Properties Of Different Formulations Research Articles

Novel adhesive based on black soldier fly larvae flour for particleboard production

Protein-based adhesives are receiving considerable attention due to their potential to contribute to the development of environmentally friendly materials. Black soldier fly larvae (BSFL) can convert organic waste into high value-added products, such as proteins and fatty acids. The objective of this study is to formulate adhesives from BSFL flour and evaluate their suitability in the production of particleboards. To expose the functional groups of the proteins for reaction with the wood, denaturation strategies involving alkaline treatments were assessed. The effectiveness of these treatments was evaluated through Bradford solubility, SDS-PAGE, and FTIR analysis. Bradford analysis confirmed that the alkali treatment increased the protein solubility from 10.1 g/l for 0 M to 89.1 g/l for 1 M. FTIR analysis revealed changes in the relative intensity of bands attributable to the Amide I, II, and III regions, which are associated with the α-helix and β-sheet structures. The adhesive was applied in the manufacturing process via spraying, requiring an evaluation of the rheological properties of different formulations. Based on the rheological properties, the viscosities of 0.25 M and 1 M were measured at 0.082 Pa·s and 0.113 Pa·s, respectively, falling within the suggested range for particleboard manufacture. Subsequently, eucalyptus wood panels were manufactured using the BSFL-based adhesives, and their mechanical properties as well as water resistance were evaluated. Static bending and tensile strength perpendicular to the surface testing revealed that boards produced with BSFL adhesive exhibited mechanical values comparable to those of commercial resins. The performance of the manufactured materials was compared with the minimum standards outlined in international regulations.

Toxicity and anti-diabetic effectiveness of polymeric nanoparticles containing natural compounds

Objective: To develop the nanoparticle formulations, characterization and evaluation of safety and in vivo anti diabetic potential by using experimental animal model.
 Methods: Different nano formulations such as Cur-nanoparticles, Pip-nanoparticles as well as Cur-Pip dual drug loaded nanoparticles were developed by nano co-precipitation method. The developed formulations were subjected for FT-IR analysis to determine the drug-drug and drug-polymer interaction. The Differential Scanning Colorimetric (DSC) study was carried out to observe the glass transition. Surface topography of nano formulations were carried out by Scanning Electron Microscopy (SEM). X-ray diffraction study was carried out to determine the crystalline properties of different formulations. Particle size of the polymeric nanoparticles was evaluated by Zeta sizer of nanoseries. Toxicity of nanoformulation was evaluated as per OECD guideline-407. For evaluation of therapeutic effectiveness, in-vivo anti-diabetic potential of nano formulations, the Streptozotocin (STZ) induced diabetes model was considered.
 Results: The developed formulations were spherical in shape and smooth surfaced. There were no interaction between the drugs and polymers. The result of toxicity study revealed that, there were no changes in behavior, food intake; hematology as well as biochemical parameters were observed that indicates the developed formulation is completely safe. The anti-diabetic effect of different formulations was screened against Streptozotocin induced diabetes in experimental animals. All the formulations were proved as effective in restoring blood glucose level however, Cu+Pi NP (184.15) group showed highest anti diabetic activity in comparison to control group (207.93)
 Conclusions: From this study, it was observed that, Curcumin-Piperine dual drug loaded nanoparticles exhibit better anti diabetic potential in comparison to control and Curcumin-NP treated group.
 Keywords: Nanoparticles, Streptozotocin, anti-diabetes, toxicity, hematology, biochemical

Formulation and Evaluation of Nutritional Properties and Shelf Life of Buckwheat Incorporated Nutri Ball

Objectives: To formulate and evaluate the nutritional composition and shelf life of buckwheat incorporated nutri ball. Methods: The moisture, fat, total ash in the control and various percentage of buckwheat incorporated nutri balls were analysed by using American Association of Cereal Chemists (AACC, 2000). The quantity of protein was estimated using the micro Kjeldahl method supported by AOAC. AOAC (1999) method was employed to quantify dietary fibre. Total phenolics, flavonoids and antioxidants analysis were done in methanolic extract of the various formulations of buckwheat nutri ball. Findings Nutritional analyses indicated that higher levels of protein (13.560.16), fiber (6.070.13), total phenolic content (5.970.11), total antioxidant capacity (34.210.17) and total flavonoids (2.960.03) were observed in 30% of buckwheat flour incorporated nutri balls. The total phenolics, flavonoids and antioxidant capacity was notably improved on the addition of buckwheat flour. Color properties of different formulations of buckwheat nutri balls showed decrease in l*, a* and b* values. The storage results indicated that the developed Nutri balls were sensorily satisfactory for up to two months when it is stored at room temperature. Moreover, raise in buckwheat flour content from 0 to 30% resulted in an insignificant difference from sensory scores of control. Hence, it is concluded that 30% buckwheat incorporated nutri balls are more acceptable. Novelty: This study proves that the novel gluten free nutri balls has plenty of bio active compounds. Keywords: Buckwheat; nutri balls; proximate analysis; sensory attributes; shelflife

Preparing a Personalized Meal by Using Soy, Cricket, and Egg Albumin Protein Based on 3D Printing.

Recently, personalized meals and customized food design by means of 3D printing technology have been considered over traditional food manufacturing methods. This study examined the effects of different proteins (soy, cricket, and egg albumin protein) in two concentrations (3% and 5%) on rheological, textural, and 3D printing characteristics. The textural and microstructural properties of different formulations were evaluated and compared. The addition of soy and cricket protein induced an increase in yield stress (τ₀), storage modulus (G′), and loss modulus (G″) while egg albumin protein decreased these parameters. The textural analysis (back extrusion and force of extrusion) demonstrated the relationship between increasing the amount of protein in the formula with an improvement in consistency and index of viscosity. These values showed a straight correlation with the printability of fortified formulas. 3D printing of the different formulas revealed that soy and cricket proteins allow the targeting of complex geometry with multilayers.

Preparation and Characterization of α-Tocopherol-Loaded Nano-Lipid Carriers: Effect of Lipid Type and Carrier Oil Content

Nano lipid carriers for encapsulating α-tocopherol (α-TC) were successfully fabricated using hot homogenization method. The effect of oil content and type of lipid on the physicochemical properties of different formulations was investigated. The results showed that α-TC nanocarriers exhibited a small particle size (259.2-379 nm), narrow polydispersity index (PDI) (0.178-0.432) and high entrapment efficiency (EE) (95.73-99.22%). Nanostructured lipid carrier (NLC) of Compritol containing 45% corn oil (α-TC-NC45) was selected as the optimum formulation due to its smaller particle size and PDI and higher EE. The differential scanning calorimetry (DSC) and X-ray diffractometry (XRD) data revealed a low degree of crystalinity for α-TC-NC45 with two crystal forms of α and s´. Transmission electron microscopy (TEM) images also exhibited an almost spherical morphology for the particles. The α-TC-NC45 was found to be stable with respect to particle size, PDI and EE during a 3-month storage at both 4 and 25 °C. The results concluded that Nanostructured lipid carrier of Compritol containing 45% corn oil may be announced as an appropriate delivery system for food and beverages fortification with α-tocopherol

Formation and characterization of core-shell CL-20/TNT composite prepared by spray-drying technique

The core-shell 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane/2,4,6-Trinitrotoluene (CL-20/TNT) composite was prepared by spray-drying method in which sensitive high energy explosive (CL-20) was coated with insensitive explosive (TNT). The structure and properties of different formulations of CL-20/TNT composite and CL-20/TNT mixture were characterized by scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Laser particle size analyzer, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), differential scanning calorimetry (DSC), impact sensitivity test and detonation performance. The results of SEM, TEM, XPS and XRD show that ϵ-CL-20 particles are coated by TNT. When the ratio of CL-20/TNT is 75/25, core-shell structure is well formed, and thickness of the shell is about 20–30 nm. And the analysis of heat and impact show that with the increase of TNT content, the TNT coating on the core-shell composite material can not only catalyze the thermal decomposition of core material (CL-20), but also greatly reduce the impact sensitivity. Compared with the CL-20/TNT mixture (75/25) at the same ratio, the characteristic drop height of core-shell CL-20/TNT composite (75/25) increased by 47.6% and the TNT coating can accelerate the nuclear decomposition in the CL-20/TNT composites. Therefore, the preparation of the core-shell composites can be regarded as a unique means, by which the composites are characterized by controllable decomposition rate, high energy and excellent mechanical sensitivity and could be applied to propellants and other fields.

Inhalable Nanoparticles/Microparticles of an AMPK and Nrf2 Activator for Targeted Pulmonary Drug Delivery as Dry Powder Inhalers

Metformin is an activator of the AMPK and Nrf2 pathways which are important in the pathology of several complex pulmonary diseases with unmet medical needs. Organic solution advanced spray drying in the absence of water in closed-mode was used to design and develop respirable dry powders. Following comprehensive characterization, the influence of physicochemical properties was correlated with performance as aerosols using inertial impaction and three different human dry powder inhaler (DPI) devices varying in device properties. In vitro cell assays were conducted to test safety in 2D human pulmonary cell lines and in 3D small airway epithelia comprising primary cells at the air-liquid interface (ALI). In addition, in vitro transepithelial electrical resistance (TEER) was carried out. Metformin remained crystalline following advanced spray drying under these conditions. All SD powders consisted of nanoparticles/microparticles in the solid state. In vitro aerosol dispersion performance showed high aerosolization for all SD metformin powders with all DPI devices tested. High emitted dose for all powders with all three DPI devices was measured. Differences in other aerosol performance parameters and the interplay between the properties of different formulations produced at specific pump rates and the three different DPI devices were correlated with spray drying pump rate and device properties. Safety over a wide metformin dose range was also demonstrated in vitro. Aerosol delivery of metformin nanoparticles/microparticles has the potential to be a new “first-in-class” therapeutic for the treatment of a number of pulmonary diseases including pulmonary vascular diseases such as pulmonary hypertension.

Factors affecting performance and manufacturability of naproxen Liqui-Pellet

AimLiqui-Pellet is potentially an emerging next-generation oral pill, which has shown promising results with unique advantages as well as displaying potential for commercial feasibility. Since Liqui-Pellet technology is still in its infancy, it is important to explore the parameters that can affect its performance, particularly the drug release rate. Therefore, the aim of this study is to investigate thoroughly the effect of Avicel PH101 (carrier) and Aerosil 300 (coating material) ratio (R-value) in Liqui-Pellet.MethodsKey parameter for Liqui-Pellet formulation in this study was the ratio of carrier and coating material. Tests were carried out to assess the physicochemical properties of different formulations. This involved looking into particle size, robustness, flowability, solid-state and drug release profile. The morphology of Liqui-Pellet was investigated by SEM.ResultsIt is found that R-value does not have a major effect on the success of Liqui-Pellet production. However, R-value does seem to have an effect on Liqui-Pellet size at a certain water content level and a slight effect on the drug release rate. A decrease in Avicel PH101 concentration and an increase in Aerosil 300 concentration in Liqui-Pellet formulations can reduce Liqui-Pellet size and slightly increase drug release rate by 9% after 2 h. The data shows Liqui-Pellet is resistant to friability, able to achieve exceptional flow property and have smooth surfaces, which is critical for applying coatings technology. Such properties are ideal in terms of commercial manufacturing. The XRPD and DSC both show the reduction in formulation crystallinity, which is expected in Liqui-Pellet formulation as a result of solubility of the drug in the co-solvent used in the preparation of Liqui-Pellets.ConclusionOverall it seems that R-value can affect Liqui-Pellet drug release rate and size but not on the production success rate.Graphical abstract

Physico-chemical properties of different formulations of pequi pulp with milk

The objective of this work was to perform the physical-chemical characterization of different formulations of the pequi pulp with the addition of different concentrations of whole milk, in order to identify promising products for commercial use. Three formulations of pequi pulp with whole milk were prepared: PL1- 90% pequi pulp and 10% milk, PL2 - 70% pequi pulp and 30% milk, PL3 - 50% pequi pulp and 50% milk. The formulations were evaluated for physical and physical-chemical parameters of color, water activity, water content, ash, total soluble solids (SST), pH, total titratable acidity (ATT), SST/ATT ratio, ascorbic acid, proteins, lipids, total, reducing and non-reducing sugars. The data obtained were subjected to analysis of variance (ANOVA) and comparison between means by the Tukey test at 5% probability. Among the three tested formulations, the best results were obtained for PL3, where it presented lower total titratable acidity, water activity, red intensity, yellow intensity and chromaticity, however, higher content of total soluble solids, ratio SST/ATT, ash, lipids, sugars (total, dimmer and non-dimmer), luminosity and tint angle. The inclusion of milk in the pequi pulp changed the physical and physical-chemical characteristics of the pulp, and it can be an alternative to add nutritional value to the fruit and consequently a promising product for the market.

Tailoring Gellan Gum Spongy-Like Hydrogels' Microstructure by Controlling Freezing Parameters.

Gellan gum (GG) spongy-like hydrogels have been explored for different tissue engineering (TE) applications owing to their highly attractive hydrogel-like features, and improved mechanical resilience and cell performance. Although the whole process for the preparation of these materials is well-defined, we hypothesized that variations occurring during the freezing step lead to batch-to-batch discrepancies. Aiming to address this issue, two freezing devices were tested, to prepare GG spongy-like hydrogels in a more reproducible way. The cooling and freezing rates, the nucleation time and temperature, and the end freezing time were determined at different freezing temperatures (−20, −80, and −210 °C). The efficacy of the devices was assessed by analyzing the physicochemical, mechanical, and biological properties of different formulations. The cooling rate and freezing rate varied between 0.1 and 128 °C/min, depending on the temperature used and the device. The properties of spongy-like hydrogels prepared with the tested devices showed lower standard deviation in comparison to those prepared with the standard process, due to the slower freezing rate of the hydrogels. However, with this method, mean pore size was significantly lower than that with the standard method. Cell entrapment, adhesion, and viability were not affected as demonstrated with human dermal fibroblasts. This work confirmed that batch-to-batch variations are mostly due to the freezing step and that the tested devices allow fine tuning of the scaffolds’ structure and properties.

The microbiota of technosols resembles that of a nearby forest soil three years after their establishment

Technosols can be used to rehabilitate degraded land and reuse wastes. Ideally, these newly formed soils should also fulfil the main soil functions. In this study, initially, we characterized the physicochemical and microbial properties of different formulations and their ingredients (i.e., dirt from a waste recovery plant, recycled bentonite, sewage sludge). When these technosols were then used for the rehabilitation of a quarry, the evolution of such properties was monitored for three consecutive years. Physicochemical and microbial properties were compared to those of a reference soil from a nearby forest. Diversity and composition of prokaryotes and eukaryotes were determined using 16S and 18S rRNA amplicon sequencing. Three years after establishment, as much as 78.8% and 63.9% of the prokaryotic and eukaryotic orders, respectively, were shared between the technosols and the reference forest soil. Although technosols initially showed lower values of CO2 emission, compaction and functional diversity (Biolog EcoPlates™), at the end of the study these values were similar to those observed in the reference forest soil. It was concluded that the microbiota of the studied technosols resembles that of the nearby forest soil after just three years of establishment.

Development of polysaccharide-based mucoadhesive ophthalmic lubricating vehicles: The effect of different polymers on physicochemical properties and functionality

Incorporation of mucoadhesive polymers is one of the first efficient modification of conventional liquid ophthalmic formulations in order to prolong the residence time at ocular surface. The aim of this work was formulation of viscous ophthalmic vehicles/ocular lubricants containing derivative of guar gum, chitosan and cellulose derivatives (hypromellose and hydroxyethylcellulose) alone or in combination. Optimized formulations were developed by choosing appropriate polymer or combination of polymers in suitable concentrations with adequate physicochemical, rheological and mucoadhesive properties. Influence of the addition of simulated tear fluid, steam sterilization and storage on clarity, pH value and rheological properties of different formulations were evaluated. The compounded vehicles were compared with commercially available ocular lubricants containing similar polymers. It was observed that viscosities of commercially available eye drops were above the optimal viscosity range. The mucoadhesive potential of the vehicles, rheological synergism and type of polymer-mucin interaction were determined. Combination of chitosan and guar gum exhibited optimal physicochemical, rheological and mucoadhesive properties and had a potential for the longest retention time in tear film. Considering the simplicity of its preparation and stability (over a period of one-month storage), this vehicle could be used for extemporaneously compounded ocular preparations for specific needs of individual patients.

Abstract ID: 94 Development of a methodology for formulating radiologically equivalent materials to human tissues

The study and development of phantom materials is central to the calculation of patient doses in medical imaging applications. To ensure tissue-equivalence, these materials should have radiation attenuation and scattering properties similar to water or human tissues [ 1 Hermanm K.P. et al. Phys Med Biol. 1985; 30: 1195-1200 Crossref PubMed Scopus (43) Google Scholar , 2 Homolka et al. Phys Med Biol. 2002; 47: 2907-2916 Crossref PubMed Scopus (15) Google Scholar , 3 White D. R Phys Med Biol. 1977; 22: 219-228 Crossref PubMed Scopus (81) Google Scholar ]. Additionally, Monte Carlo techniques are useful to evaluate the radiation transmission and scattering properties of different formulations in order to assure their tissue equivalence when compared with real tissues. In this work the authors evaluate the use of the least squares method as a tool to optimize the formulation of phantom materials. There were developed water-equivalent materials for diagnostic imaging energy range (10–150 keV) as well as mammography phantom formulations for different glandular/adipose breast tissue compositions [ [4] Hammerstein et al. Radiol V. 1979; 130: 485-491 Crossref PubMed Scopus (489) Google Scholar ] for the energy range 8–28 keV. The developed materials are constituted by a thermoplastic base and some additives. The methodology consisted in fitting by the Least Square Method the volume fractions of the components of the phantom material in order to make their linear attenuation coefficient [ [5] Hubbel J.H. Seltzer S.M. 2004, Available:http://physics.nist.gov/xaamdi. Google Scholar ] as close as possible to the linear attenuation coefficient of the reference material such as breast tissue or water. A weight function which reflects the contribution of the X-ray spectra in the suitable energy range was also introduced. The weight function used represents the standard radiation spectra qualities RQR10 and RQR-M2 according to TRS 457 (IAEA) [ [6] IAEA TRS 457 Vienna. 2011. Google Scholar ]. The transmitted and scattered X-ray spectra of the developed compositions were simulated as well as their dose profiles using the PENELOPE Monte Carlo code. The linear attenuation coefficient obtained using the least squares method is in good agreement with the reference material for both water and breast tissue with relative differences lower than 2%. The Monte Carlo method is very useful in determining the X-ray transmission and scattering properties of the materials, before the manufacture of the physical phantom. The study and development of phantom materials is central to the calculation of patient doses in medical imaging applications. To ensure tissue-equivalence, these materials should have radiation attenuation and scattering properties similar to water or human tissues [ 1 Hermanm K.P. et al. Phys Med Biol. 1985; 30: 1195-1200 Crossref PubMed Scopus (43) Google Scholar , 2 Homolka et al. Phys Med Biol. 2002; 47: 2907-2916 Crossref PubMed Scopus (15) Google Scholar , 3 White D. R Phys Med Biol. 1977; 22: 219-228 Crossref PubMed Scopus (81) Google Scholar ]. Additionally, Monte Carlo techniques are useful to evaluate the radiation transmission and scattering properties of different formulations in order to assure their tissue equivalence when compared with real tissues. In this work the authors evaluate the use of the least squares method as a tool to optimize the formulation of phantom materials. There were developed water-equivalent materials for diagnostic imaging energy range (10–150 keV) as well as mammography phantom formulations for different glandular/adipose breast tissue compositions [ [4] Hammerstein et al. Radiol V. 1979; 130: 485-491 Crossref PubMed Scopus (489) Google Scholar ] for the energy range 8–28 keV. The developed materials are constituted by a thermoplastic base and some additives. The methodology consisted in fitting by the Least Square Method the volume fractions of the components of the phantom material in order to make their linear attenuation coefficient [ [5] Hubbel J.H. Seltzer S.M. 2004, Available:http://physics.nist.gov/xaamdi. Google Scholar ] as close as possible to the linear attenuation coefficient of the reference material such as breast tissue or water. A weight function which reflects the contribution of the X-ray spectra in the suitable energy range was also introduced. The weight function used represents the standard radiation spectra qualities RQR10 and RQR-M2 according to TRS 457 (IAEA) [ [6] IAEA TRS 457 Vienna. 2011. Google Scholar ]. The transmitted and scattered X-ray spectra of the developed compositions were simulated as well as their dose profiles using the PENELOPE Monte Carlo code. The linear attenuation coefficient obtained using the least squares method is in good agreement with the reference material for both water and breast tissue with relative differences lower than 2%. The Monte Carlo method is very useful in determining the X-ray transmission and scattering properties of the materials, before the manufacture of the physical phantom.

Enhancement of solubility and oral bioavailability of manidipine by formation of ternary solid dispersion with d-α-tocopherol polyethylene glycol 1000 succinate and copovidone

Context: Low bioavailability of oral manidipine (MDP) is due to its low water solubility.Objective: The objective of this study was to increase the solubility and bioavailability of MDP by fabricating ternary solid dispersion (tSD) with d-α-tocopherol polyethyleneglycol-1000-succinate and copovidone.Methods: In this study, solid ternary phase diagram was applied in order to check the homogeneity of tSD prepared by melting and solidifying with dry ice. The physicochemical properties of different formulations were determined by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR) and hot stage microscopy. Their solubility, dissolution, stability and bioavailability were also investigated.Results and discussion: The results demonstrated that tSD obtained from ternary phase diagram divided into homogeneous and non-homogeneous regions. In the homogenous region, the transparent characteristics of tSD was observed and considered as a glass solution, which have a higher MDP solubility than that in non-homogenous region. The hot stage microscopy, DSC and PXRD confirmed that solid dispersion was formed in which MDP was molecularly dispersed in the carriers, especially in the homogenous region of phase diagram. FTIR analysis demonstrated strong hydrogen bonding between amine groups of MDP and carbonyl groups of copovidone, which supported a higher solubility and dissolution of tSD. The pharmacokinetic study in Wistar rats showed that the tSD had the greatest effect on oral bioavailability. Immediate hypotensive effect of tSD was also observed in vivo.Conclusions: The improvement of stability, dissolution and oral bioavailability of MDP could be achieved by using tSD technique.

Preparation and Properties of Blue Edible Inkjet Ink Based on Chitosan Oligochitosan

Different formulations of blue edible inkjet inks were prepared in this study using chitosan oligochitosan as a binder. The properties of different formulations of the ink were analysed by measuring conductivity, surface tension, viscosity, and antimicrobial properties. Chromaticity and density experiments were also conducted on the blue inkjet inks. Results show that the quality of the printed matter was improved considerably, including enhanced resolution, antimicrobial resistance, and reduced graphic burrs, after the addition of chitosan oligosaccharide.

Development of Floating-Mucoadhesive Microsphere for Site Specific Release of Metronidazole.

The purpose of this study was to develop and evaluate metronidazole loaded floating-mucoadhesive microsphere for sustained drug release at the gastric mucosa. Alginate gastroretentive microspheres containing metronidazole were prepared by ionic gelation method using sodium bicarbonate as gas forming agent, guar gum as mucoadhesive polymer, and Eudragit L100 as drug release modifier. Carbopol was used for increasing the bead strength. The microspheres were characterized by scanning electron microscopy and evaluated by means of drug entrapment efficiency, in vitro buoyancy, and swelling studies. In vitro mucoadhesion and drug release studies were carried out in order to evaluate site specific sustained drug release. All formulations showed 100% buoyancy in vitro for a prolonged period of time. Amount of guar gum influenced the properties of different formulations. The formulation containing drug and guar gum at a ratio of 1:0.5 showed the best results with 76.3% drug entrapment efficiency, 61.21% mucoadhesion, and sustained drug release. Carbopol was found to increase surface smoothness of the microspheres. Metronidazole mucoadhesive-floating microspheres can be effectively used for sustained drug release to the gastric mucosa in treatment of upper GIT infection.

An explicit large time step particle-in-cell scheme for nonlinear gyrokinetic simulations in the electromagnetic regime

A new algorithm for electromagnetic gyrokinetic simulations, the so called “pullback transformation scheme” proposed by Mishchenko et al. [Phys. Plasmas 21, 092110 (2014)] is motivated as an explicit time integrator reset after each full timestep and investigated in detail. Using a numerical dispersion relation valid in slab geometry, it is shown that the linear properties of the scheme are comparable to those of an implicit v∥-scheme. A nonlinear extension of the mixed variable formulation, derived consistently from a field Lagrangian, is proposed. The scheme shows excellent numerical properties with a low statistical noise level and a large time step especially for MHD modes. The example of a nonlinear slab tearing mode simulation is used to illustrate the properties of different formulations of the physical model equations.

In situ polymerization of ε-caprolactam in the presence of polyester polyol and nanosilica toward amorphous polyamide6/SiO2 nanocomposite

Amorphous polyamide6/fumed silica nanocomposites are a new class of polyamides with improved barrier properties. Recently, polymer/fumed silica nanocomposites have received much attention due to the benefits of strongly improved physical, mechanical and chemical properties compared to the pure polymer. In this study, an amorphous nanocomposite of polyamide6 was prepared via in situ polymerization of e-caprolactam as a monomer, sodium caprolactam as a catalyst, polyester polyol as a comonomer, toluene diisocyanate as an activator and fumed silica as nanoparticles. Effects of different concentrations of polyester polyol and fumed silica on the formation of nanocomposites and their crystallization, gas permeability and dynamic mechanical properties were investigated in comparison with those of the pure nylon6. Physical and mechanical properties of different formulations which prepared via reactive melt blending were determined using dynamic mechanical thermal analysis, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy and atomic force microscopy techniques. Barrier properties against oxygen and water absorption were examined, as well. Results showed that addition of 4.96 wt% catalyst, 7 wt% activator, 1 wt% polyester polyol and 3 wt% fumed silica led to the best permeability properties.

Rheological and textural properties of different formulations for functional rice based biscuits

Rheological and textural properties of different formulations for functional rice based biscuits

Niosomal carriers enhance oral bioavailability of carvedilol: effects of bile salt-enriched vesicles and carrier surface charge.

Carvedilol (CRV) is an antihypertensive drug with both alpha and beta receptor blocking activity used to preclude angina and cardiac arrhythmias. To overcome the low, variable oral bioavailability of CRV, niosomal formulations were prepared and characterized: plain niosomes (without bile salts), bile salt-enriched niosomes (bilosomes containing various percentages of sodium cholate or sodium taurocholate), and charged niosomes (negative, containing dicetyl phosphate and positive, containing hexadecyl trimethyl ammonium bromide). All formulations were characterized in terms of encapsulation efficiency, size, zeta potential, release profile, stability, and morphology. Various formulations were administered orally to ten groups of Wistar rats (n=6 per group). The plasma levels of CRV were measured by a validated high-performance liquid chromatography (HPLC) method and pharmacokinetic properties of different formulations were characterized. Contribution of lymphatic transport to the oral bioavailability of niosomes was also investigated using a chylomicron flow-blocking approach. Of the bile salt-enriched vesicles examined, bilosomes containing 20% sodium cholate (F2) and 30% sodium taurocholate (F5) appeared to give the greatest enhancement of intestinal absorption. The relative bioavailability of F2 and F5 formulations to the suspension was estimated to be 1.84 and 1.64, respectively. With regard to charged niosomes, the peak plasma concentrations (Cmax) of CRV for positively (F7) and negatively charged formulations (F10) were approximately 2.3- and 1.7-fold higher than after a suspension. Bioavailability studies also revealed a significant increase in extent of drug absorption from charged vesicles. Tissue histology revealed no signs of inflammation or damage. The study proved that the type and concentration of bile salts as well as carrier surface charge had great influences on oral bioavailability of niosomes. Blocking the lymphatic absorption pathway significantly reduced oral bioavailability of CRV niosomes. Overall twofold enhancement in bioavailability in comparison with drug suspension confers the potential of niosomes as suitable carriers for improved oral delivery of CRV.