Study of the stability of lipid nanoemulsions with oleic acid

This work presents the results of a study on the effect of ionic surfactant cetriltrimethylammonium chloride (CTAB) on the size and ζ-potential of lipid nanoemulsions composed of oleic acid, prepared by temperature phase inversion method and stabilized by nonionic surfactants — Tween 60, Span 60

Solid lipid nanoparticles with stearic acid stabilized with yttrium stearate

In this work, we studied the effect of yttrium stearate on the physicochemical properties of dispersions of solid lipid nanoparticles composed of stearic acid stabilized with nonionic surfactants (Tween 60, Span 60). The results showed that an increase in the concentration of yttrium stearate leads to increasing kinetic stability and decreasing the average size of the aggregates. Along with this, the average size of single particles remains practically unchanged and amounts to 35±5 nm.

A PRAGMATIC APPROACH TO TREAT LUNG CANCER THROUGH LOADING THEAFLAVIN -3,3’-DIGALLATE AND EPIGALLOCATECHIN GALLATE IN SPANLASTIC

Lung cancer has the highest mortality rate as compared to other cancers. The anti-proliferative and antioxidant potential of epigallocatechin gallate (EGCG) and Theaflavin -3,3’-digallate (TF3) can play a major role in treatment if delivered efficiently. To improve the chemical stability and medicinal potential of EGCG and TF3 in the respiratory tract, a spanlastic is developed which is composed of Tween-80, Span-60, and cholesterol which encapsulate EGCG and TF3 inside its vesicular structure and deliver it specifically to the target cancer cells. The cholesterol layer will produce efficient penetration while tween-80 and span-60 will help in easily deformability and lowers the interfacial tension hence, produces a small Z-average diameter which facilitates efficient penetration between layers of cells. The nano-vesicular structure ensures the APIs stability at alkaline pH (7.6) and also increases cellular antioxidant activity and Ferric reducing antioxidant powers values of APIs. Better encapsulation efficiency and safe consideration by MTT assay are major advantages of Spanlastic. The lung cancer cell loses the ability of apoptosis, which can revived with the help of a nano-vesicular system of EGCG and TF3 and in addition, there will be activation of several other properties such as cell arrest, activation of miR-210, suppression of cyclin D1, inhibition of MAPK, ERK, and JAK-STAT at their maximum potential. Furthermore, a special type of spacer and pMDI canister are developed in order to maximize the drug stability and efficiency of its delivery.

Streptomycin Sulfate–Loaded Niosomes Enables Increased Antimicrobial and Anti-Biofilm Activities

One of the antibiotics used to treat infections is streptomycin sulfate that inhibits both Gram-negative and -positive bacteria. Nanoparticles are suitable carriers for the direct delivery and release of drug agents to infected locations. Niosomes are one of the new drug delivery systems that have received much attention today due to their excellent biofilm penetration property and controlled release. In this study, niosomes containing streptomycin sulfate were prepared by using the thin layer hydration method and optimized based on the size, polydispersity index (PDI), and encapsulation efficiency (EE%) characteristics. It was found that the Span 60-to-Tween 60 ratio of 1.5 and the surfactant-to-cholesterol ratio of 1.02 led to an optimum formulation with a minimum of size, low PDI, and maximum of EE of 97.8 nm, 0.27, and 86.7%, respectively. The drug release investigation showed that 50.0 ± 1.2% of streptomycin sulfate was released from the niosome in 24 h and reached 66.4 ± 1.3% by the end of 72 h. Two-month stability studies at 25° and 4°C showed more acceptable stability of samples kept at 4°C. Consequently, antimicrobial and anti-biofilm activities of streptomycin sulfate–loaded niosomes against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were found significantly higher than those of free drug, and the minimum inhibitory concentration values decreased 4- to 8-fold. Furthermore, niosome-encapsulated streptomycin up to 1,500 μg/ml exhibited negligible cytotoxicity against the human foreskin fibroblasts cell line, whereas the free drug exhibited slight cytotoxicity at this concentration. Desired physical characteristics and low toxicity of niosomal nano-carriers containing streptomycin sulfate made them a demanded candidate for the treatment of current bacterial infections and biofilms.

Transferosomes a New Transformation in Research: A Review

The drugs mostly present are available with less bioavailability and the problem arises with less permeation or solubility so extensive work is done to enhance these mechanisms. Not only that drugs should pass hepatic metabolism, Inorder to improve its bioavailability they are formulated as transferosomes which can improve the patient compliance by delivering the drug through the transdermal-route. Soya lecithin is used as a phospholipid whereas Tween 60, Tween 80, Span 60 and Span 80 are used as edge activators. These formulations usually showed more entrapment efficiency. The reason behind this is due to the presence of more phospholipids and as the surfactant concentration increases drug release will be rapid. As our main aim is to enhance the bioavailability this can be achieved by optimizing the concentrations of phospholipid and surfactant one can attain a controlled release of drug through this drug delivery system.

Fabrication and Characterization of Azithromycin-Loaded Niosomes for Periodontitis Treatment

Azithromycin (AZM) is a potential drug for periodontitis treatment, but its poor water solubility could be problematic for local delivery to periodontal tissues. Entrapping AZM, which is a hydrophobic drug into niosomes, could effectively deliver drugs to the target site. This study aimed to design and fabricate azithromycin-loaded niosomes (NAZ) with desirable properties for intra-periodontal pocket administration. Span 60 and cholesterol were used to prepare niosomes with modified reverse phase evaporation method. NAZ were characterized and the effects of niosome composition were investigated. In vitro release and cell viability were evaluated. The results of this study indicated that with the specific ratio of Span 60 and cholesterol, the particle sizes of niosomes were in nano-sized (319 nm) with optimal zeta potential (-39.57 mV). Controlled release of AZM was achieved with release kinetic followed zero order model. NAZ exhibited low toxicity as cell viability was comparable to negative control.

Physical and chemical study of coated Candida cylindracea with sorbitan esters

A new effective biocatalyst was prepared by coating lipase from Candida cylindracea with sorbitan esters such as span 60 and 65. This biocatalyst was characterized by employing the Scanning Electron Microscopy, X-Ray diffraction patterns and a lipase assay. The type of surfactant used during the lipase modification process has shown significant effect in the lipase activity and the protein content of the modified lipase complex. It was found that catalytic behavior of modified lipase was greatly affected by the source of the used span. Span 65-coated Candida cylindracea lipase showed the highest conversion of 50% in enzymatic esterification of glucose and lauric acid.

Evaluation of sonication on stability-indicating properties of optimized pilocarpine hydrochloride-loaded niosomes in ocular drug delivery

Niosomes are increasingly explored for enhancing drug penetration and retention in ocular tissues for both posterior and anterior eye delivery. They have been employed in encapsulating both hydrophilic and hydrophobic drugs, but their use is still plagued with challenges of stability and poor entrapment efficiency particularly with hydrophilic drugs. As a result, focus is on understanding the parameters that affect their stability and their optimization for improved results. Pilocarpine hydrochloride (HCl), a hydrophilic drug is used in the management of intraocular pressure in glaucoma. We aimed at optimizing pilocarpine HCl niosomes and evaluating the effect of sonication on its stability-indicating properties such as particle size, polydispersity index (PDI), zeta potential and entrapment efficiency. Pilocarpine niosomes were prepared by ether injection method. Composition concentrations were varied and the effects of these variations on niosomal properties were evaluated. The effects of sonication on niosomes were determined by sonicating optimized drug-loaded formulations for 30 min and 60 min. Tween 60 was confirmed to be more suitable over Span 60 for encapsulating hydrophilic drugs, resulting in the highest entrapment efficiency (EE) and better polydispersity and particle size indices. Optimum sonication duration as a process variable was determined to be 30 min which increased EE from 24.5% to 42% and zeta potential from (−)14.39 ± 8.55 mV to (−)18.92 ± 7.53 mV. In addition to selecting the appropriate surfactants and varying product composition concentrations, optimizing sonication parameters can be used to fine-tune niosomal properties to those most desirable for extended eye retainment and maintenance of long term stability.

Simulation, In Vitro, and In Vivo Cytotoxicity Assessments of Methotrexate-loaded pH-Responsive Nanocarriers

In this study, pH-responsive niosomal methotrexate (MTX) modified with ergosterol was prepared for potential anticancer application. The prepared formulation had a size of 176.7 ± 3.4 nm, zeta potential of −31.5 ± 2.6 mV, EE% of 76.9 ± 2.5%, and a pH-responsive behavior in two different pHs (5.4 and 7.4). In-silico evaluations showed that MTX intended to make a strong hydrogen bond with Span 60 compartments involving N2 and O4 atoms in glutamic acid and N7 atom in pteridine ring moieties, respectively. The cytotoxic effects of free and pH-MTX/Nio were assessed against MCF7 and HUVECs. Compared with free MTX, we found significantly lower IC50s when MCF7 cells were treated with niosomal MTX (84.03 vs. 9.464 µg/mL after 48 h, respectively). Moreover, lower cell killing activity was observed for this formulation in normal cells. The pH-MTX/Nio exhibited a set of morphological changes in MCF7 cells observed during cell death. In-vivo results demonstrated that intraperitoneal administration of free MTX (2 mg/kg) after six weeks caused a significant increase in serum blood urea nitrogen (BUN), serum creatinine, and serum malondialdehyde (MDA) levels of rats compared to the normal control rats. Treatment with 2 and 4 mg/kg doses of pH-MTX/Nio significantly increased serum BUN, serum creatinine, and serum lipid peroxidation. Still, the safety profile of such formulations in healthy cells/tissues should be further investigated.