Nanoemulsion as a topical delivery system of antipsoriatic drugs

Psoriasis is one of the most common skin diseases, affecting 2–5% of the world's population. It is a skin autoimmune disorder, resulting in an excessive growth and aberrant differentiation of keratinocytes. Psoriasis is an incurable lifetime disease which can only be controlled and relieved through medication. Various approaches have been explored to treat the disease. Treatment of psoriasis includes topical therapy, systemic therapy and phototherapy. Topical therapy is the first line treatment and it is the most practical medication method for psoriasis patients. However, the conventional topical treatments such as gel and cream have low efficiency, poor cosmetic and aesthetic appeal, leading to poor patient compliance or adherence, while systemic and photo therapy produce significant adverse side effects. Nanoemulsion is defined as an emulsion system consisting of oil, surfactant, and water with an isotropic, transparent (or translucent) appearance. The emulsion droplet size is defined to be less than 200 nm. Nonetheless, if the emulsion has low surfactant content and is kinetically stable, a size of less than 500 nm can be accepted as nanoemulsion. A small droplet size would enhance the delivery and penetration of a drug through the psoriasis skin layer. There has been a growing interest in using nanoemulsions in topical applications, due to their high stability and their optical transparency or translucency, which make them good and very dermatologically attractive. A good selection of oils and surfactants would enhance the transdermal treatment efficacy. This review highlights the potential of drug-loaded nanoemulsions for the treatment of psoriasis towards achieving better efficacy and eliminating side effects

Glycolipids from Natural Sources : Dry Liquid Crystal Properties, Hydrogen Bonding and Molecular Mobility of Palm Kernel Oil Mannosides

Acknowledgement This work was supported by the Ministry of Education of Malaysia [600-RMI/RAGS 5/3 (140/2014), 2014]; University Malaya [RP038B-17AFR, 2017]; Royal Academy of Engineering, U.K., and Academy of Science, Malaysia [NRCP1516/4/61, 2016] and the University of Aberdeen [SF10192, 2018]. AMF and TS would like to acknowledge the financial support provided by University Malaya for the Visiting Lecturer fellowshipPeer reviewedPostprin

Incommensurate Lamellar Phase from Long Chain Mannosides : Investigation by X-Ray Scattering and Replica Exchange Molecular Dynamics (REMD)

Acknowledgement This work was supported by the Ministry of Education of Malaysia [600-IRMI/FRGS 5/3 (357/2019)]. We are thankful for the computational facility provided by the National Center for High-Performance Computing of Taiwan used to perform calculations reported in this work. AMF would like to acknowledge the Scottish Government and the Royal Society of Edinburgh, for the award of one SAPHIRE project.Peer reviewedPostprin

Sucrose ester micellar-mediated synthesis of Ag nanoparticles and the antibacterial properties

Ag nanoparticles with diameter in the range of 10–25 nm had been synthesized using a simple sucrose ester micellar-mediated method. Ag nanoparticles were formed by adding AgNO3 solution into the sucrose ester micellar solution containing sodium hydroxide at atmospheric condition after 24 h of aging time. Trace amount of dimethyl formamide (DMF) in the sucrose ester solution served as a reducing agent while NaOH acted as a catalyst. The produced Ag nanoparticles were highly stable in the sucrose ester micellar system as there was no precipitation after 6 months of storage. The as-synthesized Ag nanoparticles were characterized using transmission electron microscope (TEM), X-ray diffractometer (XRD), dynamic light scattering (DLS) and UV–vis spectroscopy (UV–vis). Formation mechanism of Ag nanoparticles in the micellar-mediated synthesis is postulated. The antibacterial properties of the Ag nanoparticles were tested against Methicillin-resistant Staphylococcus aureus (MRSA) (Gram-positive) and Aeromonas hydrophila (Gram-negative) bacteria. This work provides a simple and “green” method for the synthesis of highly stable Ag nanoparticles in aqueous solution with promising antibacterial property

γ-ray assisted synthesis of silver nanoparticles in chitosan solution and the antibacterial properties

In the present study, chitosan had been utilized as a “green” stabilizing agent for the synthesis of spherical silver nanoparticles in the range of 5–30 nm depending on the percentage of chitosan used (0.1, 0.5, 1.0 and 2.0 wt%) under γ-irradiation. X-ray diffractometer identified the nanoparticles as pure silver having face-centered cubic phase. Ultraviolet–visible spectra exhibited the influence of γ-irradiation total absorbed dose and chitosan concentration on the yield of silver nanoparticles. The antibacterial properties of the silver nanoparticles were tested against Methicillin-resistant Staphylococcus aureus (MRSA) (gram-positive) and Aeromonas hydrophila (gram-negative) bacteria. This work provides a simple and “green” method for the synthesis of highly stable silver nanoparticles in aqueous solution with good antibacterial property

Sintesis dan pencirian kobalt sulfida menggunakan misel ester sukrosa dan kegunaan sebagai penjerap pewarna

Cobalt sulfide has been successfully formed using chemical precipitation method in the presence of 0.1% sucrose ester S1670s. X-ray diffraction (XRD) pattern of cobalt sulfide formed shows amorphous structure and EDX analysis shows atomic ratio for Co:S is 1:1.08 which is an evident of formation of CoS. Under the transmission electron microscope (TEM), CoS showed pores structure in the range of ∼ 10 nm and the result is in agreement with the BET results. The formation of pores structure in the CoS material is due to the structure of sucrose ester micelle which has diameter of ∼ 10 nm. Adsorption ability of CoS formed was tested using methylene blue as model dyes. The optimum absorption ability for CoS is 110mg/g while the most suitable pH for adsorption was greater than 6

Molecular dynamics simulations of the lyotropic reverse hexagonal (HII) of Guerbet branched-chain β-d-glucoside

Through atomistic molecular dynamic simulations using a GROMOS53a6 force field for the carbohydrate, we studied the lyotropic reverse hexagonal phase HII from a glycolipid, namely the Guerbet branched-chain β-d-glucoside, at 14% and 22% water concentrations. Our simulations showed that at low water concentration (14%) the sugar head group overlapped extensively and protruded into the water channel. In contrast, in the 22% concentration system a water column free from the sugar headgroup ('free' water) was formed as expected for the system close to the limit of maximum hydration. In both concentrations, we found anomalous water diffusion in the xy-plane, i.e. the two-dimensional space confined by the surface of the cylinder. On the other hand, along the z-axis, the water diffusion obeyed the Einstein relation for the 22% system, while for the 14% system it was slightly anomalous. For the 22% system, the diffusion along the z-axis of the 'free' water obeyed the Einstein relation, while that of the 'bound' water is slightly anomalous. The xy-plane displacement of the 'bound' water was higher than that for the 'free' water at times longer than 200 ps, as a consequence of the exchange of water molecules between the two regions. Based on our findings, we proposed an alternative explanation to the observed spatial heterogeneity in the HII phase from probe diffusion by Penaloza et al. (Phys. Chem. Chem. Phys., 2012, 14(15), 5247-5250). We found the extent of contact with water was different at different oxygen atoms within the sugar ring. Generally, a higher probability of hydrogen bonding but a shorter lifetime was found in 22% water compared to the case of 14% water. Finally, we examined the extension and compression of the alkyl chain of a columnar

Avalanche charge generation in anhydrous glucosides excited by an external electric field

Glycolipids are components of cellular membranes comprising a hydrophobic lipid tail and one or more hydrophilic sugar heads, and are widely associated with the fields of life science and biochemistry. Due to the hygroscopic nature of sugar, the dry thermotropic phases of glycolipids have fewer studies. We report on the electric charge generation in anhydrous glucosides excited by the external high electric field (∼2 MV/m). This causes a large current in the smectic A phase, but not in the isotropic phase. Its intensity is about 100 times larger than the steady state current. The generation of the current was found to be irreversible by the repetition of the field application. The large electric carrier generation is originated in the smectic A phase, possibly due to an electron avalanche breakdown mechanism caused by the collisions of electrons through the impact ionization. © 2019 Author(s)