and the optimal extraction conditions included the extraction solvent (EA:EtOH = 1:6, v/v), extraction temperature (60 °C), and extraction time (70 min). The extracted astaxanthin was then loaded using lecithin to form corresponding liposomes via the ethanol injection method. The results showed that the particle size and zeta potential of the prepared liposomes were 105.8 ± 1.2 nm and -38.0 ± 1.7 mV, respectively, and the encapsulation efficiency of astaxanthin in liposomes was 88.83%. More importantly, the stability of astaxanthin was significantly improved after being embedded in the prepared liposomes.

Fabrication and characterization of hydroquinone in liposomal gel for transdermal drug delivery

This study aimed to formulate a gel for hydroquinone dermal therapy using liposomes to maintain the active agents' concentration in the skin's deepest layers. Cholesterol was incorporated to enhance the liposome's bilayer characteristics, increasing microviscosity, membrane stability, and blister rigidity. Various methods for liposome preparation exist, but the film hydration method, being the most common, was utilized here. Results for formulation HL6, which had lower levels of Lecithin Cholesterol and rotation speed, revealed a vesicle size of 180.4 nm, a Zeta potential of -37.5 mV, and an entrapment efficiency of 69.10±1.52%. In-vitro drug release data for formulations F1, F2, and F3 within 30 minutes showed hydroquinone release rates of 97.75±0.28%, 98.92±0.56%, and 94.45±0.36%, respectively. The order of drug release was F2 > F1 > F3, with F2 demonstrating the maximum release rate. The study concludes that liposomal gel is an effective transdermal drug delivery system for therapeutic molecules. Lipid vesicles, such as liposomes, are among the best mechanisms for delivering medications to their intended locations while minimizing their dissemination to non-target tissues. This liposomal gel-based formulation shows significant potential for effectively treating acne by maintaining high concentrations of active agents in the skin's deepest layers and ensuring a controlled and sustained drug release.

Polymeric liposomes of emtricitabine employing modified pullulan—an attempt to reduce associated hepatotoxicity

Emtricitabine (FTC) a BCS class I drug, is used for HIV prevention. The high solubility of the drug is the leading cause of severe hepatotoxicity and lactic acidosis. This research focuses on the use of modified pullulan for the preparation of polymeric liposomes of FTC. Modified pullulan was synthesized using cholesterol, and succinic anhydride in a controlled chemical environment. The formation of the polymer was established through analysis of spectra. Varying the drug-polymer ratio (1:1, 1:2, and 1:3), the drug-polymer composite was loaded in the vesicular system of soya phosphatidylcholine and cholesterol. Formulations were evaluated for drug entrapment, particle size, surface morphology, and in vitro and ex vivo drug release. An in vivo study of the pure drug and the best formulation on mice was conducted for 28 days following daily oral administration to evaluate the effect on liver and hematological parameters. The best formulation was further subjected to cytotoxicity study on hepatic cell lines. Spectral analysis confirmed the formation of modified pullulan. All formulations showed high drug entrapment in the nanovesicles. The in vitro and ex vivo drug release profiles depicted a controlled release of the drug. Hematological parameters were found to be under control in the animals throughout the experimentation. A comparative histopathology study on the livers and cytotoxicity study on hepatic cell lines revealed the safety of the best formulation over the pure drug. Hence it can be concluded that polymeric liposomes of FTC can be a promising mode of delivery to overcome its limitations.

Resveratrol liposomes in buccal formulations, an approach to overcome drawbacks limiting the application of the phytoactive molecule for chemoprevention and treatment of oral cancer

Resveratrol is currently considered for chemoprevention and treatment of oral cancer, but unfavorable properties of this molecule hinder its clinical use. The present study deals with preparation of resveratrol liposomes by a method that preserves stability and provides payload high enough for chemoprevention and/or treatment of oral cancer. Different temperatures, resveratrol concentrations and molar fractions, as well as the presence or absence of vitamin C in the hydration media were assayed. Liposome hydrodynamic diameter, polydispersity and zeta potential were evaluated by dynamic light scattering. In vitro cytotoxicity, antioxidant activity, and permeability were evaluated using TR146 cells and PermeaPad® membranes. Liposomes were included in hydrogels and films, and their suitability for buccal application was evaluated by in vitro assays. A temperature of 37 °C was optimal to efficiently produce resveratrol liposomes. Vitamin C was found to influence liposome size, while resveratrol concentration significantly influenced entrapment efficiency. Cytotoxicity assay showed high biocompatibility while potent antioxidant activity, the inclusion of vitamin C reinforcing the latter effect. High permeation across membranes and efficient uptake by cells was proved for resveratrol liposomes. Liposomal hydrogels and films were obtained with payload high enough to produce mucosa concentrations above resveratrol IC50 values reported for cancer cells.