Hot Dispersion Research Articles

Systematic Development of Hot Melt Extrusion-Based Amorphous Solid Dispersion: Integrating Quality by Design and In Silico Modeling

Systematic Development of Hot Melt Extrusion-Based Amorphous Solid Dispersion: Integrating Quality by Design and In Silico Modeling

Spatio-temporal variations of ecosystem service value and its spatial heterogeneity mechanism in the Dongjiang River Basin, China.

Comprehensive and deep research on the variations of ecosystem service value (ESV) based on land utilization/land cover change from a spatio-temporal perspective is of great significance for regional ecosystem optimization, as well as coordinated sustainable development of natural environment and economic society. Based on land utilization, natural environment, and socio-economic data of Dongjiang River Basin from 2010 to 2020, combined with hotspot analysis tools and local spatial autocorrelation analysis methods, we comprehensively analyzed the spatio-temporal variations of Dongjiang River Basin ESV, and further explored the spatial differentiation mechanism with geographic detector tools. The results showed that Dongjiang River Basin was dominated by forest ecosystem from 2010 to 2020. The construction land area had expanded significantly mainly from arable land and forest. The Dongjiang River Basin ESV showed a downward and then an upward trend. The ESV of arable land, forest and construction land continuously decreased, and the ESV of water decreased first and then increased substantially. The spatial distribution of ESV hot and cold spots had a significant agglomeration effect, presenting a pattern of hot spot dispersion in the upstream area and cold spots aggregation in the downstream area. The ESV distribution in the upstream and downstream area was not balanced, with the downstream area bearing greater ecological stress. According to the detection results of ESV spatial differentiation mechanism, land utilization was the main factor affecting the spatial differentiation, with the spatial difference of ESV (q value) reaching 0.462. The interaction of factors could greatly strengthen the spatial differentiation effect on Dongjiang River Basin ESV.

Performance evaluation of different cationic surfactants as anti-swelling agents for shale formations

In this study, three different novel cationic surfactants decyl-trimethyl-ammonium bromide (S1), Octyl-trimethyl-ammonium bromide (S2), hexyl-trimethyl-ammonium bromide (S3) were used to formulate water-based drilling formulations to comprehend the interactions between drilling fluids components and with wellbore formations. The modified drilling formulations were prepared by incorporating novel surfactants in the base mud along with other additives such as bentonite, PAL-C, xanthan gum, and barite. The effect of the surfactant's chemical structure was assessed by rheology and filtration experiments, and colloidal dispersion stability was determined by particle size distribution analysis and sedimentation tests. The shale swelling inhibition characteristics of surfactant-based formulations were accessed by hot rolling dispersion tests, linear swelling rates, and capillary suction time tests. The performance of surfactant-based formulations for shale swelling inhibition was compared with KCl-based and conventionally used base mud formulations. The surface wettability of shale in the presence of different formulations was assessed by a high-resolution optical tensiometer. Shale inhibition properties of surfactant-based formulations depict that shale dispersion recovery increased to 98% for BS1 formulation compared to all other used formulations. Linear swelling of shale pellet show that the swelling rate of BS1 formulation was only 13% compared to all other formulations. The contact angle experiments showed that the BS1 formulation increased the contact angle of a water droplet and reduced the wettability of drilling fluids. The experimental results showed that S1 surfactant has enhanced shale inhibition characteristics compared to other surfactants and conventionally used shale inhibitors.

Mo–Ni, Mo–Fe and Mo–Ni–W nanoparticles for down-hole upgrading

Patented in situ (in reservoir) upgrading technology (ISUT) converts a portion of the reservoir into a “catalytic reactor” by irreversibly attaching a low percentage of nanoparticles to the reservoir's sand/rock. The nanoparticles are prepared as a dispersion in hot vacuum residue and the hot dispersion is injected into the reservoir with low quantities of hydrogen.MoNi, MoFe and MoNiW nanoparticles suspended in bitumen were prepared, in similar way as in ISUT, and the suspensions treated in a batch reactor. Two different sulfiding agents (ammonium sulfide and thiocarbamide) were added during the preparation of the nanoparticles-bitumen suspension. Particle diameters obtained for the suspensions were determined by NTA. The particles were recovered after reaction and its surface composition determined by XPS. Reaction products were analyzed by high temperature simulated distillation, density, viscosity, sulfur and nitrogen content and stability (P-value). MoNi, MoFe and MoNiW with average sizes of 84, 101 and 93 nm, respectively, were produced. XPS characterization of the Mo–Ni–W particles before reaction showed that Mo and Ni are only partly sulfided, while W was present as WO3. The proportion of the metals in the sulfided state increases after reaction from 39 to 94, 35 to 77 and a 0 to 50 (atomic %) for Mo, Ni and W, respectively. In addition, VR conversions were similar by comparing the thermal and catalytic tests, indicating that VR cracking is mainly thermal. However, viscosity, MCR and S contents were lower, and API gravity was higher when a catalyst was used. Also, catalytic products proved more stable than products obtained from thermal reaction. The reaction carried out using dispersions where thiocarbamide was the sulfiding agent provided products with slightly betterer properties in spite of showing larger particle diameters.

An Detailed Overview on Mouth Dissolving Film

The present review aims to enlighten about a potential dosage form that is mouth dissolving films. Mouth dissolving film is a rapidly dissolving dosage form that dissolves in the mouth within a few seconds without the intake of water and is mainly used for pediatric and geriatric patients due to its flexibility and patient compliance. It is a potential dosage form for drugs having high metabolism and low bioavailability. Solvent casting, hot melt extrusion, solid dispersion, semisolid casting, rolling, and other processes can all be used to create mouth dissolving film, but solvent casting is the most popular due to its consistency and superior physical properties. Mouth dissolving film is evaluated for the following parameters like physical parameters and chemical parameters. The review sums up information on drug delivery by mouth dissolving films as a promising dosage form for delivering drugs to children and elderly patients, as well as information on its formulation considerations, preparation process, and evaluation criteria.
 Keywords: Mouth dissolving film, Buccal film, Improved patient compliance, Standard composition, Method of preparation, Evaluation

Dispersion characteristics of oversized travelling wave tubes of the submillimeter wave range

The possibilities of using oversized slow-wave structures in traveling wave tubes of the submillimeter wave range are investigated. A description of a linear theory developed to analyze the properties of such slow-wave structures is given. The results of the theoretical analysis of the hot dispersion characteristics of oversized diaphragm waveguides at frequencies of 315 and 800 GHz are presented.

BORAY: A ray tracing code for various magnetized plasma configurations

Ray tracing codes are useful to study the electromagnetic wave propagation and absorption in the geometrical optics approximation. In magnetized fusion plasma community, most ray tracing codes assume the plasma density and temperature be functions of the magnetic flux and study waves only inside the last closed flux surface, which are sufficient for the present day tokamak. However, they are difficult to be used for configurations with open magnetic field line plasmas, such as mirror machine and field-reversed-configuration (FRC). We develop a ray tracing code in cylindrical coordinates (r,ϕ,z) to support arbitrary axisymmetric configurations with both closed and open field lines plasmas. For wave propagation, the cold plasma dispersion relation is usually sufficient, and we require the magnetic field B(r,z) and species densities ns0(r,z) profiles as input. For wave absorption, we require a further temperature Ts0(r,z) profile to solve a hot kinetic plasma dispersion relation. In difference to other ray tracing codes which calculate the imaginary part of wave vector k⊥,i for wave absorption, we calculate the imaginary part of wave frequency ωi, which is shown to be equivalent with the former technique under weak damping approximation. The code can use either numerical or analytical equilibrium. Examples and benchmarks with electron cyclotron wave, lower hybrid wave and ion cyclotron wave for tokamak, spherical tokamak (ST), FRC and mirror machine are shown. Program summaryProgram Title: BORAYCPC Library link to program files:https://doi.org/10.17632/tnkrjdbcz8.1Code Ocean capsule:https://codeocean.com/capsule/6205646Licensing provisions: BSD 3-clauseProgramming language: MatlabNature of problem: Solve the plasmas electromagnetic wave propagation and absorption in the geometrical optics approximation for magnetized plasmas based on ray tracing of plasma dispersion relation. In axisymmetric (r,z) coordinates, the code can be used for both closed and open field lines plasmas of various configurations such as tokamak, spherical tokamak, FRC and mirror machine.Solution method: Runge-Kutta time integral to solve ray tracing equations for wave propagation, and integral the imaginary part of the wave frequency in hot kinetic dispersion relation for wave absorption.Additional comments including restrictions and unusual features: Kinetic relativistic effects and collisional damping are not included in the present version yet. Only axisymmetric two-dimensional (2D) profiles are support in present version.

Starch films containing starch nanoparticles as produced in a single step green route

Thermoplastic starch films with glycerol and nanoparticles were prepared from regular cornstarch in a single and quick step using the green chemical principle. Starch nanoparticles (SNPs) were produced by nanoprecipitation with the addition of ethanol as nonsolvent to the hot and room temperature polymeric dispersion. Contact angle increased from 41°, for the control sample, to 67°, for the film produced with glycerol as a plasticizer and by adding alcohol to the hot polymeric dispersion, which indicated a significant decrease in hydrophilicity. SNPs acted as a reinforcing agent and the mechanical properties varied as a function of the presence of plasticizer. Films prepared without glycerol were more rigid presenting the highest Young’s modulus (E = 3640 ± 209 MPa) and the lowest elongation at break (εmax), whereas the films prepared with glycerol were more flexible with the lowest E value and higher εmax around 23%.

An Optimization Procedure for Preparing Aqueous CAR/HP-CD Aggregate Dispersions.

β-Carotene is a very important molecule for human health. It finds a large application in the food industry, especially for the development of functional foods and dietary supplements. However, β-carotene is an unstable compound and is sensitive to light, temperature, and oxygen. To overcome those limitations, various delivery systems were developed. The inclusion of β-carotene by cyclodextrin aggregates is attractive due to non-toxicity, low hygroscopicity, stability, and the inexpensiveness of cyclodextrins. In this study, β-carotene/2-hydroxypropyl-β-cyclodextrin aggregates were prepared based on the procedure of the addition of β-carotene in an organic solvent to the hot water dispersion of 2-hydroxypropyl-β-cyclodextrin and the following instant evaporation of the organic solvent. The best conditions for the aggregate preparation were found to be as follows: 25% concentration of 2-hydroxypropyl-β-cyclodextrin in water, 65 °C temperature, and acetone for β-carotene dissolution. The efficiency of entrapping was equal to 88%. The procedure is attractive due to the short time of the aggregate preparation.

Screening of Selective C16 to C18 Lipids and Process Optimization Based on Design of Experiments in Formulating Solid Lipid Microparticles by Twin Screw Hot Melt Dispersion Process

Screening of Selective C16 to C18 Lipids and Process Optimization Based on Design of Experiments in Formulating Solid Lipid Microparticles by Twin Screw Hot Melt Dispersion Process

Fabrication and evaluation of Lambda-Cyhalothrin nanosuspoemulsion with pH- and temperature-responsive based on polyethylene wax as carrier

Using polyethylene wax (PW) as the coating matrix, the lambda-cyhalothrin-PW nanosuspoemulsion (LC-PW) with a particle size of 80-150nm was prepared through high-speed stirring, hot melt emulsification and ultrasonic dispersion. The formulation and composition of the LC-PW were optimized, the morphology of the LC-PW was analyzed by dynamic light scattering (DLS) and TEM, and the structure of the LC-PW was characterized by UV and IR. The anti-photolysis test showed that LC-PW had a good anti-photolysis performance. Furthermore, LC-PW could sustainably release Lambda-cyhalothrin, which was pH- and temperature dependent. The insecticidal activity analysis in the greenhouse indicated that the toxic strength between LC-PW and LC-SC (lambda-cyhalothrin-suspension concentrate) to Mythimna separata was similar within the same concentration ranges tested, but the insecticidal duration of LC-PW was significantly longer than LC-SC. Thus, the new type of LC-PW with the properties of anti-photolysis and controlled release is suitable for application in the field as a better insecticide.

β-Carotene colouring systems based on solid lipid particles produced by hot melt dispersion

In this work, β-carotene was selected to develop a novel study, namely a food colorant system based on beeswax solid lipid particles obtained by hot melt dispersion. The obtained microparticles were characterized by optical microscopy, scanning electron microscopy, particle size analysis and Fourier Transform Infrared spectroscopy. It was observed that the obtained size can be modulated by using different amounts of emulsifier, as well as the dispersing capability. In a final stage, the obtained particles were tested concerning their colorant power by selecting a food matrix widely appreciated and consumed (mayonnaise). Moreover, the formulation providing the best hue and dispersibility (formulation containing 3% of Tween 80, and β-carotene at 5 mg/25 g of commercial mayonnaise) was analysed along a storage period of 15 days concerning colour, nutritional value and chemical composition. The results pointed out for colour stability and nutritional value maintenance, after 15 days under storage at 6 °C.

CUSTOM DESIGN PERSPECTIVE IN THE PROCESS PARAMETER OPTIMIZATION OF NANO LIPID CARRIERS

Objective: Nanostructured lipid carrier is an emerging lipid-derived delivery system that is rapidly gaining popularity due to the simplicity of the manufacturing technique. The primary task in formulating nanoparticles is to optimize the parameters that are involved in the process. The rationale behind this study is to optimize the process parameters for the preparation of nanostructured lipid carriers. 
 Methods: The optimization of selected techniques hot homogenization with ultra-sonication and melt dispersion technique, was carried out via statistical analysis software JMP version 13 Pro using custom design approaches. Sonication time, homogenization speed, stirring rate, and cooling temperature were selected as factors for hot homogenization. Stirring speed, stirring time, and dilution volume were the factors deliberated for melt dispersion. The impact of these factors on the responses, particle size, and polydispersity index were studied. The nanoparticles were prepared according to the ten experimental runs generated by the design. Based on the responses, the design space and optimum framework were selected. 
 Results: The prediction profiler indicated maximum desirability at 81% and 80% for hot homogenization and melt dispersion respectively. The actual versus predicted plot of particle size indicated a regression coefficient (R2) of 0.98, and a p-value of 0.0001 for hot homogenization and for melt dispersion the corresponding values were 0.95 and 0.0003. For the response polydispersity index, these values were 0.92 and 0.0052 for hot homogenization and 0.90 and 0.0024 for melt dispersion.
 Conclusion: The endorsing results indicated the authenticity of the model in predicting the significant processing parameters for NLC.

Target-triggered hot spot dispersion for cellular biothiol detection via background-free surface-enhanced Raman scattering tags

Abnormal cellular biothiol levels are related to many abnormal physiological processes, including cancer, multidrug resistance and Alzheimer's disease, etc. In this study, the nano-aggregates of the background-free surface-enhanced Raman scattering (SERS) tags were constructed and developed for the intracellular biothiol detection via a target-triggered disaggregation process. The plasmonic nano-tags were prepared by coating gold nanoparticles with a Raman reporter (4-mercaptobenzonitrile, MBN), which exhibits a single strong peak in the cellular Raman silent region (1800−2800 cm−1) that can eliminate the background interference of cells. Interestingly, this reporter is also the host ligand for guest mercury ions. The coordination of mercury/cyano group induce the formation of the pre-aggregates of nano-tags and the formed nano-aggregates allowing strong SERS signals of reporters. Intracellular biothiols show higher affinity to mercury ions than the SERS tags do, which can break the hot spot geometry and redisperse tags by taking away mercury ions from nano-aggregates, which dramatically decreases the SERS signals of reporters previously laid on gold nanoparticles. The developed SERS “turn off” method was used for biothiol detections in normal, cancer, drug-resistant cells, and biothiol dynamics during chemotherapy. The results demonstrate that the drug-resistant cells (MCF-ADR) lie in a higher biothiol level than cancer cells (MCF-7 and HepG2), and the normal cells (LO2) give a lower biothiol concentration compared with cancer cells. Moreover, most cancer cells are more sensitive to doxorubicin compared with the normal ones. This study provides an important strategy in learning the cellular processes that are highly associated with intracellular biothiol level.

A Drilling Liquid to Reduce the Damage Coalbed Methane

A good protection of coalbed methane reservoir can facilitate its exploitation and usage of, cover the shortage of oil and natural gas supply for China, help cut greenhouse gas emissions, phase down environmental pollution and prevent mine accidents from happening. Firstly, damage mechanisms of coalbed methane reservoir in Qinshui basin of Shanxi province were comprehensively analyzed by X-ray diffraction (XRD), Scanning Electron Microscope (SEM), liner swelling test and hot rolling dispersion experiments, thin-section analysis, mercury penetration analysis, wettability measurement and evaluation of sensitivity. Based on this work, pertinent protection counter- measure study were conducted, the surface wettability modifier SLJ-2 and water sensitivity inhibitor SLYZ-1 were selected out, and then drilling fluid for coalbed methane reservoir in Qinshui basin of Shanxi province composed of 0.4%SLJ-2 + 0.5%SLYZ-1 was developed, which has minimal damage to permeability of ingredient under hygrometric state.

Experimental validation of biocompatible nanostructured lipid carriers of sophorolipid: Optimization, characterization and in-vitro evaluation

To date, the potential of sophorolipids (an important class of glycolipids) has been exploited solely as amphipathic molecules but their ability to formulate lipid nanoparticles has never been explored. In this report, for the first time, lipid nanostructures coated with polysorbates (Tweens) were formulated by a hot dispersion method. By varying the amount of lipid, type of surfactant, and alcohol, dilution ratio etc., the formulation was optimized with respect to its stability, which is a central aspect of their potential applications. Their comprehensive physicochemical characterization was done using static and dynamic light scattering (SLS, DLS), small angle neutron scattering (SANS), zeta-potential, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques. Further hemolysis study was conducted to understand the in-vitro cytotoxicity levels of the lipidic nanoparticles prior to its application as a potent drug delivery device for countermanding the problems associated with challenging tuberculosis and leprosy drug-Rifampicin. Attaining high entrapment efficiency and sustained release from the developed carrier, further interaction with bovine serum albumin was investigated, to understand the in-vivo behavior of the nanostructured lipid carriers (NLCs).

Solid lipid Particles as Drug Carriers – Effects of Particle Preparation Methods and Lipid Excipients on Particle Characteristics

Oral delivery of biopharmaceuticals is limited by the absorption barriers in the Gastrointestinal Tract (GIT) such as low permeability across the biological membranes and the enzymatic degradation by proteases. In this study, lipid-based drug delivery systems were proposed to overcome these obstacles. The aim of this study was to evaluate the effect of particle preparation methods and excipients on the characteristics of Solid Lipid Microparticles (SLM) and Solid Lipid Nanoparticles (SLN). Different triglycerides (TG) were used as the major excipients for the SLM and SLN. Insulin was used as the model protein; insulin-phospholipid (PL) was prepared to increase drug lipophilicity and compatibility with lipid excipients. Four methods were used for preparing lipid particles, i.e. a Hot Melting Dispersion (HMD) technique, a Solvent Evaporation (SE) method, a modified Solvent Evaporation (mSE) method and a Spray Drying technique. The lipid particles were evaluated in terms of size, size distribution, surface morphology and drug Entrapment Efficiency (EE). The results suggested that SE method was the most suitable method for preparing insulin-PL loaded Solid Lipid Particles (SLP). No differences were observed when the SLP with a Long Chain Triglyceride (LCT) either a Medium Chain Triglyceride (MCT) in term of size. 70-90% of the lipidified insulin was incorporated in the lipid particles. The preparation methods affected the size and morphology of SLP significantly, and the selection of lipid excipient should be done based on specific application requirements. Furthermore, the use of the lipidified protein was an efficient way to encapsulate protein in lipid carriers.

Orcinol Glucoside Loaded Polymer - Lipid Hybrid Nanostructured Lipid Carriers: Potential Cytotoxic Agents against Gastric, Colon and Hepatoma Carcinoma Cell Lines.

Orcinol glucoside (OG) - loaded nanostructured lipid carrier (NLC), coated with polyethylene glycol-25/55-stearate (PEG-25/55-SA), were explored for delivering OG to improve in vitro cytotoxicity against gastrointestinal tract (GIT), colon and hepatoma carcinoma cell lines. It is being expected that the PEGylated formulations would possess the sustainability in withstanding the adverse physiological extremities like the most significant metabolic activities and phase I / II enzymatic activities in the intestines. NLCs were prepared using tristearin, oleic acid and PEG-25/55-stearate by hot homogenization-ultrasonic dispersion; characterized by DLS, TEM, SEM, AFM, entrapment efficiency and drug loading capacity studies. NLC diameter ranged from 160 to 230nm with negative zeta potential of -8 to -20mV. TEM/SEM and AFM studies suggest spherical and smooth surface morphologies. Differential scanning calorimetry studies reveal the loss of crystallinity when OG was incorporated into the NLC. NLCs showed initial burst release, followed by sustained release of OG. PEG-NLC exhibited superior anticancer activity against GIT and also in hepatoma cancer cell lines. This is the first report demonstrating a practical approach for possible oral delivery of OG in GIT and targeting hepatoma cancer, warranting further in vivo studies for superior management of GIT cancer.

Study on resonant electron cyclotron heating by OSXB double mode conversion at the W7-X stellarator

Abstract Electromagnetic waves potentially have been used to heat overdense nuclear fusion plasmas through a double mode conversion from ordinary to slow extraordinary and finally to Electron Bernstein Wave (EBW) modes, OSXB. This scheme is efficient and has not any plasma density limit of electron cyclotron resonance heating due to cut-off layer. The efficiency of conversion depends on the isotropic launching angles of the microwaves with the plasma parameters. In this article, a two-step mode conversions of OSXB power transmission efficiency affected by the fast extraordinary (FX) loses at upper hybrid frequency are studied. In addition, the kinetic (hot) dispersion relation of a overdense plasma in a full wave analysis of a OSXB in Wendelstein 7X (W7-X) stellarator plasma has been numerically simulated. The influence of plasma dependent parameters such as finite Larmor radius, electron thermal velocity and electron cyclotron frequency are represented.

Laboratory analysis to assess shale stability for the Zubair Formation, Southern Iraq

The Zubair Formation consists of approximately 55% shale, which causes almost 70% of wellbore problems due to incompatibilities between drilling fluids and shale formations. The most common and effective solution to shale instability is through the design and selection of appropriate drilling fluids. Understanding the interaction between drilling fluids and shale has been a challenge due to the complexity of both the physical and chemical variations in shale formations. This paper presents some of the primary laboratory and wellsite testing techniques that are often used by mud engineers to characterize and remediate drilling fluids and shale interactions. Well-preserved core samples retrieved from the Zubair shale formation in Southern Iraq were run through extensive testing to describe the special characterization of the Zubair shale. These characteristics were measured and described, including the structure, texture, mineralogy, and reactivity, using a scanning electron microscope (SEM), a thin-section photograph, X-ray diffraction analysis (XRD) imaging, and cation exchange capacity (CEC) analysis. Moreover, a capillary suction timer (CST), hot rolling dispersion test, bulk hardness test, linear swell meter (LSM), and fracture development test were used to evaluate the stability of shale in the presence of test fluids. The test fluids included fresh water, 20 wt% NaCl brine, 7 wt% KCl brine, and a combination of 7 wt% KCl and 3 vol% glycol. The results illustrated that the Zubair shale is composed mainly (average content of 51.46%) of brittle minerals (i.e., quartz and calcite), along with 43.54% of clay minerals. The predominant clay minerals were kaolinite and illite, with an average content of 48.06% and 34.71%, respectively. In addition, the cation exchange capacity analysis and capillary suction time test indicated that Zubair shale has a low-to-moderate reactivity with drilling fluids. Furthermore, among the fluid systems tested, the best shale inhibition was achieved when the 7 wt% KCl and 3 vol% glycol solution was used. Shale sample analyses methods were used to understand the geologic features of the Zubair shale formations and to achieve a better perspective on the potential interactions of shale formations with drilling fluids. Understanding the properties and responses of shale formations to fluids is a significant step in achieving the chemical clay stabilization objectives. Proper design of drilling fluids, with appropriate mud weight and suitable additives, can lead to substantial cost reduction in drilling operations.