Dynamic Characterization and Drug Release of Thermosensitive Poly(N, N-Diethylacrylamide-Co-Itaconic Acid) Copolymer Hydrogels

2011 ◽  
Vol 117-119 ◽  
pp. 1239-1242
Author(s):  
Xiao Qi Li ◽  
Nei Yan Zhang ◽  
Yue Guo Shen
Keyword(s):  
Itaconic Acid ◽  
Monomer Concentration ◽  
Drug Carriers ◽  
Molar Ratio ◽  
Solution Temperature ◽  
Acid Copolymer ◽  
Total Monomer Concentration ◽  
Model Drug ◽  
Equilibrium Swelling Ratio ◽  
Mechanical Performances

In this study, poly(N,N-diethylacrylamide-co-itaconic acid) (P(DEA-co-IA)) copolymer hydrogels were synthesized by changing the initial DEA/IA molar ratio, N,N-methylenebisacrylamide and total monomer concentration. The thermo-sensitive and mechanical performances were optimized by altering the above parameters. In comparison with the PDEA hydrogel, the equilibrium swelling ratio (ESR) and lower critical solution temperature (LCST) of the hydrogels changed with the alternation of the above parameters. The swelling and deswelling kinetics was also studied in dital. The release behaviors of the model drug, aminophylline, are found dependent on hydrogel composition and environmental temperature, which suggests that these materials have potential application as intelligent drug carriers.

Preparation and Swelling Dynamics Characterization of Poly(N, N-Diethylacrylamide-Co-Itaconic Acid) Intelligent Hydrogels

2012 ◽  
Vol 490-495 ◽  
pp. 3382-3386
Author(s):  
Xiao Qi Li ◽  
Nai Yan Zhang ◽  
Jun Hai Zhang
Keyword(s):  
Itaconic Acid ◽  
Monomer Concentration ◽  
Molar Ratio ◽  
Solution Temperature ◽  
Temperature Changes ◽  
Different Temperatures ◽  
Total Monomer Concentration ◽  
Equilibrium Swelling Ratio ◽  
Composition Ratios ◽  
Response To Temperature

Poly(N,N-diethylacrylamide) (PDEA) hydrogel is known for their intelligent reversible swelling/deswelling behavior in response to temperature changes across a lower critical solution temperature (LCST) at around 31oC. In this study, itaconic acid (IA) was co-polymerized with N, N-diethylacrylamide (DEA) monomer to improve the swelling behavior and the total absorbing water. These copolymer hydrogels were prepared by changing the initial DEA/IA molar ratio and total monomer concentration. The chemical structure of hydrogels was characterized by fourier transform infrared (FTIR) spectroscopy. In comparison with the PDEA hydrogel, the equilibrium swelling ratio (ESR) of the hydrogels increase with the increase of IA content in the feed and the swelling dynamics behaviors of the different composition ratios of the P(DEA-co-IA) hydrogels on the different temperatures was investigated in detail.

Synthesis and Deswelling Behavior of Intelligent Thermosensitive Poly(N, N-Diethylacrylamide-Co-Itaconic Acid) Hydrogels

2012 ◽  
Vol 490-495 ◽  
pp. 3667-3671 ◽  
Author(s):  
Nai Yan Zhang ◽  
Yue Guo Shen ◽  
Xiao Qi Li
Keyword(s):  
Itaconic Acid ◽  
Monomer Concentration ◽  
Molar Ratio ◽  
Solution Temperature ◽  
External Temperature ◽  
Critical Solution Temperature ◽  
Different Temperatures ◽  
Total Monomer Concentration ◽  
Equilibrium Swelling Ratio ◽  
Composition Ratios

Poly(N,N-diethylacrylamide) (PDEA) hydrogels possess a lower critical solution temperature (LCST) at around 31oC. When the external temperature is raised above the LCST, the hydrogels experience abrupt and drastic shrinkage. This unique property makes them very useful for biomedical applications such as on-off switches for modulated drug delivery and tissue engineering. In this study, itaconic acid (IA) was co-polymerized with N, N-diethylacrylamide (DEA) monomer to improve the LCST to the physiologic temperature about 37oC. These copolymer hydrogels were prepared by changing the initial DEA/IA molar ratio and total monomer concentration. The interior morphologies of hydrogels were characterized by scanning electron microscopy (SEM). In comparison with the PDEA hydrogel, the equilibrium swelling ratio (ESR) and LCST of the hydrogels increase with the increase of IA content in the feed. The deswelling dynamics behaviors of the different composition ratios of the P(DEA-co-IA) hydrogels on the different temperatures was investigated in detail.

Study on Superabsorbent Material in Thermal Infrared Camouflage

2014 ◽  
Vol 941-944 ◽  
pp. 370-373
Author(s):  
Nai Yan Zhang ◽  
Jiang Yu ◽  
Juan Zhang
Keyword(s):  
Chemical Structure ◽  
Monomer Concentration ◽  
Thermal Infrared ◽  
Molar Ratio ◽  
Object Temperature ◽  
Different Temperatures ◽  
Total Monomer Concentration ◽  
Equilibrium Swelling Ratio ◽  
Composition Ratios ◽  
Infrared Camouflage

Objectives, which is motional on the batter field, such as vehicles, tanks, planes, warships, firing cannons, etc. They are all active objects. On the surface of these objects there have very higher temperatures than around background, they have special pictures, and are easy found by thermal infrared reconnaissance systems. In this study, itaconic acid (IA) was co-polymerized with N, N-diethylacrylamide (DEA) monomer to improve the swelling behavior and the total absorbing water. These copolymer materials were prepared by changing the initial DEA/IA molar ratio and total monomer concentration. The chemical structure of materials was characterized by fourier transform infrared (FTIR) spectroscopy. In comparison with the PDEA hydrogel, the equilibrium swelling ratio (ESR) of the materials increase with the increase of IA content in the feed and the swelling dynamics behaviors of the different composition ratios of the P(DEA-co-IA) materials on the different temperatures was investigated in detail. Using the big hot-inertia of water, the superabsorbent material of the object surface is propitious to debase the object temperature, which suggests that these materials have potential application as thermal infrared camouflage materials.

scholarly journals Synthesis and characterization of temperature-sensitive and biodegradable hydrogel based on N-isopropylacrylamide

2010 ◽  
Vol 8 (2) ◽  
pp. 426-433 ◽  
Author(s):  
Yueqin Yu ◽  
Yanshun Li ◽  
Chunjing Zhu ◽  
Lingxiu Liu
Keyword(s):  
Enzymatic Degradation ◽  
Molar Ratio ◽  
Solution Temperature ◽  
Swelling Kinetics ◽  
Swelling Ratio ◽  
Nacl Solution ◽  
Equilibrium Swelling ◽  
Cross Linker ◽  
The Cross ◽  
Equilibrium Swelling Ratio

AbstractBased on a biodegradable cross-linker, N-maleyl chitosan (N-MACH), a series of Poly(N-isopropylacrylamide) (PNIPAAm) and Poly(N-isopropylacrylamide-co-acrylamide) [P(NIPAAm-co-Am)] hydrogels were prepared, and their lower critical solution temperature (LCST), swelling kinetics, equilibrium swelling ratio in NaCl solution, and enzymatic degradation behavior in simulated gastric fluids (SGF) were discussed. The LCST did not change with different cross-linker contents. By altering the NIPAAm/Am molar ratio of P(NIPAAm-co-Am) hydrogels, the LCST could be increased to 39°C. The LCST of the hydrogel was significantly influenced by the monomer ratio of the NIPAAm/Am but not by the cross-linker content. In the swelling kinetics, all the dry hydrogels exhibited fast swelling behavior, and the swelling ratios were influenced by the cross-linker content and NIPAAm/Am molar ratios. Equilibrium swelling ratio of all the hydrogels decreased with increasing NaCl solution concentration. In enzymatic degradation tests, the weight loss of hydrogels was dependent on the cross-linker contents and the enzyme concentration.

Effects of Polymerization Parameters on Aqueous Deposited Copolymerization of Acrylonitrile and Itaconic Acid

2013 ◽  
Vol 774-776 ◽  
pp. 508-511
Author(s):  
Ya Qi Zhao ◽  
Qiao Feng ◽  
Ling Zhi Du
Keyword(s):  
Molecular Weight ◽  
Reaction Time ◽  
High Molecular Weight ◽  
Reaction Temperature ◽  
Itaconic Acid ◽  
Temperature Region ◽  
Monomer Concentration ◽  
Initiator Concentration ◽  
Molecular Weights ◽  
Total Monomer Concentration

Pure powdery high molecular weight polyacrylonitrile (HMW-PAN) copolymers were firstly synthesized by aqueous deposited polymerization (ADP) technique employing 2,2'-Azobis (isobutyramidine) dihydrochloride (AIBA) as initiator and itaconic acid (IA) as comonomer. Various PAN polymers were obtained through changing different polymerization parameters. It is indicated that with the increase of total monomer concentration, initiator concentration, reaction temperature and reaction time, polymerization conversions of PAN copolymers all increased. While the molecular weights become greater with the increase of total monomer concentration. With the increase of initiator concentration and reaction temperature (under higher reaction temperature region), the molecular weights decreased. However, the molecular weights only had very little decrease at the end of long extension of reaction time.

scholarly journals Semi-Crystalline Copolymer Hydrogels as Smart Drug Carriers: In Vitro Thermo-Responsive Naproxen Release Study

Pharmaceutics ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 158
Author(s):  
Snežana Ilić-Stojanović ◽  
Ljubiša Nikolić ◽  
Vesna Nikolić ◽  
Slobodan Petrović ◽  
Violeta Oro ◽  
...  
Keyword(s):  
Drug Carrier ◽  
Drug Carriers ◽  
Xrd Analysis ◽  
Hplc Method ◽  
Potential Candidate ◽  
Swelling Kinetic ◽  
Model Drug ◽  
Xrd Techniques ◽  
Responsive Hydrogels

In this study, poly(N-isopropylacrylamide-co-2-hydroxypropyl methacrylate) hydrogels were synthesized using free radical initiated copolymerization method. Four hydrogels with different cross-linker concentrations were prepared. Semi-crystalline, cross-linked copolymer networks were confirmed by FTIR, SEM and XRD analysis. Variation of swelling behaviour was monitored gravimetrically and thermo-responsiveness has been noticed. An application of synthesized thermo-responsive hydrogels as carriers for the modulated release of anti-inflammatory model drug was investigated. Moreover, naproxen loading into these hydrogels was also determined using FTIR, SEM and XRD techniques and release was analyzed using HPLC method at simulated physiological conditions. Swelling kinetic and mechanism of water transport, as well as diffusion of naproxen through the hydrogels were analyzed. Thus, the aim of this work was to study various compositions of obtained hydrogels and their possibility of application as a thermo-responsive carrier for prolonged naproxen release in order to evaluate as a potential candidate for drug carrier in future pharmaceutical applications.

scholarly journals Preparation and Characterization of High-Efficiency Magnetic Heavy Metal Capture Flocculants

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1732
Author(s):  
Yuanyuan Yu ◽  
Yongjun Sun ◽  
Jun Zhou ◽  
Aowen Chen ◽  
Kinjal J. Shah
Keyword(s):  
Heavy Metal ◽  
Reaction Time ◽  
High Efficiency ◽  
Removal Rate ◽  
Low Cost ◽  
Monomer Concentration ◽  
Synthesis Process ◽  
Response Surface Optimization ◽  
Metal Capture ◽  
Total Monomer Concentration

In this study, a high-efficiency magnetic heavy metal flocculant MF@AA was prepared based on carboxymethyl chitosan and magnetic Fe3O4. It was characterized by SEM, FTIR, XPS, XRD and VSM, and the Cu(II) removal rate was used as the evaluation basis for the preparation process. The effects of AMPS content, total monomer concentration, photoinitiator concentration and reaction time on the performance of MF@AA flocculation to remove Cu(II) were studied. The characterization results show that MF@AA has been successfully prepared and exhibits good magnetic induction characteristics. The synthesis results show that under the conditions of 10% AMPS content, 35% total monomer concentration, 0.04% photoinitiator concentration, and 1.5 h reaction time, the best yield of MF@AA is 77.69%. The best removal rate is 87.65%. In addition, the response surface optimization of the synthesis process of MF@AA was performed. The optimal synthesis ratio was finally determined as iron content 6.5%, CMFS: 29.5%, AM: 53.9%, AMPS: 10.1%. High-efficiency magnetic heavy metal flocculant MF@AA shows excellent flocculation performance in removing Cu(II). This research provides guidance and ideas for the development of efficient and low-cost flocculation technology to remove Cu(II) in wastewater.

Orthogonal Test Design for Optimization of Dispersive Type Cement Slurry Fluid Loss Control Additive Used in Petroleum Drilling

2011 ◽  
Vol 361-363 ◽  
pp. 487-492
Author(s):  
Sheng Lai Guo ◽  
Yu Huan Bu
Keyword(s):  
Ph Value ◽  
Orthogonal Experiment ◽  
Monomer Concentration ◽  
Ammonium Persulfate ◽  
Fluid Loss ◽  
Oil Well ◽  
Cement Slurry ◽  
Orthogonal Test Design ◽  
Total Monomer Concentration ◽  
Loss Control

The fluid loss control additive plays a key role in reducing reservoir damage and improving the cementing quality of an oil well. Aiming at good fluid loss control ability and excellent dispersibility, a new dispersive type fluid loss control additive was synthesized through orthogonal experiment with 2-acrylamido-2- methyl propane sulfonic acid, acrylamide, N, N-dimethylacrylamide and maleic anhydride. The orthogonal experiment result shows that the influence on the properties of FLCA decreases in the order: PH value > monomer concentration > monomer mole ratio > initiator concentration > temperature. The result indicates that the optimal conditions for FLCA were 4/2.5/2.5/1 of mole ratio of AMPS/AM /NNDMA/MA, 32.5% total monomer concentration in deionized water, 1.0% (by weight of monomer) ammonium persulfate/sodium bisulfite, 4 of PH value, 40°Cof temperature. The synthesized copolymer was identified by FTIR analysis. The results show the dispersive type fluid loss control additive has excellent dispersibility, fluid loss control ability, thermal resistant and salt tolerant ability. As the temperature increases, the thickening time of the slurry containing the synthesized additive reduces. The copolymer is expected to be a good fluid loss control additive.

Influence of emulsification mode, stirring speed and volume on ibuprofen-loaded PLGA microparticles

2021 ◽  
Vol 70 (1) ◽  
pp. 32-40
Author(s):  
Holická Martina ◽  
Muselík Jan ◽  
Kubová Kateřina ◽  
Deáková Veronika ◽  
Pavloková Sylvie ◽  
...  
Keyword(s):  
Aqueous Phase ◽  
Drug Loading ◽  
Particle Morphology ◽  
Laser Diffraction ◽  
Size Reduction ◽  
Emulsion System ◽  
Solvent Evaporation Method ◽  
Particle Size Reduction ◽  
Acid Copolymer ◽  
Model Drug

Microparticles based on biodegradable synthetic lactic acid and glycolic acid copolymer (PLGA) were successfully prepared by the solvent evaporation method. Ibuprofen was chosen as the model drug. Various formulation and process parameters have been used to prepare each sample with emphasis on size reduction. The effect of the emulsification method (direct emulsification or emulsification using an ULTRA-TURRAX or a NE-1000 dispenser), the volume of the aqueous phase (200, 800 ml) and the stirring speed of the emulsion system (600, 1000 rpm) on the characteristic properties of microparticles, such as encapsulation efficiency, drug loading and particle morphology, was observed. The resulting microparticles were evaluated by optical microscopy or laser diffraction and the dissolution test was performed. It was found that the sample prepared by direct emulsification with 800 ml of an aqueous phase at 600 rpm provided the most favorable results, meanwhile the emulsification pre-step using a homogenizer caused promising particle size reduction. Gradual emulsification was evaluated as inapplicable due to great losses.

Sign in / Sign up

Export Citation Format

Share Document