Zeta Potential Determination Research Articles

Basic Concepts of Nanoemulsion and its Potential application in Pharmaceutical, Cosmeceutical and Nutraceutical fields

One of the widely efficient and noteworthy nanocarriers that could draw a great attention toward pharmaceutical fields is nanoemulsions (NEs). NEs are thermodynamically stable colloidal dispersions composed of two immiscible liquids, oil and water that mixed together using emulsifying agent (surfactant and co-surfactant). It regarded as pharmaceutical dosage form having droplet size within a nanometer range, hence it has extensively considered as carrier for delivering active agents. Such carrier is fabricated in order to overcome some obstacles associated with conventional drug delivery systems especially low bioavailability. The objective of this review is to present an overview about NE and its latest applications in diverse areas such as drug delivery, cosmeceutical and nutraceutical. Clarifications about different mechanisms of NEs development that are frequently used were provided. Correspondingly, popular characterization techniques for NEs such as determination of particle size, polydispersity index (PDI), zeta potential and viscosity were reviewed. Eventually, summary of physical and chemical instability in addition to the regulatory aspects of NE were provided.

The adsorption mechanism of synergic reagents and its effect on apatite flotation in oleamide-sodium dodecyl benzene sulfonate (SDBS) system

The usage of synergic reagents plays vital role in the effective flotation of phosphate ore. In this paper, the adsorption mechanism of synergic reagents and its effect on apatite flotation in oleamide-sodium dodecyl benzene sulfonate (SDBS) system were investigated via micro-flotation experiment, Zeta-potential determination, X-ray photo-electron spectroscopy (XPS), and Time-of-flight secondary ion mass spectrometry (ToF-SIMS). Experimental research represented that a highest recovery rate of 97.09% could be obtained when a mixed collector dosage of 4 × 10−4 mol/L was used with a molar ratio of oleamide to SDBS of 2:1 at pH = 9.0, and the recovery could be improved by ~4.87% comparing with the theoretical recovery rate of single collector. Results of Zeta potential and XPS indicated that the chemisorptions of C17H33CONH−, (C17H33CONH2)m and sulfonate species originated from the mixed collector onto apatite surfaces occurred. More importantly, the adsorption of amide could be reinforced in the presence of SDBS, and the N atomic concentration increased from 1.23% to 1.66%. The results of ToF-SIMS further confirmed that the normalized peak intensities of C4H5+ and C4H7+ for apatite-oleamide-SDBS sample showed a statistically increase comparing with corresponding results of apatite-oleamide sample, while the normalized peak intensities of C6H4+ presented an opposite trend comparing with that of apatite-SDBS sample. The whole thickness of the formed hydrophobic species on the apatite surfaces was approximately 40.29 nm. The synergistic effects of mixed collector were mainly attributed to the improvement of solubility and dispersion and the decrease in critical micelle concentration of oleamide in the presence of SDBS, which provided easy access to the interaction between C17H33CONH−, (C17H33CONH2)m and apatite surfaces. The results provided a new path for apatite flotation, and reinforced the theoretical basis for flotation technique of phosphate ore.

Formulation and Evaluation of Self Nano Emulsifying Drug Delivery System of Raloxifene Hydrochloride

Raloxifene hydrochloride (RLX) is a selective Estrogen-receptor modulator used to treat osteoporosis as well as breast and endometrial cancer prevention. The bioavailability of RLX is only 2% due to substantial pre-systemic clearance. The goal of this research was to customise and characterise RLX-loaded self-nanoemulsifying drug-delivery systems (SNEDDS) by using bioactive excipients that impact drug metabolism. The droplet size, zeta potential and drug content determination of optimized formulation (F-06) was found to be 147.5 nm, -28.8, 99.67% respectively. The drug release study from the nano formulation was studied in Phosphate buffer 6.8 for all the formulations F1,F2,F3,F4,F5,F6 and F7. The optimized formulation was found to be F6
 Keywords: Raloxifene hydrochloride, nanoemulsion, SNEDDS

Enhanced photocatalytic oxidation degradability for real cyanide wastewater by designing photocatalyst GO/TiO2/ZSM-5: Performance and mechanism research

Cyanide wastewater contains highly toxic contaminants such as free cyanide and metal-cyanide complex, it is necessary to find the appropriate degradation technologies. In this study, a simple and effective photocatalyst with enhanced adsorption and photocatalytic activity was developed. A new composite photocatalyst was successfully prepared by solid-state dispersion (SSD) method, which combined graphene oxide (GO), nano titanium dioxide (nano-TiO2) and silicon-based zeolite (ZSM-5). The techniques of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), N2 adsorption–desorption test, X-ray diffraction (XRD), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS) were used to characterize the samples. The experiments with different content of nano-TiO2, different wavelengths of light source, different catalyst dosage, control experiments of different materials, and the determination of pH value and zeta potential were also carried out. The results showed that the 3.0 g/L of GTZ-60 (GO/TiO2/ZSM-5 composite photocatalyst with a content of 60 wt% TiO2) has the highest photocatalytic degradation efficiency under ultraviolet wavelength which the degradation efficiency of total cyanide and copper could reach 98.73% and 98.96%, respectively. The degradation of total cyanide followed the pseudo-first-order kinetics. The photoelectric properties of GTZ-60 obviously improved the migration and separation of photogenerated electrons (e−) and holes (h+), so that high photocatalytic efficiency was obtained. XPS analysis showed that cyanide was finally degraded to carbon oxide and nitrogen oxide. Copper and zinc are removed in the form of copper (Ⅱ) and zinc (Ⅱ).

Negative Impact of Citral on Susceptibility of Pseudomonas aeruginosa to Antibiotics.

Essential oils (EOs) or their components are widely used by inhalation or nebulization to fight mild respiratory bacterial infections. However, their interaction with antibiotics is poorly known. In this study we evaluated the effects of citral, the main component of lemongrass oil, on in vitro susceptibility of Pseudomonas aeruginosa to antibiotics. Exposure of strain PA14 to subinhibitory concentrations of citral increased expression of operons encoding the multidrug efflux systems MexEF-OprN and MexXY/OprM, and bacterial resistance to anti-pseudomonal antibiotics including imipenem (twofold), gentamicin (eightfold), tobramycin (eightfold), ciprofloxacin (twofold), and colistin (≥128-fold). Use of pump deletion mutants showed that in addition to efflux other mechanisms were involved in this citral-induced phenotype. Determination of Zeta potential suggested that citral impairs the cell surface binding of aminoglycosides and colistin used at low concentrations (≤10 μg/mL). Moreover, experiments based on Raman spectroscopy and high-resolution mass spectrometry demonstrated formation of a Schiff base between the aldehyde group of citral and amino-groups of tobramycin and colistin. Chemical synthesis of tobracitryl, the imine compound resulting from condensation of citral and tobramycin, confirmed the loss of antibiotic activity due to adduct formation. Altogether these data point to the potential risk concern of self-medication with EOs containing citral in patients suffering from P. aeruginosa chronic lung infections and being treated with aerosols of aminoglycoside or colistin.

All-in-One Pediatric Parenteral Nutrition Admixtures with an Extended Shelf Life—Insight in Correlations between Composition and Physicochemical Parameters

The administration of three-in-one parenteral nutrition (PN) admixtures to pediatric patients requires special consideration, specifically concerning quality and physicochemical stability. The introduction of a new parenteral amino acid solution into the market prompted us to evaluate Aminoplasmal Paed-based PN admixtures’ stability. The study aimed to determine the physicochemical parameters of the chosen variations of PN admixtures and search for a correlation between its composition and those parameters. One hundred and sixty-eight variations of PN admixtures intended for patients weighing from 10 to 25 kg and aged from 1 to 12 years and differing in the quantitative composition of electrolytes were selected for the study. The samples were prepared using each of the four intravenous lipid emulsions dedicated to pediatric patients: Intralipid 20%, Clinoleic 20%, Lipidem 20%, and Smoflipid 20%. The stability of the PN admixtures was assessed by visual inspection and determination of pH, osmolality, zeta potential, and hydrodynamic mean droplet diameter (MDD) immediately upon preparation and after seven days of storage at the temperature of 5 ± 1 °C with light protection. Pearson’s correlation was used to quantify the relationships between selected ingredients of the PN admixtures and the physicochemical parameters. The PN admixtures were characterized by pH ranging from 5.91 to 7.04, osmolality ranging from 1238 to 1678 mOsm/kg, and zeta potential ranging from −41.3 to −2.16 mV. The changes in pH and osmolality after seven days of storage did not exceed 0.2 and 4.4%, respectively. The homogeneity of the PN admixtures was confirmed by determining the polydispersity index, which ranged from 0.06 to 0.2. The MDD of the studied formulas ranged from 235 to 395 nm and from 233 to 365 nm immediately upon preparation and after the storage period, respectively. Correlations between selected components of the PN admixtures and some physicochemical parameters were found. All Aminoplasmal Paed 10%-based PN admixtures were characterized by appropriate physicochemical quality to be administered via the central veins, both immediately upon preparation and after seven days of storage at the temperature of 5 ± 1 °C with light protection. The applied electrolyte concentrations ranges and types of lipid emulsions in the selected macronutrient quantitative compositions allowed the PN admixtures to remain stable for seven days within the specified limits.

Green-synthesis of Silver Nanoparticles by Hygrophila auriculata Extract: Innovative Technique and Comprehensive Evaluation

Abstract: Background: Metal nanoparticles are of great scientific interest as they bridge the gap between the bulk and atomic structures. A number of methods of synthesizing nanoparticles have been developed and can be grouped into top-down (physical), bottom-up (chemical) and biological methods. Physical methods are expensive due to continuous consumption of energy to maintain the high pressure and temperature employed in nanoparticle synthesis and requires highly sophisticated equipment. In the chemical synthesis of nanoparticles, generation of hazardous by-products as well as involvement of certain chemicals that are environmental contaminants is a major concern. As against this plant-mediated synthesis of nanoparticles employs green synthetic route, is clean, ecofriendly, cost effective, safe, convenient and beneficial technique for large-scale production of nanoparticles. Aim: The study focuses on green synthesis of silver nanoparticles using plant extract as reducing, capping and stabilizing agents. It has been reported that aqueous silver ions when exposed to plant leaf extract undergo reduction leading to formation of silver nanoparticles. Methods: In present study, silver nanoparticles were synthesized by using hydro alcoholic extract of Hygrophila auriculata whole plant as reducing agent. Results: Synthesis of silver nanoparticles was confirmed by UV spectroscopy, particle size analysis, zeta potential determination, Fourier Transform Infrared Resonance, X-Ray Diffraction, Scanning Electron Microscopy and Transmission Electron Microscopy. Conclusion: Plant mediated nanoparticle synthesis is a simple, reproducible and ecofriendly method for elucidation of silver nanoparticles. Data obtained reveals the role of hydro alcoholic extract of Hygrophila auriculata in silver nanoparticle synthesis. Key words: Green synthesis, Silver nanoparticles, Hygrophila auriculata, Characterization, Surface Plasmon resonance.

Formulation and in-vitro evaluation of niosomal gel of gatifloxacin

A novel drug delivery system provides the delivery of drugs at a required rate into the body during the period of treatment as directed by the body. Formulation and evaluation of Noisome containing gatifloxacin using different concentrations of the polymer for controlled release. Pre-formulation study confirms the purity of the drug and compatibility of the drug with excipients using FT-IR. Tween 80 was found significant with the experimental results. An extensive investigation is needed concerning the depth of penetration into the skin, determination of zeta potential, and confirmation of configuration of phospholipids in the lipid bilayer. A significant loss of entrapped drug was found at the end of three month period when liposomal dispersions were stored at high temperature i.e. 25±20C. All gels were found under pH range 7.0 to 7.4, Spreadability under the range 6.6 to 7.6 cm, % drug content 98 to 100%, the viscosity of gels 98 to 115cp, and % permeation found in rage 75 to 91%. Excellent % Permeation Gel formulation GF-4 was found 91%. The drug release at raised temperatures may be associated with the lipid degradation in the bilayers results in membrane packing defects them leaky.

Doping of graphitic carbon nitride with oxygen by means of cyanuric acid: Properties and photocatalytic applications

Bare and oxygen doped graphitic carbon nitride were synthetized by the thermal polymerization of melamine (CN-M) and the mechanical mixtures of melamine and cyanuric acid, respectively, at 550 °C for 4 h. The ratios of melamine and cyanuric acid were 1:0.5, 1:1 and 1:2 (CN-MCA1, CN-MCA2 and CN-MCA3). The content of oxygen increased from 1.88 wt% (CN-M) to 3.93 wt% (CN-MCA3) and the specific surface area increased from 14 to 41 m2 g−1. The prepared CN materials were characterized by the elemental analysis, UV-Vis diffuse reflectance, X-ray diffraction, Fourier transform infrared spectrometry, the physisorption of nitrogen, scanning electron and high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, the determination of zeta potentials, and the Mott-Schottky method.The addition of cyanuric acid led to partial changes in the CN morphology, as documented by occurrence of CN tubes, increase in the specific surface area and was a source of additional -O- and -OH moieties which modified the CN surface in addition to the spontaneous oxygenation observed in CN-M. The above effects positively influenced photocatalytic activity of the CN materials as demonstrated using Rhodamine B (RhB) and the Ofloxacin antibiotics. The photocatalytic decomposition of Ofloxacin was more efficient than that of RhB and differed in kinetics (first-order vs. zero-order reaction). The reusability and stability of the CN materials was verified by repeating batch photocatalytic decompositions of Ofloxacin experiments for five times.

Modification of malachite surfaces with lead ions and its contribution to the sulfidization flotation

Malachite is a common copper-oxide resource, and it is usually enriched by sulfidization flotation. Its floatability and recovery are greatly determined by the surface sulfidization results. In this paper, Pb(NO3)2 is used to pretreat malachite, and the sulfidization mechanism of malachite was studied through microflotation experiments, zeta-potential determination, adsorption tests, XPS and ToF-SIMS. The flotation and adsorption results show that the malachite floatability after pretreatment with Pb ions improved significantly. Compared with Na2S treatment, the maximum recovery increased by 42.6% after treatment with lead ions and Na2S. The zeta potential results showed that lead ions (such as Pb(OH)+) could adsorb on the malachite surface, and the surface active sites of malachite were increased. XPS results indicate that lead ions adsorbed onto the mineral surface through the interaction between Pb species, S species and O species. The formation for new species (such as Pb-S) enhanced the malachite sulfidization. ToF-SIMS was used to visualize the three-dimensional distribution of lead- and sulfur-species adsorbed on the malachite surface. It demonstrated that the sulfidization layer increased after pretreatment with Pb(NO3)2, facilitating the surface hydrophobicity and flotation recovery of malachite.

Antioxidant-Loaded Mucoadhesive Nanoparticles for Eye Drug Delivery: A New Strategy to Reduce Oxidative Stress

There are several approaches to treat ocular diseases, which can be invasive or non-invasive. Within the non-invasive, new pharmaceutical strategies based on nanotechnology and mucoadhesive polymers are emerging methodologies, which aim to reach an efficient treatment of eye diseases. The aim of this work was the development of novel chitosan/hyaluronic acid nanoparticle systems with mucoadhesive properties, intended to encapsulate antioxidant molecules (e.g., crocin) aiming to reduce eye oxidative stress and, consequently, ocular disease. An ultraviolet (UV) absorber molecule, actinoquinol, was also added to the nanoparticles, to further decrease oxidative stress. The developed nanoparticles were characterized and the results showed a mean particle size lower than 400 nm, polydispersity index of 0.220 ± 0.034, positive zeta potential, and high yield. The nanoparticles were also characterized in terms of pH, osmolality, and viscosity. Mucoadhesion studies involving the determination of zeta potential, viscosity, and tackiness, showed a strong interaction between the nanoparticles and mucin. In vitro release studies using synthetic membranes in Franz diffusion cells were conducted to unravel the drug release kinetic profile. Ex vitro studies using pig eye scleras in Franz diffusion cells were performed to evaluate the permeation of the nanoparticles. Furthermore, in vitro assays using the ARPE-19 (adult retinal pigment epithelium) cell line showed that the nanoparticles can efficiently decrease oxidative stress and showed low cytotoxicity. Thus, the developed chitosan/hyaluronic acid nanoparticles are a promising system for the delivery of antioxidants to the eye, by increasing their residence time and controlling their delivery.

Activation mechanism of lead ions in the flotation of sulfidized azurite with xanthate as collector

Metal ions are commonly used to activate oxide minerals and improve the collector adsorption on the mineral surface. In this work, lead ions were added after azurite was sulfidized with Na2S, and the effect of lead ions on the flotation of sulfidized azurite was investigated. Micro-flotation tests were performed to study the flotation behavior after sulfidized azurite was treated with lead ions, and the activation mechanism was revealed by zeta potential determination, X-ray photoelectron spectroscopy (XPS) analysis, time-of-flight secondary ion mass spectrometry (ToF-SIMS), Fourier-transform infrared (FT-IR) spectroscopy, and ultraviolet spectroscopy measurements. The flotation results showed that the azurite recovery increased when a low concentration of lead ions was poured into the pulp solution in the presence of Na2S. Zeta potential determination indicated that chemisorption occurred when the sulfidized azurite surface was modified with lead ions. The XPS results showed that Pb–S species formed on the sulfidized azurite surface treated with lead ions. ToF-SIMS analysis showed that S−, S2−, SO3−, and Pb2+ ions were present on the azurite surface and the thickness of the S species in the azurite–Na2S–Pb(II) system was larger than in the azurite–Na2S system. FT-IR showed that the interaction between the lead ions and sulfidized azurite surfaces improved the xanthate attachment to the mineral surface. These results illustrated that addition of lead ions after sulfidization of azurite with Na2S was beneficial to the flotation recovery of copper oxide ores containing azurite.

Encapsulation of Satureja khuzistanica jamzad essential oil in chitosan nanoparticles with enhanced antibacterial and anticancer activities

Satureja khuzistanica jamzad (SKJ), which is a member of Lamiaceae, has various proven effects such as antispasmodic and anti-inflammatory, anti-diabetic, antioxidant, and antifungal properties. However, the use of essential oil of plants is limited due to their inherent instability in the environment. Encapsulation with nanoparticles in the nanogel forms is one of their stabilization methods. The aim of this study was to synthesize nano-gel based on chitosan (CS) and extracts of SKJ essential oil, and to evaluate the antibacterial and anticancer activities. SKJ essential oil was extracted using water distillation method. Then, it was loaded on CS particles using two-step process as following: droplets formation and freezing. The Dynamic Light Scattering (DLS), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Zeta potential determination were used to evaluate the physical and chemical properties of CS-SKJ nanogel, which its result was acceptable. After confirmation of the loaded essential oil rate and releasing amount, the antibacterial effects were evaluated on five Gram-positive bacteria and five Gram-negative bacteria using microbroth dilution method. The encapsulation efficiency, size, polydispersity index, and zeta potential of nanoparticles were characterized were 30.74%, 571.00 nm, 0.451 and −67.2 mV, respectively. The results were significant not only on Gram-positive bacteria, but also on Gram-negative bacteria. The MIC range was between 7.8 and 500 µg/ml. The CS-SKJ nanogel has acceptable anticancer activities on KB and A549 tumor cell lines. the IC50 range was between 5.6 and 6.71 µg/ml. The results indicate that both CS particles and SKJ alone, and CS-SKJ nanogel could be considered as the outlook to produce new antimicrobial and anticancer drugs.

Adsorption characteristics of Pb(II) species on the sulfidized malachite surface and its response to flotation

Sulfidization flotation is the main method for recovering non-ferrous metals oxide minerals, and the sulfidization effect determines the flotation recovery of minerals. In this paper, the effect of Pb(II) on the flotation of malachite sulfidized with sodium sulfide was studied through microflotation experiments, zeta-potential determination, adsorption experiments, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The microflotation experiments revealed that the floatability of sulfidized malachite was increased after treatment with Pb(II), with the maximum flotation recovery reaching 89.8% under the experimental conditions. The zeta-potential measurements showed that Pb(II) species can adsorb on the sulfidized malachite surface, increased the active sites on the mineral surface, and promoted the adsorption of the collector. XPS analysis indicated that addition of Pb(II) changed the chemical environment of the sulfidized malachite surface, and the formation of Pb species (Pb–S) and S species (S2− and Sn2−) enhanced the sulfidization of malachite surfaces. ToF-SIMS surface and depth profile analysis were used to intuitively explore the adsorption of the reagents, and they confirmed the positive effect of Pb(II) on malachite sulfidization. These results illustrated that the adsorption of Pb(II) on the sulfidized malachite surface was conducive to its flotation recovery.

Green synthesis, characterization, enhanced functionality and biological evaluation of silver nanoparticles based on Coriander sativum.

The present study focused on the green synthesis of silver nanoparticles from Coriander sativum (CS) containing structural polymers, phenolic compounds and glycosidic bioactive macromolecules. Plant phenolic compounds can act as antioxidants, lignin, and attractants like flavonoids and carotenoids. Henceforth, silver nanoparticles (AgNPs) were prepared extracellularly by the combinatorial action of stabilizing and reduction of the CS leaf extract. The biologically synthesized CS-AgNPs were studied by UV-spectroscopy, zeta potential determination, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis to characterize and confirm the formation of crystalline nanoparticles. The synthesized nanoparticles demonstrated strong antimicrobial activity against all microbial strains examined with varying degrees. The scavenging action on free radicals by CS-AgNPs showed strong antioxidant efficiency with superoxide and hydroxyl radicals at different concentrations as compared with standard ascorbic acid. The presence of in vitro anticancer effect was confirmed at different concentrations on the MCF-7 cell line as revealed with decrease in cell viability which was proportionately related to the concentration of CS-AgNPs illustrating the toxigenic nature of synthesized nanoparticles on cancerous cells.

Development and Validation of Optical Methods for Zeta Potential Determination of Silica and Polystyrene Particles in Aqueous Suspensions.

Zeta potential is frequently used to examine the colloidal stability of particles and macromolecules in liquids. Recently, it has been suggested that zeta potential can also play an important role for grouping and read-across of nanoforms in a regulatory context. Although the measurement of zeta potential is well established, only little information is reported on key metrological principles such as validation and measurement uncertainties. This contribution presents the results of an in-house validation of the commonly used electrophoretic light scattering (ELS) and the relatively new particle tracking analysis (PTA) methods. The performance characteristics were assessed by analyzing silica and polystyrene reference materials. The ELS and PTA methods are robust and have particle mass working ranges of 0.003 mg/kg to 30 g/kg and 0.03 mg/kg to 1.5 mg/kg, respectively. Despite different measurement principles, both methods exhibit similar uncertainties for repeatability (2%), intermediate precision (3%) and trueness (4%). These results confirm that the developed methods can accurately measure the zeta potential of silica and polystyrene particles and can be transferred to other laboratories that analyze similar types of samples. If direct implementation is impossible, the elaborated methodologies may serve as a guide to help laboratories validating their own methods.

Porphyran-capped silver nanoparticles as a promising antibacterial agent and electrode modifier for 5-fluorouracil electroanalysis

In the present work, the green synthesis of silver nanoparticles (AgNPs) using the sulfated polysaccharide porphyran (PFR) as capping agent and d-glucose as reducing agent is described. PFR was extracted from red seaweed and characterized by employing 13C NMR and determination of total sugar, protein, and sulfate contents. The obtained AgNPs-PFR were characterized by using UV-VIS spectroscopy, zeta potential determination, FESEM, and TEM, which demonstrated that PFR was effective at capping the AgNPs, yielding stable suspensions. The AgNPs-PFR presented good antimicrobial properties against Gram-positive and Gram-negative bacterial strains (Staphylococcus aureus and Escherichia coli, respectively). The AgNPs-PFR were also employed as the modifier of carbon paste electrodes, which were efficiently applied as electrochemical sensors for the determination of 5-fluorouracil (5-FU), an important anticancer drug, through square wave voltammetry (SWV). The AgNPs-PFR improved the electrochemical properties of the electrodes, and enhanced their electroanalytical performance. The developed sensing device presented detection and quantification limits equal to 10.7 and 35.8 μmol L-1, respectively, towards 5-FU determination. The proposed electrochemical sensor successfully quantified 5-FU in a real pharmaceutical formulation, confirming its potential as a new promising analytical detection tool for 5-FU quality control purposes.

Self Nano-Emulsifying Drug Delivery System (SNEDDS) of Curcuma Mangga Val. Essential Oil and The Stability Study

Essential oil of Curcuma mangga Val. has been reported to have cytotoxic effect against cancer cell lines. But this oil is unstable in dispensing so that a self nano-emulsifying drug delivery system (SNEDDS) of the oil was conducted to solve the problem and improve its potency. In the study, optimization, verification, characterization, and stability test of the SNEDDS formula were carried out respectively by simplex lattice design (SLD) on Design Expert ver. 10 software, droplet size and Zeta potential determinations using particle size analyzer (PSA) instrument, as well as heating-cooling and freeze-thaw methods.
 The best SNEDDS formula resulted was Miglyol : Tween 80 : PEG 400 = 16.034% : 68.380% : 15.586%; with transmittance of 84.47 + 1.05%, droplet size of 15.75 nm, zeta potential of -8.54 mV, polydispersity index (PDI) of 0.188, emulsifying time of 49.67 + 1.7 seconds in distilled water, 24.33 + 4.19 seconds in artificial gastric fluid and 21.33 + 2.87 seconds in artificial intestine fluid. After a freeze-thaw test there was no change on the emulsion’s clarity, color, smell, as well as no separation, which means that the formula was stable thermodynamically.
 The optimum SNEDDS formula resulted has small particle size, better emulsifying time in artificial gastric and intestine fluids, as well as better thermodynamic stability, which in turn will improve the cytotoxic activity of the Curcuma mangga Val. rhizome oil toward cancer cells.

Nano-co-delivery of lipophosphoglycan with soluble and autoclaved leishmania antigens into PLGA nanoparticles: Evaluation of in vitro and in vivo immunostimulatory effects against visceral leishmaniasis

The aim of the present study was to encapsulate lipophosphoglycan molecule (LPG) which is one of the most immunogenic antigens of Leishmania parasites into PLGA nanoparticles with autoclaved or soluble leishmanial antigens, characterize synthetized nanoparticles with different methods and evaluate their in vitro/in vivo immunostimulatory activities to develop new vaccine candidates. PLGA nanoparticles including LPG and autoclaved leishmania antigen (ALA) or soluble leishmania antigen (ALA) were synthetized by double emulsion solvent evaporation method. The synthetized nanoparticles were characterized by SEM and Zeta-sizer instruments for determination of size, zeta potentials and polydispersity index (PDI) values. The antigen release profiles and encapsulation efficiencies were determined by UV–Vis spectroscopy. Griess reaction and ELISA tests were used for measurements of produced nitric oxide (NO) and cytokine levels of macrophages and splenocytes treated with nanoparticles. For determination of protective effects of nanoparticles, parasite reduction in livers and spleens of immunized mice were calculated by LDU values post-infection. According to results, (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs possessed the sizes of 253 and 307 nm respectively. Antigen-loaded nanoparticles elevated the released NO amounts from macrophages for 14 and 18-folds in contrast to control. Furthermore, synthetized nanoparticles significantly triggered macrophages to produce excessive levels of IFN-γ and IL-12 cytokines. Besides it was detected that vaccination of mice with (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs elicited approximately 80% protection from Visceral Leishmaniasis. Furthermore, (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs lead to 10 to 14-folds increase in secreted Th1 cytokine levels from splenocytes than control demonstrating abundantly stimulation of T cell response following to vaccination with nano-vaccine formulations. These results reveal that both (SLA-LPG) PLGA NPs and (ALA-LPG) PLGA NPs have excellent immunostimulatory activities and they are promising nanovaccine formulations for the prevention of leishmaniasis in near future.

Formulation and Evaluation of Polymeric Nanoparticle by Nano-Precipitation Method

Acyclovir is also known as Acyclovir, this drug is used for treatment of viral infection, particularly for treatment of herpes simplex viral infection. These are taken for month during treatment of herpes simplex viral infection. These are showing the action against all herps virus family. The acyclovir is poorly water-soluble drug. Due to that main aim is to increase the solubility of acyclovir in other solvent. The bioavailability of acyclovir is very less about (15-35%) because it has less oral route absorption. Due to that the acyclovir are given in intravenous route. When acyclovir is taken in oral route, the peak plasma concentration occurs after 1-2 h. The acyclovir having 9-33% of plasma protein binding. The BCS class of acyclovir are Class third (high solubility and Low permeability). Due to that acyclovir are formulate in the form of nanoparticle. Chitosan are the polymers which are used for the formulation of nanoparticle. The chitosan is found to be compatible with acyclovir. Formulation of acyclovir nanoparticle was done by Nano-precipitation method. Many evaluation tests performed during the formulation of Acyclovir nanoparticle mainly zeta sizer is use for the determination of particle size, zeta potential and PDI (poly disperse index) also performed evaluation of loading efficiency and % Drug entrapment.
 Keywords: Acyclovir, Chitosan, Zeta sizer and Nanoparticle.