SIMULATION OF VINPOCETINE RELEASE PROCESS FROM MICROCAPSULES WITH HYDROPHOBIC SHELL

Potential short interfering RNAs (siRNA) modulating gene expression have emerged as a novel therapeutic arsenal against a wide range of maladies and disorders containing cancer, viral infections, bacterial ailments and metabolic snags at the molecular level. Nanogel, in the current medicinal era, displayed a comprehensive range of significant drug delivery prospects. Biodegradation, swelling and de-swelling tendency, pHsensitive drug release and thermo-sensitivity are some of the renowned associated benefits of nanogel drug delivery system. Global researches have also showed that nanogel system significantly targets and delivers the biomolecules including DNAs, siRNA, protein, peptides and other biologically active molecules. Biomolecules delivery via nanogel system explored a wide range of pharmaceutical, biomedical engineering and agro-medicinal application. The siRNAs and DNAs delivery plays a vivacious role by addressing the hitches allied with chronic and contemporary therapeutic like generic possession and low constancy. They also incite release kinetics approach from slow-release while mingling to rapid release at the targets will be beneficial as interference RNAs delivery carriers. Therefore, in this research, we focused on the latest improvements in the delivery of siRNA loaded nanogels by enhancing the absorption, stability, sensitivity and combating the hindrances in cellular trafficking and release process.

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Dual Release Model to Evaluate Dissolution Profiles from Swellable Drug Polyelectrolyte Matrices

Current Drug Delivery ◽

10.2174/1567201817666200512093115 ◽

2020 ◽

Vol 17 (6) ◽

pp. 511-522 ◽

Cited By ~ 2

Author(s):

Alicia Graciela Cid ◽

María Verónica Ramírez-Rigo ◽

María Celeste Palena ◽

Elio Emilio Gonzo ◽

Alvaro Federico Jimenez-Kairuz ◽

...

Keyword(s):

Experimental Data ◽

Drug Release ◽

Inflection Point ◽

Release Profile ◽

Experimental Point ◽

Extended Model ◽

Release Process ◽

Proposed Model ◽

Dual Release ◽

Release Model

Background: Mathematical modeling in modified drug release is an important tool that allows predicting the release rate of drugs in their surrounding environment and elucidates the transport mechanisms involved in the process. Objective: The aim of this work was to develop a mathematical model that allows evaluating the release profile of drugs from polymeric carriers in which the swelling phenomenon is present. Methods: Swellable matrices based on ionic complexes of alginic acid or carboxymethylcellulose with ciprofloxacin were prepared and the effect of adding the polymer sodium salt on the swelling process and the drug release was evaluated. Experimental data from the ciprofloxacin release profiles were mathematically adjusted, considering the mechanisms involved in each stage of the release process. Results: A proposed model, named “Dual Release” model, was able to properly fit the experimental data of matrices presenting the swelling phenomenon, characterized by an inflection point in their release profile. This entails applying the extended model of Korsmeyer-Peppas to estimate the percentage of drug released from the first experimental point up to the inflection point and then a model called Lumped until the final time, allowing to adequately represent the complete range of the drug release profile. Different parameters of pharmaceutical relevance were calculated using the proposed model to compare the profiles of the studied matrices. Conclusion: The “Dual Release” model proposed in this article can be used to predict the behavior of complex systems in which different mechanisms are involved in the release process.

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Design and Experiment of Capacitive Micromachined Ultrasonic Transducer Array for High-Frequency Underwater Imaging

Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) ◽

10.2174/2352096513999201026225123 ◽

2020 ◽

Vol 13 ◽

Author(s):

Yuanyu Yu ◽

Jiujiang Wang ◽

Xin Liu ◽

Sio Hang Pun ◽

Weibao Qiu ◽

...

Keyword(s):

Ultrasound Imaging ◽

High Frequency ◽

Ultrasonic Transducer ◽

Center Frequency ◽

Design Parameters ◽

Underwater Imaging ◽

Release Process ◽

Steel Wires ◽

Capacitive Micromachined Ultrasonic Transducer ◽

Frequency Ultrasound

Background:: Ultrasound is widely used in the applications of underwater imaging. Capacitive micromachined ultrasonic transducer (CMUT) is a promising candidate to the traditional piezoelectric ultrasonic transducer. In underwater ultrasound imaging, better resolutions can be achieved with a higher frequency ultrasound. Therefore, a CMUT array for high-frequency ultrasound imaging is proposed in this work. Methods:: Analytical methods are used to calculate the center frequency in water and the pull-in voltage for determining the operating point of CMUT. Finite element method model was developed to finalize the design parameters. The CMUT array was fabricated with a five-mask sacrificial release process. Results:: The CMUT array owned an immersed center frequency of 2.6 MHz with a 6 dB fractional bandwidth of 123 %. The pull-in voltage of the CMUT array was 85 V. An underwater imaging experiment was carried out with the target of three steel wires. Conclusion:: In this study, we have developed CMUT for high-frequency underwater imaging. The experiment showed that the CMUT can detect the steel wires with the diameter of 100 μm and the axial resolution was 0.582 mm, which is close to one wavelength of ultrasound in 2.6 MHz.

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Research on the Ignition Height and Reaction Flame Temperature of PTFE/Al/Si/CuO with Different Mass Ratios of PTFE/Si

Materials ◽

10.3390/ma14133464 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3464

Author(s):

Xuan Zou ◽

Jingyuan Zhou ◽

Xianwen Ran ◽

Yiting Wu ◽

Ping Liu ◽

...

Keyword(s):

Energy Release ◽

High Speed ◽

Flame Temperature ◽

Sintering Process ◽

Release Process ◽

Reactive Material ◽

Temperature Changes ◽

Release Capacity ◽

Mass Ratios ◽

The Relationship

Recent studies have shown that the energy release capacity of Polytetrafluoroethylene (PTFE)/Al with Si, and CuO, respectively, is higher than that of PTFE/Al. PTFE/Al/Si/CuO reactive materials with four proportions of PTFE/Si were designed by the molding–sintering process to study the influence of different PTFE/Si mass ratios on energy release. A drop hammer was selected for igniting the specimens, and the high-speed camera and spectrometer systems were used to record the energy release process and the flame spectrum, respectively. The ignition height of the reactive material was obtained by fitting the relationship between the flame duration and the drop height. It was found that the ignition height of PTFE/Al/Si/CuO containing 20% PTFE/Si is 48.27 cm, which is the lowest compared to the ignition height of other Si/PTFE ratios of PTFE/Al/Si/CuO; the flame temperature was calculated from the flame spectrum. It was found that flame temperature changes little for the same reactive material at different drop heights. Compared with the flame temperature of PTFE/Al/Si/CuO with four mass ratios, it was found that the flame temperature of PTFE/Al/Si/CuO with 20% PTFE/Si is the highest, which is 2589 K. The results show that PTFE/Al/Si/CuO containing 20% PTFE/Si is easier to be ignited and has a stronger temperature destruction effect.

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Distributed Thermal Energy Storage Configuration of an Urban Electric and Heat Integrated Energy System Considering Medium Temperature Characteristics

Energies ◽

10.3390/en14102924 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2924

Author(s):

Wei Wei ◽

Yusong Guo ◽

Kai Hou ◽

Kai Yuan ◽

Yi Song ◽

...

Keyword(s):

Energy Storage ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Internal Heat ◽

Configuration Model ◽

Electric Heater ◽

Heat Network ◽

Release Process ◽

Medium Temperature ◽

Temperature Characteristics

Distributed thermal energy storage (DTES) provides specific opportunities to realize the sustainable and economic operation of urban electric heat integrated energy systems (UEHIES). However, the construction of the theory of the model and the configuration method of thermal storage for distributed application are still challenging. This paper analyzes the heat absorption and release process between the DTES internal heat storage medium and the heat network transfer medium, refines the relationship between heat transfer power and temperature characteristics, and establishes a water thermal energy storage and electric heater phase change thermal energy storage model, considering medium temperature characteristics. Combined with the temperature transmission delay characteristics of a heat network, a two-stage optimal configuration model of DTES for UEHIES is proposed. The results show that considering the temperature characteristics in the configuration method can accurately reflect the performance of DTES, enhance wind power utilization, improve the operation efficiency of energy equipment, and reduce the cost of the system.

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Enhancing the Release Process Yield for CMOS-MEMS Metal Resonators Based on Diffusion-Controlling Structures

2021 IEEE 34th International Conference on Micro Electro Mechanical Systems (MEMS) ◽

10.1109/mems51782.2021.9375197 ◽

2021 ◽

Author(s):

Cheng-En Hsu ◽

Wei-Chang Li

Keyword(s):

Release Process ◽

Process Yield ◽

Cmos Mems

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Evaluation of Operation Safety of Energy Release Process of Liquefied Air Energy Storage System

Energy ◽

10.1016/j.energy.2021.121403 ◽

2021 ◽

pp. 121403

Author(s):

Chang Lu ◽

Qing He ◽

Shuangshuang Cui ◽

Xingping Shi ◽

Dongmei Du ◽

...

Keyword(s):

Energy Storage ◽

Energy Release ◽

Storage System ◽

Energy Storage System ◽

Release Process

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Development of Novel Oral Formulations of Disulfide Antioxidants Based on Porous Silica for Controlled Release of the Drugs

Materials ◽

10.3390/ma14040963 ◽

2021 ◽

Vol 14 (4) ◽

pp. 963

Author(s):

Ekaterina S. Dolinina ◽

Elena V. Parfenyuk

Keyword(s):

Antioxidant Activity ◽

Surface Chemistry ◽

Sol Gel ◽

Porous Silica ◽

The Body ◽

Oral Drug ◽

Therapeutic Concentration ◽

Release Process ◽

Zero Order Kinetics ◽

Long Time

Powerful antioxidant α-lipoic acid (LA) exhibits limited therapeutic efficiency due to its pharmacokinetic properties. Therefore, the purpose of this work was to evaluate the ability of silica-based composites of LA as well as its amide (lipoamide, LM), as new oral drug formulations, to control their release and maintain their therapeutic concentration and antioxidant activity in the body over a long time. The composites synthesized at different sol–gel synthesis pH and based on silica matrixes with various surface chemistry were investigated. The release behavior of the composites in media mimicking pH of digestive fluids (pH 1.6, 6.8, and 7.4) was revealed. The effects of chemical structure of the antioxidants, synthesis pH, surface chemistry of the silica matrixes in the composites as well as the pH of release medium on kinetic parameters of the drug release and mechanisms of the process were discussed. The comparative analysis of the obtained data allowed the determination of the most promising composites. Using these composites, modeling of the release process of the antioxidants in accordance with transit conditions of the drugs in stomach, proximal, and distal parts of small intestine and colon was carried out. The composites exhibited the release close to the zero order kinetics and maintained the therapeutic concentration of the drugs and antioxidant effect in all parts of the intestine for up to 24 h. The obtained results showed that encapsulation of LA and LM in the silica matrixes is a promising way to improve their bioavailability and antioxidant activity.

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Effect of Poly(L-lysine) and Heparin Coatings on the Surface of Polyester-Based Particles on Prednisolone Release and Biocompatibility

Pharmaceutics ◽

10.3390/pharmaceutics13060801 ◽

2021 ◽

Vol 13 (6) ◽

pp. 801

Author(s):

Abdelrahman Mohamed ◽

Viktor Korzhikov-Vlakh ◽

Nan Zhang ◽

André Said ◽

Iuliia Pilipenko ◽

...

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Molecular Diffusion ◽

Corneal Opacity ◽

Testing Strategy ◽

Release Process ◽

Irritation Test ◽

Model Drug ◽

Novel Drug ◽

Permeability Assay

A plethora of micro- and nanoparticle types are currently investigated for advanced ocular treatment due to improved drug retention times, higher bioavailability and better biocompatibility. Yet, comparative studies of both physicochemical and toxicological performance of these novel drug delivery systems are still rare. Herein, poly(L-lactic acid)- and poly(ε-caprolactone)-based micro- and nanoparticles were loaded with prednisolone as a model drug. The physicochemical properties of the particles were varied with respect to their hydrophilicity and size as well as their charge and the effect on prednisolone release was evaluated. The particle biocompatibility was assessed by a two-tier testing strategy, combining the EpiOcularTM eye irritation test and bovine corneal opacity and permeability assay. The biodegradable polyelectrolyte corona on the particles’ surface determined the surface charge and the release rate, enabling prednisolone release for at least 30 days. Thereby, the prednisolone release process was mainly governed by molecular diffusion. Finally, the developed particle formulations were found to be nontoxic in the tested range of concentrations.

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