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2022 ◽  
Vol 9 (1) ◽  
pp. 11
Author(s):  
Norhayati Mohamed Noor ◽  
Sana Umar ◽  
Azila Abdul-Aziz ◽  
Khalid Sheikh ◽  
Satyanarayana Somavarapu

Male pattern baldness (MPB) is a common condition that has a negative impact on the psycho-social health of many men. This study aims to engineer an alcohol-free formulation to cater for individuals who may have had allergic reactions to alcohol-based preparations. A lipid-based nanoparticle system composed of stearic and oleic acid (solid and liquid lipid) was used to deliver dutasteride (DST) for topical application. Two compositions, with oleic acid (Formulation A) and without (Formulation B), were compared to analyse the role of oleic acid as a potential active ingredient in addition to DST. DST-loaded LNP were prepared using the emulsification–ultrasonication method. All of the prepared formulations were spherical in shape in the nanometric size range (150–300 nm), with entrapment efficiencies of >75%. X-ray diffractograms revealed that DST exists in an amorphous form within the NLP matrices. The drug release behaviour from both LNP preparations displayed slow release of DST. Permeation studies through pig ear skin demonstrated that DST-LNP with oleic acid produced significantly lower permeation into the dermis compared to the formulation without oleic acid. These results suggest that the proposed formulation presents several characteristics which are novel, indicating its suitability for the dermal delivery of anti-androgenic molecules.


Author(s):  
Mahsa Yazdan-Bakhsh ◽  
Mojtaba Nasr-Esfahani ◽  
reza esmaeilzadeh kenari ◽  
Mohamad Fazel-Najafabadi

This study was carried out to optimize formulation for Heracleum Lasiopetalum (golpar) extract nanoencapsulation by response surface methodology (RSM). The primary emulsion was fabricated by (5-10 %) golpar extract (GE), (40-35 %) emulsifier span 80 (EM), and (50-60 %) sunflower oil (SO). The coating materials of nanoencapsulation were the composition of Lepidium sativum seed gum (LSG) and whey protein concentrate (WPC) at different ratios (1:0, 1:1, and 0:1). The yield of nanoencapsulation of golpar extract, particle size, and zeta potential was investigated as responses of RSM. The optimal formulation for nanoencapsulation of golpar extract were SO: 50.46%, GE 9.52%, and EM: 36.30% in LSG, SO: 57.07%, GE: 7.12%, and EM: 30.85% in LSG:WPC, and SO: 54.98%, GE: 9.05%, and EM: 39.87% in WPC coating. In conclusion, the nanoencapsulation of golpar extract prepared with the optimized formulation by RSM ensures the gradual release and sedimentation during storage with nanometric size and high yield of encapsulation. The nanocapsules of golpar extract can be used as a natural antioxidant in food systems.


2021 ◽  
Vol 8 ◽  
Author(s):  
Alexandra Cantarano ◽  
Denis Testemale ◽  
Estelle Homeyer ◽  
Hanako Okuno ◽  
Audrey Potdevin ◽  
...  

Y3Al5O12 (YAG) nanocrystals have been synthesized by a modified solvothermal method (300°C) allowing the incorporation of cerium ions in much larger proportion (up to 30 mol.% with respect to yttrium ions) than ever published. The reasons are the nanometric size of the produced nanocrystals, allowing to accommodate Ce3+ ions in the rigid YAG structure thanks to the presence of local distortions, and also the soft synthesis route, at low temperatures and far from the thermodynamic equilibrium, which favors the cerium insertion. As a consequence, Ce3+ photoluminescence spectrum can be tuned with the doping concentration, from 541 nm for low Ce3+ concentration to 580 nm for a cerium concentration of 30 mol.%. The internal quantum yield reaches 40 ± 5% before decreasing due to concentration quenching. The nanocrystal brightness, which combines the internal quantum yield and the cerium concentration, has been found optimal for a doping of 2 mol.% Ce3+.


2021 ◽  
Vol 5 (4) ◽  
pp. 50
Author(s):  
Laura Fernández-Peña ◽  
Boutaina Z. El Mojahid ◽  
Eduardo Guzmán ◽  
Francisco Ortega ◽  
Ramón G. Rubio

This work analyzes the dispersion of a highly hydrophobic molecule, (9Z)-N-(1,3-dihydroxyoctadecan-2-yl)octadec-9-enamide (ceramide-like molecule), with cosmetic and pharmaceutical interest, by exploiting oil-in-water microemulsions. Two different oils, oleic acid and soybean oil, were tested as an oil phase while mixtures of laureth-5-carboxylic acid (Akypo) and 2-propanol were used for the stabilization of the dispersions. This allowed us to obtain stable aqueous-based formulations with a relatively reduced content of oily phase (around 3% w/w), that may enhance the bioavailability of this molecule by its solubilization in nanometric oil droplets (with a size range of 30–80 nm), that allow the incorporation of a ceramide-like molecule of up to 3% w/w, to remain stable for more than a year. The nanometric size of the droplet containing the active ingredient and the stability of the formulations provide the basis for evaluating the efficiency of microemulsions in preparing formulations to enhance the distribution and availability of ceramide-like molecules, helping to reach targets in cosmetic and pharmaceutical formulations.


2021 ◽  
Vol 2015 (1) ◽  
pp. 012055
Author(s):  
Y Haddad ◽  
J Chrétien ◽  
S Margueron ◽  
J C Beugnot ◽  
G Fanjoux

Abstract We present in this work a non-destructive and non-invasive imaging spectroscopic technique with a high spatial and spectral resolution to characterize the light propagation behaviour along a centimetric length and nanometric size tapered optical fiber in operation.


Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1414
Author(s):  
Jesús Díaz ◽  
Jaime C. Gálvez ◽  
Marcos G. Alberti ◽  
Alejandro Enfedaque

This paper describes the packing models that are fundamental for the design of ultra-high-performance concrete (UHPC) and their evolution. They are divided into two large groups: continuous and discrete models. The latter are those that provide the best method for achieving an adequate simulation of the packing of the particles up to nanometric size. This includes the interaction among the particles by means of loosening and wall coefficients, allowing a simulation of the virtual and real compactness of such particles. In addition, a relationship between virtual and real compactness is obtained through the compaction index, which may simulate the energy of compaction so that the particles are placed in the mold. The use of last-generation additives allows such models to be implemented with water–cement (w/c) ratios close to 0.18. However, the premise of maximum packing as a basic pillar for the production of UHPC should not be the only one. The cement hydration process affected by nanoadditives and the ensuing effectiveness of the properties in both fresh and hardened states according to the respective percentages in the mixture should also be studied. The characterization tests of the aggregates and additions (dry and wet compactness, granulometry, density and absorption) have been carried out in order to implement them numerically in the polydisperse packing model to obtain the compactness of the mixture. Establishing fixed percentages of nanoadditives in the calculation of the mixture’s compactness. The adequate ratio and proportion of these additions can lead to better results even at lower levels of compactness. The compressive strength values obtained at seven days are directly proportional to the calculated compactness. However, at the age of 28 days, better results were obtained in mixes with lower cement contents, fewer additions and lower compactness. Thus, mixes with lower cement contents and additions (silica fume and limestone filler) with a compactness of φ = 0.775 reached 80.1 MPa of strength at 7 days, which is lower than mixes with higher cement contents and number of additions (SF, limestone filler and nanosilica), which achieved a compactness of φ = 0.789 and 93.7 MPa for compressive strength. However, at 28 days the result was reversed with compressive strengths of 124.6 and 121.7 MPa, respectively.


Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1162
Author(s):  
Marie Carrière ◽  
Paulo Henrique M. Buzzetti ◽  
Karine Gorgy ◽  
Muhammad Mumtaz ◽  
Christophe Travelet ◽  
...  

A series of new glyconanoparticles (GNPs) was obtained by self-assembly by direct nanoprecipitation of a mixture of two carbohydrate amphiphilic copolymers consisting of polystyrene-block-β-cyclodextrin and polystyrene-block-maltoheptaose with different mass ratios, respectively 0–100, 10–90, 50–50 and 0–100%. Characterizations for all these GNPs were achieved using dynamic light scattering, scanning and transmission electron microscopy techniques, highlighting their spherical morphology and their nanometric size (diameter range 20–40 nm). In addition, by using the inclusion properties of cyclodextrin, these glyconanoparticles were successfully post-functionalized using a water-soluble redox compound, such as anthraquinone sulfonate (AQS) and characterized by cyclic voltammetry. The resulting glyconanoparticles exhibit the classical electroactivity of free AQS in solution. The amount of AQS immobilized by host–guest interactions is proportional to the percentage of polystyrene-block-β-cyclodextrin entering into the composition of GNPs. The modulation of the surface density of the β-cyclodextrin at the shell of the GNPs may constitute an attractive way for the elaboration of different electroactive GNPs and even GNPs modified by biotinylated proteins.


Applied Nano ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 85-97
Author(s):  
Angelo Taglietti ◽  
Piersandro Pallavicini ◽  
Giacomo Dacarro

Prussian blue is an ancient artificial pigment. Its biocompatibility and the possibility of synthesizing it in nanometric size stimulated the interest of the scientific community. Many uses of Prussian blue nanoparticles have been reported in the field of nanomedicine. More recently, interest into the potential application of Prussian blue nanoparticles as antibacterial agents has spread. Literature regarding Prussian blue and its analogs as antibacterial materials is still limited, but the number of papers has grown quickly over the last 2–3 years.


NANO ◽  
2021 ◽  
pp. 2150049
Author(s):  
Ainun Nikmah ◽  
Ahmad Taufiq ◽  
Arif Hidayat ◽  
Sunaryono ◽  
Hendra Susanto

In this study, a new antimicrobial agent was developed through a synthesis of Fe3O4/SiO2/Ag double nanocomposites using the sol–gel method. The prepared samples were characterized using XRD, SEM, FTIR, UV-Vis, VSM, and antibacterial test. The data analysis results for the Fe3O4/SiO2/Ag composites showed that Fe3O4, SiO2, and Ag constructed respective spinel cubic, orthorhombic, and amorphous structures in nanometric size. The saturation magnetization of Fe3O4/SiO2/Ag nanocomposites decreased due to the increase in the Ag content. Interestingly, the Fe3O4/SiO2/Ag nanocomposites presented excellent microbial activity. Ag deposition on the Fe3O4/SiO2 surface enhanced the antimicrobial activity of nanocomposites because Ag oxidized to Ag[Formula: see text] ion to produce a toxic effect in the cells of microorganisms. Furthermore, the Ag[Formula: see text] ion created the –S–Ag bond chain and deactivated the microorganism cells. Furthermore, surface plasmon resonance of Ag had an impact on the formation of photo-induced electrons, which produced superoxide radical anions, [Formula: see text]O2− generating a collapsing force that causes the death of microorganisms.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Giada Cantono ◽  
Alexander Permogorov ◽  
Julien Ferri ◽  
Evgeniya Smetanina ◽  
Alexandre Dmitriev ◽  
...  

AbstractStructured solid targets are widely investigated to increase the energy absorption of high-power laser pulses so as to achieve efficient ion acceleration. Here we report the first experimental study of the maximum energy of proton beams accelerated from sub-micrometric foils perforated with holes of nanometric size. By showing the lack of energy enhancement in comparison to standard flat foils, our results suggest that the high contrast routinely achieved with a double plasma mirror does not prevent damaging of the nanostructures prior to the main interaction. Particle-in-cell simulations support that even a short scale length plasma, formed in the last hundreds of femtoseconds before the peak of an ultrashort laser pulse, fills the holes and hinders enhanced electron heating. Our findings reinforce the need for improved laser contrast, as well as for accurate control and diagnostics of on-target plasma formation.


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