scholarly journals Dual-Responsive Nanotubes Assembled by Amphiphilic Dendrimers: Controlled Release and Crosslinking

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3479
Author(s):  
Minghui Zhang ◽  
Hui Yang ◽  
Jiazhong Wu ◽  
Siyu Yang ◽  
Danfeng Yu ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Self Assembly ◽  
Crosslinking Agent ◽  
Halloysite Nanotubes ◽  
Release Time ◽  
Layer By Layer ◽  
Stimuli Responsive ◽  
Simple Strategy ◽  
Profile Control ◽  
Amphiphilic Dendrimers

Although stimuli-responsive release systems have attracted great attention in medical applications, there has been no attempt at “precise” deep profile control based on such systems, which is greatly need to improve oil recovery. With this in mind, we provided a facile and simple strategy to prepare stimuli-responsive composite capsules of amphiphilic dendrimers–poly(styrene sulfonic acid) sodium/halloysite nanotubes (HNTs) via layer-by-layer (LbL) self-assembly technique, controlling the release crosslinking agent methenamine under different pH or salinity conditions. The release time of methenamine encapsulated in multilayer shells is about 40 h, which can be prolonged with the introduction of salt or shortened via the addition of acid, which accordingly induces the gelation of polyacrylamide (PAM) solutions, taking from a few hours to a dozen days. This study provided a novel approach for controllable release of chemical agents and controllable crosslinking of deep profiles in many application fields.

scholarly journals Carbon Nano-Onions Reinforced Multilayered Thin Film System for Stimuli-Responsive Drug Release

Pharmaceutics ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 1208
Author(s):  
Narsimha Mamidi ◽  
Ramiro Velasco Delgadillo ◽  
Aldo Gonzáles Ortiz ◽  
Enrique Barrera
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Drug Release ◽  
Self Assembly ◽  
Critical Role ◽  
Layer By Layer ◽  
Film System ◽  
Stimuli Responsive ◽  
Ph Responsive ◽  
Thin Film System

Herein, poly (N-(4-aminophenyl) methacrylamide))-carbon nano-onions (PAPMA-CNOs = f-CNOs) and anilinated-poly (ether ether ketone) (AN-PEEK) have synthesized, and AN-PEEK/f-CNOs composite thin films were primed via layer-by-layer (LbL) self-assembly for stimuli-responsive drug release. The obtained thin films exhibited pH-responsive drug release in a controlled manner; pH 4.5 = 99.2% and pH 6.5 = 59.3% of doxorubicin (DOX) release was observed over 15 days. Supramolecular π-π stacking interactions between f-CNOs and DOX played a critical role in controlling drug release from thin films. Cell viability was studied with human osteoblast cells and augmented viability was perceived. Moreover, the thin films presented 891.4 ± 8.2 MPa of the tensile strength (σult), 43.2 ± 1.1 GPa of Young’s modulus (E), and 164.5 ± 1.7 Jg−1 of toughness (K). Quantitative scrutiny revealed that the well-ordered aligned nanofibers provide critical interphase, and this could be responsible for augmented tensile properties. Nonetheless, a pH-responsive and mechanically robust biocompatible thin-film system may show potential applications in the biomedical field.

Synthesis and Self‐Assembly of Stimuli‐Responsive Amphiphilic Dendrimers

2021 ◽  
pp. 2100212
Author(s):  
Sayun Myung ◽  
Gwang Mo Kim ◽  
Hyeongju Noh ◽  
Ho‐Joong Kim ◽  
Si Kyung Yang
Keyword(s):  
Self Assembly ◽  
Stimuli Responsive ◽  
Amphiphilic Dendrimers

Experimental Study on High Temperature-Resistant Gel for Profile Control

2015 ◽  
Vol 733 ◽  
pp. 165-168 ◽  
Author(s):  
Shao Bin Hu ◽  
Peng Wang ◽  
Chang Liang Chen ◽  
Shao Ke Liu ◽  
Zhe Wang
Keyword(s):  
High Temperature ◽  
Oil Recovery ◽  
Volume Fraction ◽  
Crosslinking Agent ◽  
Reservoir Water ◽  
Good Thermal Stability ◽  
Heat Stabilizer ◽  
Profile Control ◽  
Weak Gel ◽  
Gel System

In order to control water and increase oil recovery in reservoir of high temperature (120°C), experiments were carried out to study the impacts of dosage of HPAM, crosslinking agent, delayed crosslinking agent and heat stabilizer on the properties of gel system, and a high temperature-resistant movable weak gel profile control system was presented, whose formula is 2.0g/L HPAM + 0.2% (volume fraction) crosslinking agent + 0.1g/L delayed crosslinking agent + 0.1g/L heat stabilizer. This gel system has good thermal stability at 120°C. It has good flow properties before gelation, and can effectively enter larger pores. After gelation, its viscosity increases so significantly that it can be stranded and the larger pores can be plugged. The plugging rate can be over 93%. Thus, subsequent fluid injection can be redirected into the low-permeability layers, effectively improving the reservoir water absorption profile and oil recovery.

The Experimental Research on Combining Binary Compound Flooding and Profile Control Technology to Improve Recovery Efficiency

2014 ◽  
Vol 881-883 ◽  
pp. 1691-1695
Author(s):  
Shao Ning Yuan ◽  
Guang Sheng Cao ◽  
Xiao Wei Duan
Keyword(s):  
Oil Recovery ◽  
Crosslinking Agent ◽  
Oil Production ◽  
Binary Compound ◽  
Compound System ◽  
Production Plant ◽  
Control Technology ◽  
Displacement Effect ◽  
Parallel Displacement ◽  
Profile Control

With the using of binary compound flooding in Jinzhou oil production plant of Liaohe Oilfield, problems like interwell interporosity flow and the unsatisfactory displacement effect occurs. The EOR method of combination of binary compound flooding and profile control technology has been adopted to solve these problems. The JSY crosslinking agent has been selected which has good compatibility with binary compound system by means of experiment of gel strength and gel time. And the formula system of binary compound flooding profile control which can improve the displacement effect of Jinzhou oil production plant has been formed after concentration optimization aim at improving oil recovery. The laboratory core plugging experiments show that the system of binary compound flooding profile control behaves better plugging effect and its plugging rate was greater than 94%. The parallel displacement experiments on low, medium and high permeability cores show that the oil recovery of binary compound flooding profile control system, which can improve the oil recovery more effectively, enhanced about 12% of oil recovery than binary compound flooding.

Preparation and Performance Evaluation of Alkali-resistant Gel-type Deep Profile Agent

2016 ◽  
Vol 9 (1) ◽  
pp. 21-27 ◽  
Author(s):  
Yazhou Zhou ◽  
Daiyin Yin
Keyword(s):  
Performance Evaluation ◽  
Oil Recovery ◽  
Crosslinking Agent ◽  
Gelation Time ◽  
Alkaline Condition ◽  
Good Effect ◽  
Chemical Agent ◽  
Asp Flooding ◽  
Profile Control ◽  
Deep Profile

Currently, most profile control agents would be degraded in strong alkaline condition. They could not be applied in ASP (alkaline, surfactant and partially hydrolyzed polyacrylamide) flooding. To solve this problem, a new kind of alkali-resistant gel for deep profile has been studied. Based on the profile control mechanism of profile agent and the crosslinking mechanism of the polymer, the selection of the chemical agent with different type and concentration was carried out in strong alkaline (pH=12), using ordinary polymer as the main agent, organic and inorganic chemical crosslinking agent. The performance evaluation, residual resistance factor and displacement experiment for the prepared profile agent were carried out. The results show that the profile agent weakly affected the interfacial tension of the ASP flooding. The gelation time could be tuned by adjusting the concentration of the delayed coagulant. The alkali-resistant profile agent with good plugging performance was suitable for deep profile control. When this profile agent was applied in the process of ASP flooding, it could adjust the liquid producing profile and improve the oil displacement efficiency, the recovery ratio was about 4% higher than ASP flooding. The field test of alkali-resistant gel-type profile agent shows that, this alkali-resistant profile agent can achieve good effect, it can enhance oil recovery by 3%.

Smart Polymers and their Applications: A Review

2017 ◽  
Vol 8 (03) ◽  
Author(s):  
Gore S. A. ◽  
Gholve S. B. ◽  
Savalsure S. M. ◽  
Ghodake K. B. ◽  
Bhusnure O. G. ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Water Soluble ◽  
Solution Temperature ◽  
Smart Polymers ◽  
Stimuli Responsive ◽  
Responsive Materials ◽  
Water Soluble Polymers ◽  
Commercial Applications ◽  
Stimuli Sensitive ◽  
External Stimuli

Smart polymers are materials that respond to small external stimuli. These are also referred as stimuli responsive materials or intelligent materials. Smart polymers that can exhibit stimuli-sensitive properties are becoming important in many commercial applications. These polymers can change shape, strength and pore size based on external factors such as temperature, pH and stress. The stimuli include salt, UV irradiation, temperature, pH, magnetic or electric field, ionic factors etc. Smart polymers are very promising applicants in drug delivery, tissue engineering, cell culture, gene carriers, textile engineering, oil recovery, radioactive wastage and protein purification. The study is focused on the entire features of smart polymers and their most recent and relevant applications. Water soluble polymers with tunable lower critical solution temperature (LCST) are of increasing interest for biological applications such as cell patterning, smart drug release, DNA sequencing etc.

Sticky ends in a self-assembling ABA triblock copolymer: the role of ureas in stimuli-responsive hydrogels

2019 ◽  
Vol 4 (1) ◽  
pp. 91-102 ◽  
Author(s):  
Ryan T. Shafranek ◽  
Joel D. Leger ◽  
Song Zhang ◽  
Munira Khalil ◽  
Xiaodan Gu ◽  
...  
Keyword(s):  
Self Assembly ◽  
Viscoelastic Properties ◽  
Triblock Copolymer ◽  
Thermal Response ◽  
Stimuli Responsive ◽  
Self Assembling ◽  
Polymeric Hydrogels ◽  
Aba Triblock Copolymer ◽  
Responsive Hydrogels

Directed self-assembly in polymeric hydrogels allows tunability of thermal response and viscoelastic properties.

scholarly journals Construction of Chitosan/Alginate Nano-Drug Delivery System for Improving Dextran Sodium Sulfate-Induced Colitis in Mice

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1884
Author(s):  
Mengfei Jin ◽  
Shangyong Li ◽  
Yanhong Wu ◽  
Dandan Li ◽  
Yantao Han
Keyword(s):  
Self Assembly ◽  
Average Diameter ◽  
Mucosal Healing ◽  
Plga Nanoparticles ◽  
Narrow Particle Size Distribution ◽  
Layer By Layer ◽  
Systemic Side Effects ◽  
Assembly Technology ◽  
The Fourier Transform ◽  
Polyelectrolyte Film

(1) Background: In the treatment of ulcerative colitis (UC), accurate delivery and release of anti-inflammatory drugs to the site of inflammation can reduce systemic side effects. (2) Methods: We took advantage of this goal to prepare resveratrol-loaded PLGA nanoparticles (RES-PCAC-NPs) by emulsification solvent volatilization. After layer-by-layer self-assembly technology, we deposited chitosan and alginate to form a three-layer polyelectrolyte film. (3) Results: It can transport nanoparticles through the gastric environment to target inflammation sites and slowly release drugs at a specific pH. The resulting RES-PCAC-NPs have an ideal average diameter (~255 nm), a narrow particle size distribution and a positively charged surface charge (~13.5 mV). The Fourier transform infrared spectroscopy showed that resveratrol was successfully encapsulated into PCAC nanoparticles, and the encapsulation efficiency reached 87.26%. In addition, fluorescence imaging showed that RES-PCAC-NPs with positive charges on the surface can effectively target and accumulate in the inflammation site while continuing to penetrate downward to promote mucosal healing. Importantly, oral RES-PCAC-NPs treatment in DSS-induced mice was superior to other results in significantly improved inflammatory markers of UC. (4) Conclusions: Our results strongly prove that RES-PCAC-NPs can target the inflamed colon for maximum efficacy, and this oral pharmaceutical formulation can represent a promising formulation in the treatment of UC.

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