Novel Enzymatically Synthesized Substituted Polyaniline with High Conjugation and Conductivity

MRS Advances ◽  
2018 ◽  
Vol 3 (27) ◽  
pp. 1519-1524
Author(s):  
Ferdinando F. Bruno ◽  
Ramaswamy Nagarajan ◽  
Weeradech Kiratitanavit ◽  
Nicole Favreau-Farhadi ◽  
Bora Yoon ◽  
...  
Keyword(s):  
Thin Film ◽  
Molecular Weight ◽  
Water Soluble ◽  
Enzymatic Polymerization ◽  
Polymer Complex ◽  
Unique Combination ◽  
Modeling Studies ◽  
Acidic Conditions ◽  
Enzymatic Route ◽  
Film Conductivity

ABSTRACTAn efficient enzymatic route for the synthesis of conducting oligomer of substituted aniline complexed with poly(sodium 4-styrenesulfonate) is presented. This polyelectrolyte assisted horseradish peroxidase catalyzed oligomerization of ortho-toluidine provides a route to synthesize water-soluble, highly conductive oligomers under acidic conditions. The UV-Vis, FTIR, thin film conductivity, molecular weight assessment and modeling studies of the oligomer/polymer complex indicate the presence of a thermally stable and electroactive oligomer with extended conjugation that was not present in similar conductive polymers (e.g. PANI). Moreover, the use of water-soluble templates provide a unique combination of properties such as high conductivity and processability. The same procedure was also implemented for the polymerization of 2,6-xylidine: however, the reaction did not occur suggesting a much more complex stereo-specificity of the enzymatic polymerization. Modeling studies were used to explain this behavior. The conductive poly(ortho-toluidine) can be used in chemiresistive sensors for the detection of humidity.

scholarly journals Water soluble metal-polymeric complexes of gallium and triple co-polymer of N-vinylpyrrolidone with N-vinylformamide and N-vinylminodiacetic acid

2019 ◽  
Vol 485 (3) ◽  
pp. 306-310
Author(s):  
N. I. Gorshkov ◽  
A. Yu. Murko ◽  
I. I. Gavrilova ◽  
I. I. Malakhova ◽  
V. D. Krasikov ◽  
...  
Keyword(s):  
Molecular Weight ◽  
1H Nmr ◽  
Metal Ion ◽  
Water Soluble ◽  
Polymer Complex ◽  
Nmr Data ◽  
Exclusion Chromatography ◽  
Polymeric Complexes ◽  
Metal Polymer

A terpolymer with a molecular weight of 45 kDa containing 7 mol.% of vinylamine units, 80 mol.% of vinylpyrrolidone, and 3 mol.% of vinyliminodiacetic acid units has been synthesized. Its complexation with Ga3+ ion has been studied by HPLC. The resulting metal–polymer complex has been characterized by exclusion chromatography and spectral (IR, 1H NMR) data. The complex has a monomolecular structure where the metal ion acts as an anchor fragment between vinyliminodiacetic acid units and is stable in the reaction of interligand exchange with histidine.

Conjugated polymers for thin film coating process

2001 ◽  
Vol 708 ◽  
Author(s):  
Zhexiong Tang ◽  
Wenguang Li ◽  
Cheryl Nowak ◽  
Sze Yang
Keyword(s):  
Thin Film ◽  
Molecular Weight ◽  
Acrylic Acid ◽  
Conjugated Polymers ◽  
Film Coating ◽  
Polymer Complex ◽  
Coating Process ◽  
Thin Film Coating ◽  
Polymer Complexes ◽  
Poly Acrylic Acid

ABSTRACTIn this paper, we present the syntheses of the conjugated polymers of different “effective molecular weights.” The goal is to be able to optimize the thin film coating process without compromising the electronic, optical and electroactive properties.Our strategy for controlling the effective molecular weight is to synthesize a double-strand conducting polymer that is an inter-polymer complex of a polymeric dopant and a conjugated polymer. The first strand of the two-strand complex is either a polyaniline or a polypyrrole chain, while the second strand is a poly(acrylic acid). The molecular weight of poly(acrylic acid) is used as a parameter for adjusting the coating and film-forming properties.We found that the inter-polymer complexes are dispersible in water. The dispersion stability is strongly dependent on the molecular weight of the poly(acrylic acid) strand. The dispersion is more stable for polymers synthesized with higher molecular weight of poly(acrylic acid). We also found that the particle size and particle morphology are dependent on the effective molecular weight.

Microstructural and fractographic characterization of B4C-Al cermets tested under dynamic and static loading

1989 ◽  
Vol 47 ◽  
pp. 562-563
Author(s):  
Gyeung Ho Kim ◽  
Mehmet Sarikaya ◽  
D. L. Milius ◽  
I. A. Aksay
Keyword(s):  
Thin Film ◽  
Mechanical Properties ◽  
Fracture Toughness ◽  
Static Loading ◽  
Carbon Deposition ◽  
Full Density ◽  
Unique Combination ◽  
Strong Component ◽  
Reaction Products

Cermets are designed to optimize the mechanical properties of ceramics (hard and strong component) and metals (ductile and tough component) into one system. However, the processing of such systems is a problem in obtaining fully dense composite without deleterious reaction products. In the lightweight (2.65 g/cc) B4C-Al cermet, many of the processing problems have been circumvented. It is now possible to process fully dense B4C-Al cermet with tailored microstructures and achieve unique combination of mechanical properties (fracture strength of over 600 MPa and fracture toughness of 12 MPa-m1/2). In this paper, microstructure and fractography of B4C-Al cermets, tested under dynamic and static loading conditions, are described.The cermet is prepared by infiltration of Al at 1150°C into partially sintered B4C compact under vacuum to full density. Fracture surface replicas were prepared by using cellulose acetate and thin-film carbon deposition. Samples were observed with a Philips 3000 at 100 kV.

ANALISA KANDUNGAN BETA-GLUKAN LARUT AIR DAN LARUT ALKALI DARI TUBUH BUAH JAMUR TIRAM (Pleurotus ostreatus) DAN SHIITAKE (Lentinus edodes)

2013 ◽  
Vol 13 (3) ◽  
Author(s):  
Netty Widyastuti ◽  
Teguh Baruji ◽  
Henky Isnawan ◽  
Priyo Wahyudi ◽  
Donowati Donowati
Keyword(s):  
Molecular Structure ◽  
Molecular Weight ◽  
Immune System ◽  
Pleurotus Ostreatus ◽  
Water Soluble ◽  
Low Molecular Weight ◽  
Lentinus Edodes ◽  
Beta Glucan ◽  
Oyster Mushrooms ◽  
The Difference

Beta glucan is a polysaccharide compound, generally not soluble inwater and resistant to acid. Beta glucan is used as an immunomodulator (enhancing the immune system) in mammals is usually a beta-glucan soluble in water, easily absorbed and has a low molecular weight. Several example of beta-glucan such as cellulose (β-1 ,4-glucan), lentinan (β-1 0.6-glucan) and (β-1 ,3-glucan), pleuran (β-1, 6 and β-1 ,3-glucan) are isolated from species of fungi Basidiomycota include mushrooms (Pleurotus ostreatus) and shiitake (Lentinus edodes).The purpose of thisresearch activity is to obtain beta-glucan compound that can be dissolved in water and in alkali derived from fungi Basidiomycota, i.e, Oyster mushrooms (Pleurotus ostreatus) and shiitake (Lentinus edodes). The result of beta-glucan compared to characterize the resulting beta glucan that is molecular structure . The difference of beta glucan extraction is based on the differences in solubility of beta-glucan. Beta glucan could be water soluble and insoluble water.

scholarly journals Nanoformulation and Evaluation of Oral Berberine-Loaded Liposomes

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2591
Author(s):  
Thuan Thi Duong ◽  
Antti Isomäki ◽  
Urve Paaver ◽  
Ivo Laidmäe ◽  
Arvo Tõnisoo ◽  
...  
Keyword(s):  
Thin Film ◽  
Drug Release ◽  
Size Distribution ◽  
Water Soluble ◽  
Release Behavior ◽  
Uniform Size ◽  
Ethanol Injection ◽  
Drug Release Behavior ◽  
Poorly Water Soluble

Berberine (BBR) is a poorly water-soluble quaternary isoquinoline alkaloid of plant origin with potential uses in the drug therapy of hypercholesterolemia. To tackle the limitations associated with the oral therapeutic use of BBR (such as a first-pass metabolism and poor absorption), BBR-loaded liposomes were fabricated by ethanol-injection and thin-film hydration methods. The size and size distribution, polydispersity index (PDI), solid-state properties, entrapment efficiency (EE) and in vitro drug release of liposomes were investigated. The BBR-loaded liposomes prepared by ethanol-injection and thin-film hydration methods presented an average liposome size ranging from 50 nm to 244 nm and from 111 nm to 449 nm, respectively. The PDI values for the liposomes were less than 0.3, suggesting a narrow size distribution. The EE of liposomes ranged from 56% to 92%. Poorly water-soluble BBR was found to accumulate in the bi-layered phospholipid membrane of the liposomes prepared by the thin-film hydration method. The BBR-loaded liposomes generated by both nanofabrication methods presented extended drug release behavior in vitro. In conclusion, both ethanol-injection and thin-film hydration nanofabrication methods are feasible for generating BBR-loaded oral liposomes with a uniform size, high EE and modified drug release behavior in vitro.

scholarly journals Wound Healing Promotion by Hyaluronic Acid: Effect of Molecular Weight on Gene Expression and In Vivo Wound Closure

2021 ◽  
Vol 14 (4) ◽  
pp. 301
Author(s):  
Yayoi Kawano ◽  
Viorica Patrulea ◽  
Emmanuelle Sublet ◽  
Gerrit Borchard ◽  
Takuya Iyoda ◽  
...  
Keyword(s):  
Gene Expression ◽  
Molecular Weight ◽  
Wound Healing ◽  
Hyaluronic Acid ◽  
Healing Process ◽  
Dermal Fibroblasts ◽  
Water Soluble ◽  
Wound Healing Process ◽  
And Migration ◽  
Proliferation And Migration

Hyaluronic acid (HA) has been known to play an important role in wound healing process. However, the effect of molecular weight (MW) of exogenously administered HA on the wound healing process has not been fully understood. In this study, we investigated HA with different MWs on wound healing process using human epidermal keratinocytes and dermal fibroblasts. Cell proliferation and migration ability were assessed by water soluble tetrazolium (WST) assay and wound scratch assay. We examined the effect of HA addition in a full-thickness wound model in mice and the gene expression related to wound healing. Proliferation and migration of HaCaT cells increased with the increase of MW and concentration of HA. Interleukin (IL-1β), IL-8 and vascular endothelial growth factor (VEGF) as well as matrix metalloproteinase (MMP)-9 and MMP-13 were significantly upregulated by high molecular weight (HMW) HA in keratinocytes. Together with VEGF upregulation and the observed promotion of HaCaT migration, HA with the MW of 2290 kDa may hold potential to improve re-epithelialization, a critical obstacle to heal chronic wounds.

Water soluble biguanide salts and their 1,3,5-triazine derivatives as inhibitors of acetylcholinesterase and α-glucosidase

2020 ◽  
Vol 235 (10) ◽  
pp. 465-475
Author(s):  
Ozge Gungor ◽  
Seda Nur Kertmen Kurtar ◽  
Muhammet Kose
Keyword(s):  
Spectroscopic Method ◽  
Substitute Aniline ◽  
Water Soluble ◽  
X Ray Diffraction ◽  
Nucleophilic Reaction ◽  
X Ray ◽  
Triazine Derivatives ◽  
Acidic Conditions ◽  
Approved Drugs ◽  
Solid State Structures

AbstractSeven biguanide derivatives were prepared by the nucleophilic reaction between dicyandiamide and p-substitute aniline derivatives or memantine or adamantine under acidic conditions. The cyclization of the biguanide compounds were also conducted via acetone to give 1,3,5-triazine derivatives. The structures of the synthesized compounds were characterized by analytical methods. The solid state structures of [HL5]Cl, [H2L7]Cl2, [HL1a]Cl and [HL5a]Cl were investigated by X-ray diffraction study. The acetylcholinesterase and α-glucosidase inhibitor properties of the compounds were then evaluated by the spectroscopic method. The compounds were found to show considerable acetylcholinesterase and α-glucosidase inhibitory activities compared to the approved drugs. The cyclization of biguanide derivatives with acetone did not affect inhibition of acetylcholinesterase, yet increased the α-glucosidase inhibition.

The effect of methyl and methoxy substituents on dianilines for a thermosetting polyimide system

2020 ◽  
Vol 32 (7) ◽  
pp. 801-822 ◽  
Author(s):  
John J La Scala ◽  
Greg Yandek ◽  
Jason Lamb ◽  
Craig M Paquette ◽  
William S Eck ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Molecular Weight ◽  
Glass Transition ◽  
Elevated Temperature ◽  
Methyl Substituent ◽  
Glass Transition Temperatures ◽  
High Performing ◽  
Methoxy Substituent ◽  
Acidic Conditions ◽  
Thermal Stability Of

4,4′-Methylenedianiline (MDA) is widely used in high-temperature polyimide resins, including polymerization of monomer reactants-15. The toxicity of MDA significantly limits the manufacturability using this resin. Modifying the substitution and electronics of MDA could allow for the reduction of toxicity while maintaining the high-performing properties of the materials derived from the modified MDA. The addition of a single methyl substituent, methoxy substituent, location of these substituents, and location of the amine relative to the phenolic bridge were modified as were other non-aniline diamines. Various anilines were condensed with paraformaldehyde under acidic conditions to yield dianilines. These dianilines and diamines were reacted with nadic anhydride and 3,3′,4,4′-benzophenonetetracarboxylic dianhydride in methanol to form the polyamic acid oligomers and heated at elevated temperature to form polyimide oligomers. It was found that the molecular weight of the oligomers derived from MDA alternatives was generally lower than that of MDA oligomers resulting in lower glass transition temperatures ( T gs) and degradation temperatures. Additionally, methoxy substituents further reduce the T g of the polymers versus methyl substituents and reduce the thermal stability of the resin. Methyl-substituted alternatives produced polyimides with similar T gs and degradation temperatures. The toxicity of the MDA alternatives was examined. Although a few were identified with reduced toxicities, the alternatives with properties similar to that of MDA also had high toxicities.

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