Determination Of Encapsulation Efficiency Research Articles

Liposomes as a carrier for 4–hydroxycoumarin: characterisation, stability and antioxidant potential

<p>The aims of the present research were to develop and characterize 4-hydroxycoumarin-loaded liposomes <em>via </em>the determination of encapsulation efficiency, antioxidant capacity, vesicle size, polydispersity index (PDI), zeta potential, conductivity, mobility, density, surface tension, viscosity, and 60-day storage stability. The encapsulation efficiency of 4-hydroxycoumarin in liposomal particles was 96.7 ± 1.2%. The ABTS and DPPH radical scavenging capacity of the prepared liposomes was 89.76 ± 0.56% and 93.18 ± 0.23%, respectively, whereas cupric ion-reducing antioxidant capacity amounted to 0.367 ± 0.003 mmol Trolox equivalent (TE)/L. The density of liposomes with 4-hydroxycoumarin was 1.007 ± 0.002 g/cm<sup>3</sup>, surface tension was 22.7 ± 0.2 mN/m, and viscosity was 14.3 ± 0.2 mPa·s. Vesicle size and PDI of 4-hydroxycoumarin-loaded liposomes were changed from 1286.3 ± 73.8 nm to 2077.3 ± 63.2 nm and from 0.409 ± 0.050 to 0.676 ± 0.064, respectively, during the 60-day stability study. The zeta potential of the obtained liposomes was changed from -16.73 ± 0.47 mV to -10.31 ± 0.42 mV, while mobility varied from -1.311 ± 0.036 µmcm/Vs to -0.806 ± 0.031 µmcm/Vs. The conductivity did not change during 60 days and amounted to approximately 0.020 mS/cm. Overall, due to the high encapsulation efficiency and antioxidant capacity, the obtained results qualify liposomes to be used as 4-hydroxycoumarin carriers for future examination of its biological activities and potential application in medicine and pharmaceutical products. However, future experiments should include the optimization of the liposomal composition with the aim of improving 4-hydroxycoumarin-loaded liposome stability.</p>

Lycopene-Loaded Solid Lipid Nanoparticles: Preparation, Characterization, ROS-Scavenging, and In vitro Anti-Melanogenesis Evaluations

Background: Lycopene, a natural antioxidant from carotenoids, is produced by plants and microorganisms. It has been investigated in many studies in relation with potential health effects. Objective: Due to the high lipid-solubility of lycopene, its skin penetration is challenged. Therefore, in the present study, lycopene was loaded into lipid nanoparticles to improve penetration and pharmacological properties. Methods: Solid lipid nanoparticles (SLNs) containing lycopene were prepared and anti-tyrosinase properties were studied in the present study. The formulation was investigated in terms of drug release and antityrosinase properties. Determination of encapsulation efficiency was performed directly. Electron microscopy was used to examine the shape of the nanoparticles. Subsequently, the rate of drug release was investigated by the cell diffusion method. The present study applied cytotoxicity tests, cellular tyrosinase inhibition, melanin content, and free radical level to evaluate the effect of formulations on melanogenesis inhibition, and western blot assay was used to determine tyrosinase and MITF levels. Results: The results from particle size investigation for LYC-SLNs were 151.1 ± 2.3, and exploring the data of electron microscopy showed that the shapes of nanoparticles were spherical, and the encapsulation efficiency was 85.76 ± 2.75%. In determining the anti-tyrosinase effects of LYC-SLNs, a significant reduction in cellular tyrosinase activity and melanin and ROS levels were observed; It is also worth noting that LYC-SLNs reduced melanin production with minimal toxicity against melanoma cells. Conclusion: In general, the results confirm that SLNs can be an efficient delivery platform for the topical delivery of lycopene as a natural anti-oxidant and anti-melanogenic agent.

THE CHARACTERIZATION OF SILYMARIN AND SILIBININ LIPOSOMES

The aim of the present study was the characterization of silymarin and silibinin liposomes via determination of encapsulation efficiency, particle size, polydispersity index (PDI), zeta potential, mobility, and conductivity, as well as storage stability during 28 days at 4ºC and stability after UV irradiation. Encapsulation efficiencies of silymarin and silibinin were 92.05±1.41% and 87.86±2.06%, respectively. Particle size and PDI of the liposomes with silymarin were changed from 3541.3±62.5 nm to 2677.0±44.2 nm and from 0.346±0.044 to 0.228±0.036, respectively, during the 28-day stability study; particle size and PDI of the liposomes with silibinin were changed from 2074.7±19.4 nm to 2704.0±35.0 nm and from 0.328±0.030 to 0.456±0.026, respectively. The Zeta potential of the silymarin-loaded liposomes and silibinin-loaded liposomes was changed from -27.0±0.7 mV to -26.4±0.4 mV and from -29.4±0.6 mV to -29.0±0.4 mV, respectively. Mobility and conductivity of the liposomes with silymarin were changed from -2.120±0.057 μmcm/Vs to - 2.067±0.028 μmcm/Vs and from 0.017±0.005 mS/cm to 0.009±0.004 mS/cm, respectively. Mobility and conductivity of the liposomal particles with silibinin were changed from -2.307±0.053 μmcm/Vs to -2.110±0.033 μmcm/Vs and from 0.018±0.003 mS/cm to 0.060±0.001 mS/cm, respectively. UV irradiation did not affect particle size and PDI of all liposomes, but it caused a decrease in zeta potential: -23.9±0.8 mV for silymarin and -24.5±0.7 mV for silibinin, in mobility: - 1.874±0.064 μmcm/Vs for silymarin and -1.920±0.057 μmcm/Vs for silibinin, and in conductivity: 0.014±0.001 mS/cm for silymarin and 0.007±0.003 mS/cm for silibinin. Overall, the obtained results qualify liposomes to be used as silymarin and silibinin carriers for application in functional foods and pharmaceutical products.

Design, preparation and evaluation of nanoparticles of 5-Flurouracil for the targeted delivery to treat colon cancer

The objective of the study is to prepare the nano particles of 5-fluorouracil with targeted delivery to the colon with enhancement of bioavailability and decrease the side effects of the drug. 5-Fluorouracil-loaded PLGA nanoparticles were developed by double solvent evaporation technique method. Characterization was carried out by determination of encapsulation efficiency (%), loss on Drying. The in-vitro drug release of drug 5- Fluorouracil was carried out for formulations (F1-F4), it is concluded that F4 was the best formulation which shows the most desired rate drug release and concluded that the polymer PLGA have a capacity of protection the drug in the GI and small intestinal Fluid hence, the maximum release of drug in the colonic region of large intestine.

Perbandingan Teknik Aerasi dan Ultrasonikasi Gelasi Ionik Nanopartikel Deksametason Natrium Fosfat

Alginate, a biocompatible and biodegradable natural polymer, has been widely used as a drug molecular carrier using ionic gelation methods (crosslinking). One of the factors that must be taken into account in its preparation is the mechanical effect. The purpose of this study was to explain the preparation process and the characteristics of the calcium alginate crosslinkers as dexamethasone sodium phosphate carriers with low energy and high energy techniques. Nanosuspension is made in six formulas using 3 techniques: low energy (aeration), high energy (ultrasonication), low and high energy (aeration and ultrasonication) with a fixed concentration of dexamethasone sodium phosphate and sodium alginate, that is 0,2% and 0,1%, with 0,02% and 0,2% of calcium chloride. Determination of particle size, zeta potential, and morphology of nanoparticles using Particle Size Analyzer (PSA) and Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM). Determination of encapsulation efficiency using UV/Vis spectrophotometer and statistical analysis using MANOVA test. Synthesis of nanosuspension using a combination of low and high energy (aeration and ultrasonication) results in the most optimal characteristics with particle size value of 352.90 ± 6.10 nm, homogenized polydispersity index (0,52 ± 0,04), optimal potential zeta -44,40 ± 0,4 mV, the encapsulation efficiency of 49,5 - 74,8% and spherical particle shape. It can be concluded that the preparation using a combination of low and high energy is the most optimal preparation result.

Efavirenz-loaded polymeric nanocapsules: Formulation, development, and validation of an RP-UHPLC-DAD method for drug quantification, determination of encapsulation efficiency, stability study, and dissolution profile

Efavirenz-loaded polymeric nanocapsules: Formulation, development, and validation of an RP-UHPLC-DAD method for drug quantification, determination of encapsulation efficiency, stability study, and dissolution profile

Development and validation of the method for determination of encapsulation efficiency of cytochrome c in liposomes

A strategic pathway in creating high-potent medical products is with targeted therapeutic systems that are based on nanoparticles of various structure. Such particles are capable of providing a targeted effect and an increase in bioavailability of the medical products. A special place among modern targeted drug delivery systems is held by liposomal nanoparticles which have apparent advantages over nanoparticles of an another type The problem number one for pharmacy lies in developing specific methods of control of nanosize drug delivery systems.
 This research is dedicated to the development and validation of a technique for determining encapsulation efficiency of cytochrome C in liposomes.
 The subject of research comprised the obtained liposomal form of cytochrome C, placebo emulsion, and cytochrome C solution. The research was conducted in compliance with the ICH and FDA requirements and recommendations in relation to the development of HPLC methods of control of liposomal preparations.
 A method has been developed to enable the determination of encapsulation efficiency of cytochrome C in liposomal preparations and to allow for identifying the composition of liposomal nanoparticles of cytochrome C. This HPLC method has been validated in terms of specificity, limit of detection, and robustness in compliance with the recommended criteria. The technique may find its application in quality control of liposomal form of cytochrome C and in control points manufacturing process.

Co-delivery of pemetrexed and miR-21 antisense oligonucleotide by lipid-polymer hybrid nanoparticles and effects on glioblastoma cells

Combination therapy using anticancer drugs and nucleic acid is a more promising strategy to overcome multidrug resistance in cancer and to enhance apoptosis. In this study, lipid-polymer hybrid nanoparticles (LPNs), which contain both pemetrexed and miR-21 antisense oligonucleotide (anti-miR-21), have been developed for treatment of glioblastoma, the most aggressive type of brain tumor. Prepared LPNs have been well characterized by particle size distribution and zeta potential measurements, determination of encapsulation efficiency, and in vitro release experiments. Morphology of LPNs was determined by transmission electron microscopy. LPNs had a hydrodynamic size below 100 nm and exhibited sustained release of pemetrexed up to 10 h. Encapsulation of pemetrexed in LPNs increased cellular uptake from 6% to 78%. Results of confocal microscopy analysis have shown that co-delivery of anti-miR-21 significantly improved accumulation of LPNs in the nucleus of U87MG cells. Nevertheless, more effective cytotoxicity results could not be obtained due to low concentration of anti-miR-21, loaded in LPNs. We expect that the effective drug delivery systems can be obtained with higher concentration of anti-miR-21 for the treatment of glioblastoma.

Development and Characterization of a Gel Formulation Integrating Microencapsulated Nitrofurazone

Nitrofurazone (NTZ) is usually employed in the topical treatment of infected wounds and lesions of both skin and mucosa. Microencapsulation is a process utilized in the incorporation of active ingredients within polymers aiming at, among other objectives, the prolonged release of pharmaceutical compounds and protection from atmospheric agents (viz. moisture, light, heat and/or oxidation). With the goal of utilizing the microparticles containing encapsulated NTZ in pharmaceutical formulations, one prepared microparticles containing NTZ via ionotropic gelation of sodium alginate. The microparticles were characterized via scanning electron microscopy analyses, Fourier transform infrared spectroscopy (FTIR) analyses, via determination of encapsulation efficiency, and via thermal analyses (both TGA and DSC). The final gel formulation was also characterized rheologically. The extrusion/solidification technique employed to obtain the calcium alginate microparticles with encapsulated NTZ was found to be adequate, and produced an NTZ encapsulation efficiency of ca. 97.8% ± 1.1%. The calcium alginate microparticles thus obtained, with encapsulated NTZ, exhibited an oval shape and hydrodynamic diameters between 500 μm and 800 μm. From the thermal analyses performed, together with information from the infrared spectra, one may conclude that NTZ did not strongly bind to the polymer, which may be favorable for the release of the active ingredient. From the results obtained in the present research effort, one may conclude that the microparticles produced possess the potential to be utilized as carriers for NTZ in pharmaceutical formulations such as gels, ointments, and solutions.

Biological Activity of Liposomal Vanillin

This article presents a study of vanillin encapsulation inside multilamellar liposomes, with emphasis on the evaluation of antioxidant activity, the hemolytic effect, and the antisickling properties of these products. Egg phosphatidylcholine-cholesterol and egg phosphatidylcholine-cholesterol-1-O-decylglycerol liposomes were prepared by mechanical dispersion, all with vanillin included. Vesicles were characterized by determination of encapsulation efficiency and vanillin retention capacity. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. The hemolytic effect of liposomes was also evaluated by spectrophotometry, as well as the antisickling activity by the Huck test using optical microscopy. Results showed that the lipid composition of liposomes did not significantly affect the encapsulation efficiency. Stable vesicles were obtained with a high retention percentage of vanillin. Liposomes exhibited a high capture of the DPPH radical compared to free vanillin and 1-O-decylglycerol (C10) in solution. Vesicles caused no significant hemolisys in normal erythrocytes, nor in those coming from patients with sickle cell anemia. Vanillin encapsulated in liposomes retained its antisickling activity, with a greater effect for C10-containing vesicles. Our results show that vanillin encapsulation in liposomes is a way to enhance the pharmacologic properties of this molecule using a suitable vehicle.

Fish oil stabilisation by microencapsulation with modified cellulose

Fish oil is the richest dietary source of long-chain omega-3 polyunsaturated fatty acids (PUFA). Stabilisation of omega-3 PUFA against oxidation is an important task in food processing. The ability of modified celluloses to act as microencapsulating agents for fish oil was investigated. Fish oil microcapsules were produced by spray-drying of homogenised emulsions containing modified celluloses and maltodextrin as coating materials. The quality of microcapsules was evaluated by scanning electron microscopy, determination of encapsulation efficiency, peroxide value during storage and solubility in water. Methylocellulose (MC) and hydroxypropyl methylocellulose (HPMC) showed good emulsifying properties. Homogenisation of emulsions resulted in creation of high amount of stable foam. More damage occurred in the powders coated with HPMC. The oil retention level was very high, 98.5% (i.e. up to 400.0 g/kg ready powder). Samples with fish oil content of approximately 500.0 g/kg exhibited more structural damage impairing the stabilisation effect. This study indicates that the use of modified cellulose, especially MC, as a coating material for the preparation of spray-dried fish oil microcapsules improves the stability and the concentration of fish oil in the powder.

Entrapment of Peptidoglycans and Adamantyltripeptides into Liposomes: An HPLC Assay for Determination of Encapsulation Efficiency

The encapsulation of different immunomodulating peptides, the peptidoglycan monomer, its semisynthetic derivatives (Adamant-1-yl)-acetyl-peptidoglycan monomer and Boc-Tyr-peptidoglycan monomer, respectively, and of two diastereoisomers of adamantyltripeptides into the large negatively charged multilamellar liposomes was investigated. The reproducible quantitative method using HPLC was established for the determination of the entrapped compounds. It was shown that the tested compounds could be efficiently incorporated into liposomes using either the film or modified film method. The results confirmed that the peptidoglycans with lipophilic substituents and particularly the adamantyltripeptides were incorporated into liposomes with higher efficiency than the peptidoglycan monomer using either of the described methods. Liposome preparations were stable at 4°C up to seven days as shown by minimal leaking of the entrapped material.