| 1. |
- Alizadeh, R., et al.
(författare)
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Synthesis of Depo-Medrol-chitosan hydrogel as new drug slow-release appliance and investigation of release kinetics by high-performance liquid chromatography
- 2016
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Ingår i: Biomedical Chromatography. - : Wiley. - 1099-0801 .- 0269-3879. ; 30:9, s. 1346-1353
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Tidskriftsartikel (refereegranskat)abstract
- The present study deals with preparation and optimization of a novel chitosan hydrogel-based matrix by suspension cross-linking method for controlled release of Depo-Medrol. The controlled release of Depo-Medrol for effective Rheumatoid arthritis disease has become an imperative field in the drug delivery system. In this context, it was intended to optimize loading circumstances by experimental design and also study the release kinetics of Depo-Medrol entrapped in the chitosan matrix in order to obtain maximal efficiency for drug loading. The optimum concentrations of chitosan (2.5g), glutaraldehyde (3.05L) and Depo-Medrol (0.1mg) were set up to achieve the highest value of drug loaded and the most sustained release from the chitosan matrix. In vitro monitoring of drug release kinetic using high-performance liquid chromatography showed that 73% of the Depo-Medrol was released within 120min, whereas remained drug was released during the next 67h. High correlation between first-order and Higuchi's kinetic models indicates a controlled diffusion of Depo-Medrol through the surrounding media. Moreover, recovery capacity >82% and entrapment efficiency of 58-88% were achieved under optimal conditions. Therefore, the new synthesized Depo Medrol-chitosan is an applicable appliance for therapy by slow release mechanism.
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| 2. |
- Barghi, Hamidreza, 1970, et al.
(författare)
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BULK HYDROPHILIC FUNTIONALIZATION OF POLYAMIDE 46
- 2013
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Patent (övrigt vetenskapligt/konstnärligt)abstract
- A modified polymer as result of a bulk functionalization of polyamide 46 (PA 46) is presented, as well as methods for synthesizing the modified polymer. This functionalization of PA 46 is performed to provide a homogenous semi-permeable polyamide 46 capable of different charges and different porosities with particles of nanoscale size in order to replace or improve other polyamide fibers used in the textile industry, filtering processes, selective sorption, controlled release devices, phase transfer catalysts, chromatography media, biocompatible capsules, artificial skins, organs, bone void repair as well as in cell bioreactors and incubators, dental impliments, medical devices, clothing, detectors, perfusion devices, in regenerative medicine, and fuel cells.
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| 3. |
- Barghi, Hamidreza, 1970, et al.
(författare)
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Catalytic Synthesis of Bulk Hydrophilic Acetaldehyde-Modified Polyamide 46
- 2014
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Ingår i: Current Organic Synthesis. - : Bentham Science Publishers Ltd.. - 1570-1794 .- 1875-6271. ; 11:2, s. 288-294
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Tidskriftsartikel (refereegranskat)abstract
- Hydrophilization of Polyamide 46 (PA46) via modification with acetaldehyde in continuous phase was studied. The chemical modification of PA 46 with acetaldehyde resulted in a water-swollen polymer with hydrophilic property. The polyamide 46 undergoes a nucleophilic addition with acetaldehyde in the presence of aluminum chloride as a catalyst. The extent of bulk hydroxyethylation using AlCl3 resulted in 95.65% modification counted as total N-hydroxyethylated polyamide 46. The modification resulted in improved hydrophilic properties, and a maximum surface free energy of 44.6 mJ/m2 was achieved after 3 h reaction, whereas the unmodified PA46 had a surface free energy of 11.2 mJ/m2. In addition, thermal properties of the polymers were studied using differential scanning calorimetry and thermogravimetric analyses. The functionalization leads to decrease in the crystallization energy from 88 J/g to 51 J/g, while the melting energy is changed from 110 J/g to 53 J/g. Furthermore, the thermal stability of the PA46 to pyrolysis was diminished after hydroxylation.
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| 4. |
- Barghi, Hamidreza, 1970, et al.
(författare)
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Synthesis of an electroconductive membrane using poly(hydroxymethyl-3,4-ethylenedioxythiophene-co-tetramethylene-N-hydrox yethyl adipamide)
- 2013
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Ingår i: Journal of Materials Chemistry C. - : Royal Society of Chemistry (RSC). - 2050-7534 .- 2050-7526. ; 1:39, s. 6347-6354
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Tidskriftsartikel (refereegranskat)abstract
- Synthesis of a novel electroconductive membrane (ECM) was studied with the aim of producing an electroconductive membrane (ECM) with low electrical resistance and appropriate mechanical properties. The method was based on copolymerization of a highly electroconductive monomer (hydroxymethyl-3,4-ethylenedioxythiophene) with highly mechanical resistant hydrophilized polyamide 46 (polytetramethylene-N-hydroxyethyl adipamide). Due to the lack of hydroxyl groups, polyamide 46 does not have the tendency to take part in any chemical reactions, therefore prior to copolymerization, PA 46 was hydrophilized with acetaldehyde to create reactive sites, which allowed copolymerization to occur. At the final stage, a very thin layer, 566 nm conductive poly(hydroxymethyl-3,4-ethylenedioxythiophene) homopolymer was localised using in situ plasma polymerization in order to improve the electrical conductivity of the obtained copolymer. The result was an adherent, highly conductive, semi-hydrophilic and flexible ECM. The presence of hydroxyl groups in the final product led to improved hydrophilicity of the conductive membrane with a surface tension of 41 mJ m(-2). The electrical resistance of PA 46 was dramatically reduced after copolymerization, to 202 in dry and 54 k Omega cm(-2) in wet conditions; furthermore, after plasma treatment, this reduction continued to 105 in dry and 2 k Omega cm(-2) in wet conditions. Other parameters such as flux flow, roughness, pore size, pore distribution, contact angle, surface energy and thermal stability of the ECM were also investigated.
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