Encapsulation Efficiency Of Liposomes Research Articles

Three Diterpene Lactones from Andrographis paniculata (Burm. f) Nees In vitro, In silico Assessment of the Anticancer and Novel Liposomal Encapsulation Efficiency

: Three compounds from Andrographis paniculata (Burm. f) Nees leaf were isolated and identified using 1H, 13C, 2D-NMR, and HR-MS techniques for the first time. Compound 3,19-Di-O-acetylandrographolide (3,19-DAA) or (4) is produced by acetylating compound (2). Compounds (2) and (4) have been investigated for their cytotoxic effects on three human cancer cell lines (SK-LU-1, Hela, and HepG2) using the MTT method. Compound (4) demonstrated significant cytotoxicity against all three cancer cell lines, with IC50 values ranging from 8.38 to 10.15 μM. This represents an increase in cytotoxicity of 2.67 to 3.12-fold compared to compound (2). One way to deal with the problem of low water solubility is by encapsulating (4) into liposomes using a thin-film hydration technique. The optimal conditions for maximizing encapsulation efficiency involve molar ratios of phosphatidylcholine, 3,19-DAA, and cholesterol at 4:1:1. Encapsulating compound (4) within nanoscale liposomes increases its water solubility compared to the free form of compound (4). Pose 324 of compound (4) demonstrated the best conformation among 500 docking conformations when docked to enzyme 1T8I in a in silico docking study. The free Gibbs energy and inhibition constant were determined to be -7.09 Kcal/mol and 6.32 μM, respectively. These values help elucidate the strong interaction between compound (4) and the enzyme in the ligand interaction model. The molecular dynamics simulation using Desmond software in the Linux environment was conducted for a duration of 0 to 100 nanoseconds on the complex formed by pose 324 and 1T8I. The results showed effective interactions within the complex, with stability observed from 0 to 60 nanoseconds. Throughout the simulation, specific amino acids such as Ala 499 (involved in 90% of the simulation time with hydrogen bonding via a water bridge) and Thr 501 (involved in 50% of the simulation time with one hydrogen bond via a water bridge) were found to play significant roles. The majority of torsion bondings are C-O bondings in the acetyl group of compound (4), with torsion energy values of 13.47 Kcal/mol. Carbon atom C-29 at position 324 exhibits the highest fluctuation.

Production of liposomes by microfluidics: The impact of post-manufacturing dilution on drug encapsulation and lipid loss

Microfluidic mixing is recognized as a convenient method to produce liposomes for its scalability and reproducibility. Numerous studies have described the effect of process parameters such as flow rate ratios and total flow rate on size and size distribution of vesicles. In this work, we focused our attention on the effect of flow rate ratios on the encapsulation efficiency of liposomes, as we hypothesized that different amount of residual organic solvent could affect the retention of lipophilic drug molecules within the bilayer. In a further step, we investigated how the liposomes integrity and loading were impacted by different methods of solvent removal: direct dialysis and dilution & dialysis. Liposomes were prepared by rapidly mixing an ethanolic solution of lipids and a model drug with buffer in a herringbone micromixer, employing four different flow rate ratios (FRR, 4:1, 7:3, 3:2, 1:1). Quercetin, resveratrol and ascorbyl palmitate were used as model antioxidant drugs with different lipophilicity. Data showed that liposomes produced using lower flow rate ratios (i.e., with more residual ethanol) had lower encapsulation efficiencies as well as a more prominent loss of lipids from the bilayer following purification with direct dialysis. If the amount of residual ethanol was reduced to 5% (dilution & dialysis method), the lipids and drug leakage was prevented. Such effect was correlated with the drug aggregation propensity in different ethanol/water mixtures measured by molecular dynamics simulations. Overall, these results highlight the need to tailor the purification method basing on the molecular properties of the loaded drug to ensure high encapsulation and limit the waste of material.

Liposomes delivery systems of functional substances for precision nutrition.

Natural bioactive compounds with antioxidant, antimicrobial, anticancer, and other biological activities are vital for maintaining the body's physiological functions and enhancing immunity. These compounds have great potential as nutritional therapeutic agents, but they can be limited due to their poor flavor, color, unstable nature, and poor water solubility, and degradation by gastrointestinal enzymes. Liposomes, as ideal carriers, can encapsulate both water-soluble and fat-soluble nutrients, enhance the bioavailability of functional substances, promote the biological activity of functional substances, and control the release of nutrients. Despite their potential, liposomes still face obstacles in nutrient delivery. Therefore, the design of liposomes for special needs, optimization of the liposome preparation process, enhancement of liposome encapsulation efficiency, and industrial production are key issues that must be addressed in order to develop food-grade liposomes. Moreover, the research on surface-targeted modification and surface functionalization of liposomes is valuable for expanding the scope of application of liposomes and achieving the release of functional substances from liposomes at the appropriate time and site. The establishment of in vivo and in vitro digestion models of nutrient-loaded liposomes, in-depth study of gastrointestinal digestive behavior after liposome ingestion, targeted nutrient release, and deciphering the nutritional intervention of human diseases and positive health promotion are promising fields with broad development prospects.

Transforming a Toxic Non-Ionizable Drug into an Efficacious Liposome via Ionizable Prodrug and Remote Loading Strategies against Malignant Breast Tumors.

Liposomes (lipos), one of the most successful nanotherapeutics in the clinic, have made a rapid advance over the past few years. However, still, several challenges exist for lipos for clinical practice, such as low drug loading and premature drug leakage during in vivo circulation. Paclitaxel (PTX), a commonly used first-line drug for cancer chemotherapy, was chosen as the model drug. Due to its non-ionizable and water-insoluble characteristics, the drug-loading efficiency of the marketable PTX lipos, Lipusu, is only 6.76%. Herein, we designed an ionizable PTX prodrug (PTXP) by modifying phenylboronic acid on the C2' hydroxyl group of PTX for the remote loading of liposomal formulations through the pH gradient method. Compared with Lipusu, PTXP lipos displayed a 34% higher loading efficiency and an encapsulation efficiency of approximately 95%. A series of in vitro/vivo experiments indicated that PTXP lipos possess colloidal stability, prolonged blood circulation, high tumor site accumulation, potent anti-tumor effects, and safety. A combination of ionizable prodrugs and remote loading has proved to be an effective and simple strategy to achieve high liposomal encapsulation efficiency of poorly soluble non-ionizable drugs for clinical application.

Preparation and Physical Characterization of DNA Binding Cationic Liposomes.

Cationic liposomes are routinely employed as one of the major nonviral transfecting agents for intracellular delivery of hydrophilic molecules such as nucleic acids, peptides, and proteins. Cationic liposomes when complexed with DNA form a strong positively charged cationic liposome-DNA complex or lipoplex. The chapter discusses, primarily, the major preparation technique for cationic liposomes and its physical characterization, with a focus on SYBR Green I dye exclusion assay and DNA encapsulation enhancement by freeze-thaw technique. SYBR Green I dye exclusion assay is a technique to determine the total amount of liposomal lipids required to bind a unit weight of DNA, which is critical for transfection experiments. Freeze-thaw technique on the other hand is one of the major techniques to improve DNA encapsulation efficiency in liposomes.

Encapsulation efficiency and oral delivery stability of chitosan–liposome‐encapsulated immunoglobulin Y

The degradation of acidic gastric juice on immunoglobulin Y (IgY) leads to destruction on the structural and loss of the bioactivity, limiting the bioavailability of oral IgY and its research or application in adjuvant treatment of diseases. In this work, it was surmounted with IgY-loaded chitosan-liposomes prepared by supercritical carbon dioxide-assisted method. A range of chitosan concentrations (0%, 0.5%, 0.8%, 1.1%, and 1.4%) were selected to explore the influence of chitosan concentration on the encapsulation effectiveness, stability, and in vitro-simulated digestive release properties of liposome-encapsulated IgY. The results displayed that owing to the robust interaction between chitosan and liposomes, the particle size, encapsulation efficiency, and stability of liposomes reached the optimal state at a chitosan concentration of 0.8%, with the encapsulation efficiency reaching 77.51%. Moreover, the liposomes could be stored at 4°C for 9 days without obvious sedimentation. The zeta potential of liposomes containing 0.8% chitosan was higher than that of samples without chitosan at high salt concentration treatment. In vitro release experiments demonstrated that liposomes fitted well in the Peppas equation. Chitosan-coated liposomes were capable of delaying the release of IgY in the stomach during simulated digestion, allowing more IgY to be released in the intestine. To sum up, Chitosan played a vital role in maintaining the stability and encapsulation of IgY, and the results of this work provide a theoretical basis for the development and utilization of chitosan and the protection of activity of IgY when administered orally. PRACTICAL APPLICATION: IgY serves as a bioactive substance with anti-inflammatory, antibacterial, and antioxidant functions. However, it is far from satisfactory for the oral delivery activity of IgY. Encapsulation of liposomes contributed to alleviate the release of IgY in the stomach. However, liposomes were less stable and not efficient enough to encapsulate IgY. This study demonstrated that the addition of 0.8% chitosan could effectively enhance the encapsulation efficiency of liposomes and improved the stability of liposomes. It might contribute to the solution of the oral delivery activity of IgY and provide a promising idea for the utilization of chitosan.

Study on the Preparation and Characterization of Glycyrrhizic Acid Liposomes

The purpose of this study was to prepare glycyrrhizic acid nanoliposomes and evaluate the encapsulation efficiency and other properties of glycyrrhizic acid nanoliposomes, which would provide a reference for further research on Glycyrrhizic Acid in the treatment of liver diseases. Firstly, the preparation conditions of glycyrrhizic acid liposomes were optimized by the orthogonal design method. Then, glycyrrhizic acid liposomes were prepared by ultrasonic-film dispersion method and the encapsulation efficiency was determined by the HPLC method. Finally, the properties of glycyrrhizic acid nanoliposomes were also studied. The results showed that the optimal preparation conditions of liposomes were as follows: the ratio of drug to lipid was 1:30; Lecithin: cholesterol = 1:1; Hydration medium: pure water; Ultrasonic time: 120 s. The encapsulation efficiency of liposomes was about 90%. The final liposomes were round and uniform in distribution, with an average particle size of about 50 nm and absolute zeta potential of −28.9 mV. In this study, glycyrrhizic acid liposomes were prepared and the optimal preparation conditions were optimized. The encapsulation efficiency of the liposomes under the optimized conditions was determined. The evaluation of the morphology, size, particle size and stability of the liposomes was completed.

Fast and versatile analysis of liposome encapsulation efficiency by nanoParticle exclusion chromatography

Liposomes are an attractive drug delivery platform for a wide variety of pharmaceutical molecules. Encapsulation efficiency, which refers to the amount of drug contained inside liposomes compared with the total amount of drug, is a critical quality attribute of liposome products, as the free drug in a liposomal formulation may cause toxicity or undesired biodistribution. The determination of encapsulation efficiency requires the measurement of at least two of the three drug populations: total drug, encapsulated drug and free drug. However, direct measurement of the encapsulated drug and free drug remains a challenging analytical task. Nanoparticle exclusion chromatography (nPEC), an emerging high-performance liquid chromatography (HPLC) technique, has shown great potential in separating and quantifying the free drug in liposomal formulations. In this study, nPEC was systematically evaluated for two representative liposomal formulations containing either hydrophilic or hydrophobic small molecule drugs. It is reported for the first time that the insoluble free drug suspended in the aqueous formulation can be directly measured by nPEC. This free drug in the suspension sample was quantified with excellent accuracy and precision. On the other hand, the total drug measurement from dissociated liposomes was confirmed by the benchmark methodology of reversed phase liquid chromatography (RPLC). The facile quantitation of free and total drug in the liposome formulation enables the fast and accurate determination of the encapsulation efficiency, which can be used to guide the formulation development and characterize the product quality.

Liposomes Loaded with Unsaponifiable Matter from Amaranthus hypochondriacus as a Source of Squalene and Carrying Soybean Lunasin Inhibited Melanoma Cells.

Amaranthus hypochondriacus is a source of molecules with reported health benefits such as antioxidant activity and cancer prevention. The objective of this research was to optimize the conditions for preparing a liposome formulation using amaranth unsaponifiable matter as a source of squalene in order to minimize the particle size and to maximize the encapsulation efficiency of liposomes for carrying and delivering soybean lunasin into melanoma cell lines. Amaranth oil was extracted using supercritical dioxide carbon extraction (55.2 MPa pressure, 80 °C temperature, solvent (CO2)-to-feed (oil) ratio of 20). The extracted oil from amaranth was used to obtain the unsaponifiable enriched content of squalene, which was incorporated into liposomes. A Box–Behnken response surface methodology design was used to optimize the liposome formulation containing the unsaponifiable matter, once liposomes were optimized. Soybean lunasin was loaded into the liposomes and tested on A-375 and B16-F10 melanoma cells. The squalene concentration in the extracted oil was 36.64 ± 0.64 g/ 100 g of oil. The particle size in liposomes was between 115.8 and 163.1 nm; the squalene encapsulation efficiency ranged from 33.14% to 76.08%. The optimized liposome formulation contained 15.27 mg of phospholipids and 1.1 mg of unsaponifiable matter. Cell viability was affected by the liposome formulation with a half-maximum inhibitory concentration (IC50) equivalent to 225 μM in B16-F10 and 215 μM in A-375. The liposomes formulated with lunasin achieved 82.14 ± 3.34% lunasin encapsulation efficiency and improved efficacy by decreasing lunasin IC50 by 31.81% in B16-F10 and by 41.89% in A-375 compared with unencapsulated lunasin.

A study on chitosan-coated liposomes as a carrier of bovine serum albumin as oral protein drug

The development of protein drug liposomes was limited due to the instability of the structure of liposomes, such as easy aggregation, easy fusion, and drug leakage. The object of this work was to prepare bovine serum albumin (BSA) loaded liposomes (BSA-Lip) using BSA as a protein model drug and then BSA-Lip was further coated with chitosan (CH-BSA-Lip) in order to improve the stability of phospholipid bilayer membrane. It was found that the particle size of BSA-Lip increased after being coated with chitosan and the surface potential changed from negative charge to positive charge due to the electrostatic interaction between liposomes and chitosan. After chitosan coating, the encapsulation efficiency of liposomes also increased due to the interaction between positively charged chitosan and negatively charged BSA. Fourier transform infrared spectroscopy analysis confirmed that BSA was encapsulated into liposomes and chitosan was successfully coated on the surface of liposomes. Transmission electron microscopy showed that the particles were nanosized and spherical. The physical stability and in vitro digestion stability of liposomes were examined by observing the changes of particle size and potential. It was found that chitosan coating enhanced the stability of liposomes significantly. The in vitro release profile of CH-BSA-Lip possessed a slow release behavior, and BSA release was governed by both diffusion and dissolution from phospholipid bilayer.

Spontaneous In Situ Formation of Liposomes from Inert Porous Microparticles for Oral Drug Delivery.

Despite the wide-spread use of liposomal drug delivery systems, application of these systems for oral purposes is limited due to their large-scale formulation and storage issues. Proliposomes are one of the formulation approaches for achieving solid powders that readily form liposomes upon hydration. In this work, we investigated a dry powder formulation of a model low-soluble drug with phospholipids loaded in porous functionalized calcium carbonate microparticles. We characterized the liposome formation under conditions that mimic the different gastrointestinal stages and studied the factors that influence the dissolution rate of the model drug. The liposomes that formed upon direct contact with the simulated gastric environment had a capacity to directly encapsulate 25% of the drug in situ. The emerged liposomes allowed complete dissolution of the drug within 15 min. We identified a negative correlation between the phospholipid content and the rate of water uptake. This correlation corroborated the results obtained for the rate of dissolution and liposome encapsulation efficiency. This approach allows for the development of solid proliposomal dosage formulations, which can be scaled up with regular processes.

Niosomes and liposomes as promising carriers for dermal delivery of Annona squamosa extract

The leaf extract of Annona squamosa L. has antibacterial, antidiabetic, antioxidant, and anticancerous activities. The present work aims to compare between liposomes and niosomes as carriers for A. squamosa extract to improve its transdermal bioavailability. Physical characterization for niosomes and liposomes was performed using: transmission electron microscope (TEM), scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). In addition, the encapsulation efficiency for A. squamosa in both carriers was evaluated and in-vitro drug release experiments were performed. The results proved the potential of both carriers to penetrate the outer layer of the skin (stratum corneum) which is considered as a strong barrier against the diffusion of many compounds through the skin. Moreover, the results pointed out that niosomes and liposomes lasted long time through the skin, which ensures the presence of antioxidant extract in the skin for prolonged periods. This would have a benefit of targeting free radicals in the skin. The encapsulation efficiency of liposomes for A. squamosa extract exceeded that of niosomes, however, niosomes demonstrated longer time of drug release through the skin. In conclusion, niosomes and liposomes are promising carriers for dermal delivery of the antioxidant extract Annona squamosa.

Liposomal Nanovesicles for Efficient Encapsulation of Staphylococcal Antibiotics.

Liposomes are attractive vehicles for localized delivery of antibiotics. There exists, however, a gap in knowledge when it comes to achieving high liposomal loading efficiencies for antibiotics. To address this issue, we investigated three antibiotics of clinical relevance against staphylococcal infections with different hydrophilicity and chemical structure, namely, vancomycin hydrochloride, teicoplanin, and rifampin. We categorized the suitability of different encapsulation techniques on the basis of encapsulation efficiency, lipid requirement (important for avoiding lipid toxicity), and mass yield (percentage of mass retained during the preparation process). The moderately hydrophobic (teicoplanin) and highly hydrophobic (rifampin) antibiotics varied significantly in their encapsulation load (max 23.4 and 15.5%, respectively) and mass yield (max 74.1 and 71.8%, respectively), favoring techniques that maximized partition between the aqueous core and the lipid bilayer or those that produce oligolamellar vesicles, whereas vancomycin hydrochloride, a highly hydrophilic molecule, showed little preference to any of the protocols. In addition, we report significant bias introduced by the choice of analytical method adopted to quantify the encapsulation efficiency (underestimation of up to 24% or overestimation by up to 57.9% for vancomycin and underestimation of up to 61.1% for rifampin) and further propose ultrafiltration and bursting by methanol as the method with minimal bias for quantification of encapsulation efficiency in liposomes. The knowledge generated in this work provides critical insight into the more practical, albeit less investigated, aspects of designing vesicles for localized antibiotic delivery and can be extended to other nanovehicles that may suffer from the same biases in analytical protocols.

Preparation and evaluation of four kinds of mixed essential oil liposomes in Jieyu Anshen Formula

In order to increase the stability and solubility of essential oil in Jieyu Anshen Formula, this study was to prepare the essential oil into liposomes. In this experiment, the method for the determination of encapsulation efficiency of liposomes was established by ultraviolet spectrophotometer and dextran gel column. The encapsulation efficiency and particle size of liposomes were used as evaluation indexes for single factor investigation and Box-Behnken design-response surface method was used to optimize the design. Then the optimal formulation of volatile oil liposome was characterized using methyleugenol, elemin, β-asarone and α-asarone as index components. Finally, the in vitro transdermal properties of liposomes were studied by modified Franz diffusion cell. The results showed that the concentration of lecithin, the mass ratio of lecithin to volatile oil, and the stirring speed were the three most significant factors affecting the liposome preparation. The optimum formulation of volatile oil liposome was as follows: the concentration of lecithin was 7 g·L~(-1); mass ratio of lecithin to volatile oil was 5∶1; and the stirring speed was 330 r·min~(-1). Under such conditions, the prepared liposomes had blue emulsion light, good fluidity, half translucent, with particle size of(102.6±0.35) nm, Zeta potential of(-17.8±0.306) mV, permeability of(1.67±1.01)%, and stable property if liposome was stored at 4 ℃. 24 h after percutaneous administration, the cumulative osmotic capacity per unit time was(30.485 2±1.238 9),(34.794 8±0.928 3),(26.677 1±1.171 7),(3.066 2±0.175 3) μg·cm~(-2)respectively for methyleugenol, elemin, β-asarone and α-asarone. In vitro transdermal behaviors of methyleugenol, elemin, β-asarone and α-asarone in liposomes were all consistent with Higuchi equation. The prepared volatile oil liposomes met the relevant quality requirements, providing a reference for further research on preparation of multi-component Chinese medicine essential oil liposomes.

The activity of encapsulated meglumine antimoniate in stearylamine-bearing liposomes against cutaneous leishmaniasis in BALB/c mice

Topical treatment of cutaneous leishmaniasis has demonstrated appropriate alternative for reducing toxicity of conventional treatments, improving patients' compliance and reducing treatment costs. Furthermore, outbreak of cutaneous leishmaniasis in war and conflict zones emerges finding an effective, economical and user-friendly treatment. In the context of liposomal topical drug delivery, we developed and characterized meglumine antimoniate (MA) loaded liposomes and investigated their effectiveness in topical treatment of cutaneous leishmaniasis. Previously, we showed the promising use of liposomal formulation of MA in treatment of cutaneous leishmaniasis in BALB/c mice. Here, we included Stearylamine (SA) in liposomes’ structure which has antileishmanial activity by itself. . Size and encapsulation efficiency of liposomes were measured and in vitro permeation was performed using mice model. In vitro toxicity of liposomes was measured against leishmania promastigotes and amastigotes. Liposomes were used topically twice a day for 4 weeks to treat leishmania lesions in BALB\\c mice model. In vitro permeation study showed liposomal formulations improved the percent of MA permeation compared with MA-cream. Promastigotes and amastigotes assay results showed significant enhanced toxicity in Liposomal-MA containing SA compared to Lip-MA. In BALB\\c mice model of cutaneous leishmaniasis, liposomal groups exhibited significantly smaller lesion size compared to control groups (p < 0.01). In addition, the spleen parasite burden was significantly (P < 0.01) lower in mice treated with selected liposomal MA than in mice treated with PBS, control liposomes and MA cream. The results of this study showed that SA-liposomes encapsulated with MA might be useful as a candidate for the topical treatment of CL which merit further investigation.

Formation and characterization of spray dried coated and uncoated liposomes with encapsulated black carrot extract

The degradation of black carrot anthocyanins (BCE) under stress conditions as under the effect of a spray drying process was evaluated in different encapsulation systems (extract, chitosan-coated and uncoated liposomes and chitosan-extract-mixture). The encapsulation efficiencies of liposomes prepared by high-pressure homogenization containing 2% lecithin with 0.1%, 0.2%, and 0.4% extract were found as 86.6% ± 16.1%, 82.2% ± 9.7%, and 46.9% ± 6.3%, respectively. The extract-loaded liposomes (0.2% extract) were chosen for liposomes considering further dilutions. The chitosan-coated liposomes were generated with 0.1% chitosan according to their particle size (82.7 ± 1.5 nm) and zeta potential of 51.4 ± 0.6 mV. All samples were found to be physically stable after the spray drying process. In addition, SEM images of the liposomal powder particles showed a uniformly wrinkled surface that would indicate stability of liposomal systems against spray drying. However, the liposomal samples showed lower stability compared to the BCE and BCE-chitosan mixtures according to the biochemical analysis of the reconstituted powders.

Formulation and Efficacy of Liposome-encapsulated Afatinib for Therapy of Non-small Cell Lung Cancer

背景与目的阿法替尼是针对非小细胞肺癌及继发性耐药研发的第二代不可逆表皮生长因子受体抑制剂，目前仅停留在口服给药方式，其生物利用度低，不良反应较多。本研究旨在制备新型药物传递系统-阿法替尼脂质体，并建立包封率的测定方法。方法4种不同方法制备阿法替尼脂质体，通过对比包封率和粒径确定最佳制备工艺。结果经验证可采用葡聚糖凝胶微柱离心法纯化脂质体，并通过紫外分光光度法测定脂质体的包封率。不同制备方法中硫酸铵梯度法制备的脂质体，包封率约为90.73%，平均粒径为108.6 nm。结论硫酸铵梯度法制备阿法替尼脂质体包封率高、粒径小，紫外分光光度法用来测定脂质体的包封率简单易行、准确度高。

Preparation and characterization of norcantharidin liposomes modified with stearyl glycyrrhetinate.

In the current study, norcantharidin (NCTD)-loaded liposomes (LIPs) modified with stearyl glycyrrhetinate (SG; SG-NCTD-LIP) were prepared by the ethanol injection method. To increase the drug encapsulation efficiency (EE), the formulation of NCTD-LIP was optimized by single factor test and orthogonal design. The release of NCTD in vitro from SG-NCTD-LIP was evaluated by equilibrium dialysis. The cytotoxicity of SG-NCTD-LIP in HepG2 was investigated by MTT assay. The results revealed that the EE of liposomes was ~27.80%, the average SG-NCTD-LIP was 87.5 nm, the in vitro NCTD release from SG-NCTD-LIP was delayed compared with NCTD in solution and the drug-release kinetic followed a first-order model. MTT assays revealed increased cytotoxicity activity against HepG2 cells for SG-NCTD-LIP compared with free NCTD. In conclusion, SG-NCTD-LIP prepared in the present study may be a promising liposomal drug delivery system for anticancer drugs in liver-targeting therapy.

Antioxidant property of SiO2-eugenol liposome loaded nanofibrous membranes on beef

Abstract In consideration of the strong volatility and chemical instability of eugenol, liposomes were introduced to remain the activity of eugenol during processing and storage. Silica nanoparticle (SiO 2 ) was used to adsorb eugenol before liposome encapsulation for getting better physicochemical properties and physical stability. The results of particle size, zeta potential and encapsulation efficiency of liposomes containing SiO 2 -eugenol were 315.7 ± 0.7 nm, −47.7 ± 0.3 mV, and 89.91 ± 0.43%, respectively. The experiments testing the physical stability of liposomes containing SiO 2 -eugenol showed that SiO 2 could significantly promote its stability. For the application in food antioxidant, electrospun nanofibrous membranes were introduced to immobilize the SiO 2 -eugenol liposomes. In this study, the antioxidant assay of SiO 2 -eugenol liposome loaded nanofibrous membranes exhibited antioxidant activity on beef.

The effect of superparamagnetic iron oxide nanoparticles surface engineering on relaxivity of magnetoliposome.

The purpose of this work is evaluating the effect of ultra small superparamagnetic iron oxide nanoparticles (USPIONs) coatings on encapsulation efficiency in liposomes and cellular cytotoxicity assay. Moreover, we assessed the effects of surface engineering on the relaxivity of magnetoliposome nanoparticles in order to create a targeted reagent for the intelligent diagnosis of cancers by MRI. For estimating the effect of nanoparticle coatings on encapsulation, several kinds of USPIONs coated by dextran, PEG5000 and citrate were used. All kinds of samples are monodispersed and below 100 ± 10 nm and the coatings of USPIONs have no significant effect on magnetoliposome diameter. The coating of USPIONs could have effect on percentage of encapsulation. The dextran coated USPIONs have more stability and quality accordingly the encapsulation increased up to 92%, then the magnetoliposome nano particles have been targeted by Herceptin and anti-HER2 VHH, separately. Over storage period of four weeks the resulting particles were stable and physico-chemical properties such as size and zetapotential did not show any significant changes. The relaxivity of contrast agents was measured using a 1.5 T MRI. The r2/r1 ratio was more than two for all samples which demonstrate the negative contrast enhancing of all SPION embedded specimens. The high ratio of r2/r1 as well as high r2 is the best combination of a negative contrast agent as it is obtained for pure magnetite. The value of r2/r1 for all other samples including Herceptin targeted magnetoliposome, anti-HER2 VHH targeted magnetoliposome and non-targeted magnetoliposome were between ~21 to ~28, which show the magnetite embedded samples have enough negative contrast to be detectable by MRI. Therefore the HER2 targeted magnetoliposomes are a good and stable candidate as contrast agents in clinical radiology and biomedical research with minimal cytotoxicity and biocompatibility effects. Copyright © 2016 John Wiley & Sons, Ltd.