sorbitan-monooleate and sorbitan-monostearate

Surface functionalization enhances the properties and characteristics of polymeric nanocapsules (NCs) mainly due to the surface charge, surfactants, and polymer coating type. Curcumin (CUR) is a bioactive compound with several proven pharmacological properties and low bioavailability. This study aimed to develop anionic (poly-ɛ-caprolactone; PCL) and cationic (Eudragit. A two-level, three-factor design (polymer, Span type, and TPGS concentration) was used. The biological effects of CUR-loaded TPGS-coated cationic and anionic NCs were assessed in apomorphine-induced stereotyped behavior in rats.. The type of polymer (anionic or cationic) and Span. The CUR-loaded TPGS-coated NCs proved to be a promising brain delivery system.

Topics: Animals; Apomorphine; Behavior, Animal; Curcumin; Dopamine Agonists; Enzyme Inhibitors; Hexoses; Nanocapsules; Plants, Medicinal; Rats; Stereotyped Behavior; Treatment Outcome; Vitamin E

The present study was focused on investigating niosomal gels loaded with cholinergic drug; pilocarpine HCl, for prolonged precorneal residence time and improved bioavailability for glaucoma treatment. Pilocarpine HCl niosomes were prepared using various nonionic surfactants (span 20, span 60 and span 80), in the presence of cholesterol in different molar ratios by ether injection method. The selected formulations were incorporated into carbopol 934 and locust bean gum-based gels. TEM analysis confirmed that niosomes formed were spherical in shape and has a definite internal aqueous space with uniform particle size. Formulation F4 composed of span 60 and cholesterol (1:1) gave the highest entrapment (93.26 ± 1.75%) and slower release results after 8 hours (Q8h = 60.35 ± 1.87%) among other formulations. The

Topics: Administration, Ophthalmic; Animals; Chemistry, Pharmaceutical; Drug Delivery Systems; Drug Liberation; Drug Stability; Glaucoma; Hexoses; Intraocular Pressure; Liposomes; Particle Size; Pilocarpine; Rabbits

Niosomes are used in studies for drug delivery or gene transfer. However, their physical properties and features relative to liposomes are not well documented. To characterize and more rationally optimize niosome formulations, the properties of these vesicle systems are compared to those of liposomes composed of phosphatidylcholine and phosphatidylethanolamine lipids plus cholesterol. Niosomes are highly stable and only slightly more leaky than liposomes as assayed by calcein leakage; the permeability for ions (KCl) is higher than that of liposomes. Contrary to liposomes, the size of niosomes decreases substantially upon freezing in liquid nitrogen and subsequent thawing, as shown by cryo-EM and dynamic light scattering. The packing of niosomal membranes was determined by laurdan fluorescence and is slightly lower than that of liposomes. We did not succeed in the functional reconstitution of the L-arginine/L-ornithine antiporter ArcD2 in niosomes, which we attribute to the non-ionic nature of the surfactants. The antimicrobial peptides alamethicin and melittin act similarly on niosomes and liposomes composed of unsaturated components, whereas both niosomes and liposomes are unaffected when saturated amphiphiles are used. In conclusion, in terms of stability and permeability for drug-size molecules niosomes are comparable to liposomes and they may offer an excellent, inexpensive alternative for delivery purposes.

Topics: 1,2-Dipalmitoylphosphatidylcholine; Alamethicin; Antimicrobial Cationic Peptides; Arginine; Cholesterol; Cryoelectron Microscopy; Detergents; Drug Delivery Systems; Fluoresceins; Hexoses; Light; Lipids; Liposomes; Melitten; Nitrogen; Ornithine; Osmosis; Permeability; Phosphatidylethanolamines; Polysorbates; Scattering, Radiation; Surface-Active Agents

Cocoa butter crystallization in the presence of sorbitan mono- and triesters or canola oil was investigated. Solid-state surfactant esters accelerated early-stage cocoa butter solidification while suppressing later growth. Sorbitan tristearate showed the strongest effect, followed by sorbitan monostearate and sorbitan monopalmitate. Liquid-state surfactants suppressed cocoa butter crystallization at all time points, with sorbitan trioleate showing a stronger effect than sorbitan monooleate, which behaved in a similar fashion to canola oil. Via DSC, the palmitic and stearic-based surfactants only associated with cocoa butter's high-melting fraction, with the oleic acid-based surfactants and canola oil showing little influence. All sorbitan esters had little effect on polymorphism, whereas canola oil accelerated the form II-to-III-to-IV transition. The palmitic and stearic-based surfactants greatly reduced cocoa butter crystal size whereas the oleic acid-based surfactants and canola showed no notable effect. Overall, sorbitan esters impacted cocoa butter crystallization kinetics, though this depended on surfactant structure and concentration.

Topics: Crystallization; Dietary Fats; Esters; Hexoses; Kinetics; Stearates; Surface-Active Agents

In this work, positively charged nanocapsules have been developed for potential ocular delivery exploiting the deposition of PLA onto the droplet surface of a W/O nanoemulsion prepared by the reversed procedure of the PIT method. PLA in combination with different amounts of various oils and surfactants have been studied in order to select the best formulation for polymeric nanocapsule preparation. The traditional visual observation together with the Turbiscan(®) technology were exploited in order to identify the best combination of polymer/oil for nanocapsule preparation. Two different primary surfactants (Span(®) 60 and Span(®) 80) have been tested to select their influence on the field of existence of the nanoemulsion by the construction of the pseudoternary phase diagrams. Cationic hybrid NC have been prepared by the addition of a coating layer of DDAB. The physico-chemical and morphological properties of all the prepared nanocapsules have been evaluated and compared by PCS, DSC and AFM. Therefore, positively charged nanocapsules can be easily prepared by a simple eco-friendly technique that exploits biocompatible materials avoiding a large input of mechanical energy as a potential ocular delivery systems for hydrophilic compounds or gene materials.

Topics: Drug Carriers; Emulsions; Green Chemistry Technology; Hexoses; Lactic Acid; Microscopy, Atomic Force; Nanocapsules; Oils, Volatile; Phase Transition; Polyesters; Polymers; Quaternary Ammonium Compounds; Static Electricity; Surface Properties; Surface-Active Agents

A novel method for the manufacture of protein/peptide-containing submicron particles was developed in an attempt to provide particles with increased activity while using high energy input technologies. The method consists of antisolvent co-precipitation from an aqueous solution containing both an amino acid core material (e.g. D,L-valine), and either bovine serum albumin (BSA) or lysozyme (Lys) as model proteins. The aqueous solution was added to the organic phase by means of a nebulizer to increase the total surface area of interaction for the precipitation process. Sonication proved to be an effective method to produce small particle sizes while maintaining high activity of Lys. The use of a polysorbate or sorbitan ester derivatives as stabilizers proved to be necessary to yield submicron particles. Particles with very high yields (approximately 100%) and very high activity after manufacture (approximately 100%) could be obtained. A particle size of 439.0 nm, with a yield of 48.8% and with final remaining activity of 98.7% was obtained. By studying various factors using a design of experiments strategy (DoE) we were able to establish the critical controlling factors for this new method of manufacture.

Topics: Animals; Cattle; Chemical Precipitation; Drug Carriers; Drug Compounding; Drug Stability; Excipients; Hexoses; Microscopy, Electron, Scanning; Models, Molecular; Muramidase; Particle Size; Polysorbates; Protein Stability; Quality Control; Serum Albumin, Bovine; Solubility; Sonication; Surface Properties; Surface-Active Agents; Valine

Curcuminoids (curcumin, desmethoxycurcumin, and bisdesmethoxycurcumin) are major bioactive substances found in turmeric (Curcuma longa L.) extracts and possess antioxidant, anti-inflammatory, antimicrobial and anticancer properties. In this study, curcuminoid niosomes prepared with a series of Span non-ionic surfactants were developed to enhance the skin permeation of curcuminoids. Formulations were evaluated based on aggregation of niosomes, curcuminoid loading, % entrapment efficiency and in vitro permeation of curcuminoids through shed snake skin. Optimal formulations of curcuminoid niosomes including sorbitan monooleate, cholesterol, and Solulan C-24 at a mole ratio of 47.5:47.5:5 were obtained. Up to 11 micromoles of curcuminoids could be loaded in the niosome with a % entrapment efficiency of 83%. About 90% of the niosomes had a diameter of 12.25 +/- 5.00 microm. The niosomes significantly enhanced permeation of curcuminoids compared with a methanolic solution of curcuminoids: 4% of entrapped curcuminoids traversed the shed snake skin, whereas permeation from the methanolic solution was undetectable. The fluxes of curcumin, desmethoxycurcumin, and bisdesmethoxycurcumin were 1.117, 0.263, and 0.057 microg/(cm2h), respectively, consistent with the relative hydrophobicity of curcumin > desmethoxycurcumin > bisdesmethoxycurcumin. In conclusion, our data show that curcuminoids can be successfully formulated as niosomes and that such formulations have improved properties for transdermal delivery.

Topics: Animals; Chemistry, Pharmaceutical; Cholesterol; Chromatography, High Pressure Liquid; Curcumin; Hexoses; In Vitro Techniques; Indicators and Reagents; Liposomes; Microscopy, Electron, Scanning; Particle Size; Permeability; Reproducibility of Results; Skin Absorption; Snakes; Surface-Active Agents

The aim of the study was to investigate the possibility of incorporating non-ionic surfactants into pellets produced from microcrystalline cellulose by the process of extrusion/spheronization and the properties of the pellets. A hydrophilic surfactant, polysorbate 60 (PS 60), and two hydrophobic surfactants, sorbitan monostearate (S 60) and sorbitan monooleate (S 80), were included in the water used to form the pellets in concentrations ranging from 5 to 95%. The presence of the surfactants influenced the type of the extrusion profile and improved the ability to provide round pellets, and the addition of the surfactants changed the range of liquid levels required to prepare the pellets. At a low level, i.e., 5%, all the surfactants increased the range of water contents possible, compared to the use of water alone. At high surfactant levels, the level of liquid, which could be used, became restricted. The median size of the pellets was dependent on the type of surfactant and the concentration included in the formulation. The range of sizes produced was generally quite narrow and there were many systems with more than 90% of the pellets in the modal fraction. The highest concentration of the surfactant in water that can be used to form pellets ranged from 50% for S 60, to 80% for S 80 and 95% for PS 60. The maximum amount of the surfactant, which could be incorporated into the final pellet, however, was found to be approximately 22.5% for both the hydrophobic surfactants and 32.5% for the hydrophilic surfactant.

Topics: Cellulose; Chemistry, Pharmaceutical; Dosage Forms; Excipients; Hexoses; Hydrophobic and Hydrophilic Interactions; Particle Size; Polysorbates; Surface-Active Agents; Water

Creams from three components, surfactant, purified water and oil, were prepared. Comparable molar fractions of components were used in order to better understand the structural properties of the components used. The surfactants were sorbitan monoesters, sorbitan monolaurate, monopalmitate, monostearate and monooleate, which differed from each other in the length or structure of the hydrocarbon chain. The oils used were isopropylpalmitate and myristate, and they differed from each other in the length of the fatty acid chain. Rheological properties, droplet size distributions and types (either o/w or w/o) of the creams were studied. The rheological tests used were oscillation stress sweep test, creep recovery test and viscosity test. The modelling of the creep phase was based on the creep recovery test. Sorbitan monolaurate and monostearate formed w/o creams, sorbitan monopalmitate and monooleate o/w creams. It appeared that the double-bonded structure of the surfactant made the cream less elastic. Elasticity was increased due to lengthening of the alkyl chain of the surfactant and increased amount of surfactant. Also the lengthening of the fatty acid chain of the oil made the creams more elastic. The results of the rheological tests and droplet size distributions correlated well each other. According to the modelling of the creep phase, creams could be represented either with the Burger model or with the Maxwell model.

Topics: Elasticity; Hexoses; Ointments; Rheology; Surface-Active Agents

Using the analytical constants for sorbitan monolaurate, monopalmitate, monostearate, and monooleate given in the National Formulary (NF), calculations were carried out that indicated that these emulsifiers are esters of sorbitol mono- and dianhydrides. Contrary to the NF description, no significant amount of sorbitol ester was calculated to be present, in agreement with recent experimental findings. Further calculations were made using the NF-defined analytical constants of polysorbate 20, polysorbate 40, polysorbate 60, and polysorbate 80, which indicate that these emulsifiers are esters primarily of polyoxyethylated sorbitol monoanhydride (i.e., sorbitan), with lesser quantities of polyoxyethylated esters of sorbitol dianhydride. Since all hydroxyl groups of the polysorbates are primary, random distribution of acyl groups on the available hydroxyls can be assumed, and the likely composition of these emulsifiers can be calculated. The most abundant compounds appear to be polyoxyethylated sorbitan mono-, di-, and triesters. Although the polysorbates are stated to contain 20 moles of ethylene oxide per mole of ester, the oxyethylene contents stated in the Food Chemicals Codex reveal that somewhat more than 20 moles of ethylene oxide are combined.

Topics: Chemistry, Pharmaceutical; Excipients; Hexoses; Pharmacopoeias as Topic; Polysorbates; United States

A rapid and sensitive spectrophotometric method has been developed to quantitate the peroxides present in sorbitan monooleate and monostearate. The method relies on the peroxide conversion of iodide to iodine. The method has also been found to work for polysorbate 60.

Topics: Hexoses; Peroxides; Spectrophotometry