Enzymatic Template Synthesis of Polyphenol

1999 ◽  
Vol 600 ◽  
Author(s):  
Ferdinando F. Bruno ◽  
Ramaswamy Nagarajan ◽  
Jena S. Sidhartha ◽  
Ke Yang ◽  
Jayant Kumar ◽  
...  
Keyword(s):  
Water Solubility ◽  
Sol Gel ◽  
Water Soluble ◽  
Third Order ◽  
High Molecular Weight Complex ◽  
New Class ◽  
Vis Spectroscopy ◽  
Electrical Conductivities ◽  
One Step ◽  
High Degree

AbstractAn alternative, biocatalytic approach for the synthesis of a new class of water soluble and processable polyphenols is presented. In this approach, the enzyme horseradish peroxidase (HRP) is used to polymerize phenol in the presence of an ionic template. The template serves as a surfactant that can both emulsify the phenol monomer and growing polyphenol chains and provide water solubility of the final polyphenol/template complex. This approach is a simple, one step synthesis where the reaction conditions are remarkably mild and environmentally compatible. The final product is a water soluble, high molecular weight complex of polyphenol and the template used. The approach is also very versatile as numerous templates may be used to build in specific functionalities to the final polyphenol complex. Polystyrene sulfonates (SPS), lignin sulfonate and dodecyl benzene sulfonates (micelles) are the templates investigated in this study. Thermal analysis and UV-Vis spectroscopy shows that these complexes have exceptional thermal stability and a high degree of backbone conjugation. Electrical conductivities on the order of 10−5 S/cm and third order nonlinear optical susceptibilities (χ(3)) of 10−12 esu are also observed. In the case of the SPS template, under certain conditions, a sol gel complex may be formed. This enzymatic approach offers interesting opportunities in the synthesis and functionalization of a new class of processable polyphenolic materials.

scholarly journals Influence of Hybrid Sol-Gel Crosslinker on Self-Healing Properties for Multifunctional Coatings

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5382
Author(s):  
Guillaume Lollivier ◽  
Marie Gressier ◽  
Florence Ansart ◽  
Maëlenn Aufray ◽  
Marie-Joëlle Menu
Keyword(s):  
Sol Gel ◽  
Interface Layer ◽  
Hybrid Coatings ◽  
Organic Polymer ◽  
Self Healing ◽  
Oxide Interface ◽  
Protective Oxide ◽  
New Class ◽  
One Step

Self-healing polymers are a new class of material that has recently received a lot of attention because of the lifespan improvement it could bring to multiple applications. One of the major challenges is to obtain multifunctional materials which can self-heal and exhibit other interesting properties such as protection against corrosion. In this paper, the effect of the incorporation of an aminosilane on the properties of a self-healing organic polymer containing disulfide bond is studied on films and coatings for aluminium AA2024-T3 using simple one step in situ synthesis. Hybrid coatings with enhanced anticorrosion properties measured by EIS were obtained thanks to the formation of a protective oxide interface layer, while exhibiting wound closure after exposition at 75 °C. The thermal, mechanical and rheological properties of the films with different aminosilane amounts were characterized in order to understand the influence of the slight presence of the inorganic network. Stiffer and reprocessable hybrid films were obtained, capable to recover their mechanical properties after healing. The nanocomposite structure, confirmed by TEM, had a positive effect on the self-healing and stress relaxation properties. These results highlight the potential of sol-gel chemistry to obtain efficient anticorrosion and self-healing coatings.

Increasing Solubility of Poorly Water Soluble Drug Resveratrol by Surfactants and Cyclodextrins

2011 ◽  
Vol 418-420 ◽  
pp. 2231-2234 ◽  
Author(s):  
Mont Kumpugdee-Vollrath ◽  
Yvonne Ibold
Keyword(s):  
Solid Dispersion ◽  
Water Solubility ◽  
Solid Dispersions ◽  
Water Soluble ◽  
Dispersion Phase ◽  
Water Soluble Drug ◽  
Vis Spectroscopy ◽  
Anti Cancer ◽  
Cancer Agent ◽  
Span 60

Resveratrol (Res) is a polyphenolic secondary natural substance and can be used as anti-inflammatory, anti-aging, anti-heart disease and anti-cancer agent. However, Res has low water solubility which causes a low bioavailability in human body. In order to increase solubility we have prepared different inclusion complexes with native ((α, β, γ) and modified (2-hydroxypropyl-beta, dimethyl-beta) cyclodextrins (Cd) as well as solid dispersions using several surfactants (Imwitor 742, Imwitor 928, PEG 6000, Span 40, Span 60, Solutol HS15) with Res. The solubility of all mixtures was determined by UV-VIS spectroscopy at the wavelength of 305 nm. Regarding the Cd, the complex of Res with 2-hydroxypropyl-beta-Cd at a ratio of 1:3 showed the highest water solubility (248210 g/l). Concerning the surfactants, the solid dispersion from Res and Solutol HS15 showed the highest water solubility (16140 g/l). The complexation and the solid dispersion phase were confirmed by DSC. The results will be a basis for better formulation of resveratrol with higher bioavailability.

scholarly journals IMMOBILIZATION OF COBALT DISULFOPHTHALOCYANINATE ONTO POLYMETHYLOLACRYLAMIDE

2018 ◽  
Vol 61 (8) ◽  
pp. 73
Author(s):  
Galina V. Osipova ◽  
Nadezhda L. Pechnikova ◽  
Tatiana A. Ageeva
Keyword(s):  
Metal Complex ◽  
Water Solubility ◽  
Electronic Absorption Spectra ◽  
Aqueous Media ◽  
Three Dimensional ◽  
Chemical Properties ◽  
Water Soluble ◽  
Water Soluble Polymer ◽  
One Step ◽  
Insoluble Compounds

Different character of usage the porphyrins and their analogs immobilized on carrier polymers stimulates an increased interest in the synthesis and research of physico-chemical properties of porphyrin-polymer immobilizates. In this paper the peculiarities of a synthesis of water-soluble polymer systems containing cobalt disulfophthalocyaninate with the components of a different ratio are described. The methylolation reaction of polyacrylamide to immobilize cobalt disulfophthalocyaninate onto water-soluble carrier polymer has been carried out. It is known that heating polymethylolacrylamide or its solutions leads to the formation of three-dimensional structures with ether and methylene bridges. Therefore, initially the conditions for the preparation of polymethylolacrylamide with preservation of its water solubility were selected. It was found to obtain a water-soluble polymethylolacrylamide, it is necessary that the initial concentration of polyacrylamide in water did not exceed 2% by weight. The immobilization of phthalocyanine metal complex onto the modified polyacrylamide was carried out in two ways. The first is the interaction of the phthalocyanine metal complex with methylated polyacrylamide. The second is functionalization of polyacrylamide and the immobilization of phthalocyaninate metal complex onto the polymer in one-step. The introduction conditions of the cobalt disulfophthalocyaninate introduced influenced the formation of cross-linked structures in the synthesized samples. The introduction of macroheterocycle as a powder was found to promote the formation of insoluble compounds in aqueous media. Therefore, phthalocyanine metal complex was introduced into the system as 1% aqueous solution. The immobilization of the phthalocyanine metal complex onto a carrier polymer has been realized through the formation of hydrogen bonds between the methylol groups of polymethylolacrylamide and sulfo groups of the phthalocyanine metal complex and it was due to coordination interaction between the functional groups of the polymer and metallophthalocyanine as well. The amount of bound cobalt disulfophthalocyanine in the samples was determined by the electronic absorption spectra of the solutions of immobilized phthalocyanine metal complex onto the polymer. The mass content of immobilized cobalt disulfophthalocyaninate onto the polymer in the samples obtained by one-step is greater than in case of the samples obtained in two steps, the ratio of the initial reagents being the same.

scholarly journals Tetracycline Water Soluble Formulations with Enhanced Antimicrobial Activity

Antibiotics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 845
Author(s):  
A. Meretoudi ◽  
C. N. Banti ◽  
P. Siafarika ◽  
A. G. Kalampounias ◽  
S. K. Hadjikakou
Keyword(s):  
Antimicrobial Activity ◽  
Water Solubility ◽  
Attenuated Total Reflection ◽  
Water Soluble ◽  
Bacterial Strains ◽  
Scanning Calorimetry ◽  
Gram Positive ◽  
Gram Negative ◽  
Vis Spectroscopy

The negligible water solubility of tetracycline (TC), a well-known antibiotic of clinical use, is the major disadvantage for its oral administration. With the aim to improve the water solubility of TC, the micelles of formulae SLS@TC and CTAB@TC (SLS = sodium lauryl sulphate and CTAB = cetrimonium bromide) were synthesized. The micelles SLS@TC and CTAB@TC were characterized by melting point (m.p.), thermogravimetric differential thermal analysis (TG-DTA), differential scanning calorimetry (DTG/DSC), attenuated total reflection spectroscopy (FT-IR-ATR), ultra-violet visible (UV/vis) spectroscopy, proton nucleus magnetic resonance (1H-NMR) spectroscopy, and the ultrasonically-induced biregringence technique. The antimicrobial activity of SLS@TC and CTAB@TC was evaluated, by means of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and inhibition zone (IZ), against the Gram negative bacterial strains Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli) and the Gram positive ones of the genus of Staphylococcus epidermidis (S. epidermidis) and Staphylococcus aureus (S. aureus). Generally, both micelles show better activity than that of TC against the microbial strains tested. Thus, the MIC value of CTAB@TC is 550-fold higher than that of free TC against S. epidermidis. Despite the stronger activity of CTAB@TC than SLS@TC against both Gram negative and Gram positive microbes, SLS@TC is classified as a bactericidal agent (in that it eliminates 99.9% of the microbes), in contrast to CTAB@TC, which is bacteriostatic one (inhibits, but does not kill the organisms). The toxicity of SLS@TC and CTAB@TC was evaluated against human corneal eukaryotic cells (HCECs). Moreover, SLS@TC and CTAB@TC exhibit low in vivo toxicity against Artemia salina, even at concentrations up to threefold higher than those of their MICmax. Therefore, SLS@TC and CTAB@TC can be candidates for the development of new antibiotics.

Surface modification of quantum dots and magnetic nanoparticles with PEG-conjugated chitosan derivatives for biological applications

2013 ◽  
Vol 67 (11) ◽  
Author(s):  
Yan Lv ◽  
Kun Li ◽  
Yapeng Li
Keyword(s):  
Quantum Dots ◽  
Water Solubility ◽  
Thermo Gravimetric Analysis ◽  
Polymeric Micelle ◽  
Monomethyl Ether ◽  
Reduction Reaction ◽  
Water Soluble ◽  
Gravimetric Analysis ◽  
Chitosan Derivatives ◽  
Vis Spectroscopy

AbstractIn this paper, amphiphilic chitosan derivatives (N-octyl-N-mPEG-chitosan, mPEG = poly(ethylene glycol) monomethyl ether; OPEGC) were successfully synthesised via the Schiff base reduction reaction of chitosan and mPEG-aldehyde, or octanal, with chitosan acting as the backbone of the grafted copolymers, and mPEG-aldehyde providing the hydrophilic chain or octanal providing the hydrophobic alkyl chain. The synthesis was confirmed by characterisation employing Fourier transform infrared spectroscopy (FTIR) and 1H NMR. In the subsequent procedure, water-soluble quantum dots (QDs) and iron(II,III) oxide (IO) nanoparticles, widely used as nanoprobes in medical applications, were produced by the incorporation of QDs or IO inside the polymeric micelle core. Finally, the optical properties of QDs incorporated into OPEGC (OPEGC@QDs) were characterised by UV-VIS spectroscopy, fluorescence spectroscopy, cell viability was obtained through MTT, and the morphology of their assembly formed in water were observed by atomic force microscope (AFM) and transmission electron microscope (TEM) and the QDs content of OPEGC@QDs was calculated following thermo gravimetric analysis (TGA). In addition, the properties of IO incorporated into OPEGC (OPEGC@IO) were characterised by vibrating sample magnetometry (VSM), FT-IR, MTT, TGA, AFM, and TEM. The results indicated that the OPEGC composite nanoparticles with size narrowly distributed, good water solubility, and low cytotoxicity were prepared here, which represented a high quantum yield or good super-paramagnetism.

scholarly journals Influence of Magnetic Micelles on Assembly and Deposition of Porphyrin J-Aggregates

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 187 ◽  
Author(s):  
Maria Angela Castriciano ◽  
Mariachiara Trapani ◽  
Andrea Romeo ◽  
Nicoletta Depalo ◽  
Federica Rizzi ◽  
...  
Keyword(s):  
Water Solubility ◽  
Superparamagnetic Iron Oxide ◽  
Linear Dichroism ◽  
Water Soluble ◽  
Hydrophobic Core ◽  
Force Microscopy ◽  
Atomic Force ◽  
Acidic Conditions ◽  
J Aggregates ◽  
High Degree

Clusters of superparamagnetic iron oxide nanoparticles (SPIONs) have been incorporated into the hydrophobic core of polyethylene glycol (PEG)-modified phospholipid micelles. Two different PEG-phospholipids have been selected to guarantee water solubility and provide an external corona, bearing neutral (SPIONs@PEG-micelles) or positively charged amino groups (SPIONs@NH2-PEG-micelles). Under acidic conditions and with specific mixing protocols (porphyrin first, PF, or porphyrin last, PL), the water-soluble 5,10,15,20-tetrakis-(4-sulfonatophenyl)-porphyrin (TPPS) forms chiral J-aggregates, and in the presence of the two different types of magnetic micelles, an increase of the aggregation rates has been generally observed. In the case of the neutral SPIONs@PEG-micelles, PL protocol affords a stable nanosystem, whereas PF protocol is effective with the charged SPIONs@NH2-PEG-micelles. In both cases, chiral J-aggregates embedded into the magnetic micelles (TPPS@SPIONs@micelles) have been characterized in solution through UV/vis absorption and circular/linear dichroism. An external magnetic field allows depositing films of the TPPS@SPIONs@micelles that retain their chiroptical properties and exhibit a high degree of alignment, which is also confirmed by atomic force microscopy.

Dispersion of Multiwalled Carbon Nanotubes with Water-Soluble Polyaniline Blend Poly(Sodium 4-Styrenesulfonate)

2012 ◽  
Vol 229-231 ◽  
pp. 223-227 ◽  
Author(s):  
Ekarat Detsri ◽  
Stephan Thierry Dubas
Keyword(s):  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Water Solubility ◽  
Interfacial Polymerization ◽  
Composite Films ◽  
Water Soluble ◽  
Aniline Monomer ◽  
Multiwalled Carbon ◽  
Transmission Electron ◽  
Vis Spectroscopy

Water-soluble polyaniline blend poly(sodium 4-styrenesulfonate), (PANI.PSS) was used to disperse multiwalled carbon nanotubes (MWCNTs) by noncovalent surface modification. The anionic of PANI.PSS solution was prepared by interfacial polymerization of aniline monomer in the presence of PSS as the blending reagent to provide water solubility. The optimal conditions to prepare stable modified MWCNTs/PANI.PSS aqueous dispersions are presented. The interaction of MWCNTs and PANI.PSS have been investigated and explained according to the result of UV-Vis spectroscopy and zeta potential analysis. The MWCNTs/PANI.PSS complex solution was further confirmed more evidence by Transmission electron microscopy (TEM). Results showed that the MWCNTs dispersed with PANI.PSS are highly dispersible in water, which open up the new possibilities for the fabrication of composite films.

Electronic structure studies of conducting polymers by electron energy-loss spectroscopy

1996 ◽  
Vol 54 ◽  
pp. 160-161
Author(s):  
J. Fink
Keyword(s):  
Electronic Structure ◽  
Conducting Polymers ◽  
Conjugated Polymers ◽  
Electron Acceptors ◽  
Electron Donors ◽  
Light Emitting ◽  
One Dimensional ◽  
New Class ◽  
Electrical Conductivities ◽  
Electron Energy Loss

Conducting polymers comprises a new class of materials achieving electrical conductivities which rival those of the best metals. The parent compounds (conjugated polymers) are quasi-one-dimensional semiconductors. These polymers can be doped by electron acceptors or electron donors. The prototype of these materials is polyacetylene (PA). There are various other conjugated polymers such as polyparaphenylene, polyphenylenevinylene, polypoyrrole or polythiophene. The doped systems, i.e. the conducting polymers, have intersting potential technological applications such as replacement of conventional metals in electronic shielding and antistatic equipment, rechargable batteries, and flexible light emitting diodes.Although these systems have been investigated almost 20 years, the electronic structure of the doped metallic systems is not clear and even the reason for the gap in undoped semiconducting systems is under discussion.

Investigation of Au SAMs Photoclick Derivatization by PM-IRRAS

2019 ◽  
Author(s):  
Mark Workentin ◽  
François Lagugné-Labarthet ◽  
Sidney Legge
Keyword(s):  
Cell Adhesion ◽  
Self Assembly ◽  
Materials Science ◽  
Fibroblast Cell ◽  
Fine Tuning ◽  
Chemical System ◽  
Infrared Reflection ◽  
Assembled Monolayers ◽  
One Step ◽  
High Degree

In this work we present a clean one-step process for modifying headgroups of self-assembled monolayers (SAMs) on gold using photo-enabled click chemistry. A thiolated, cyclopropenone-caged strained alkyne precursor was first functionalized onto a flat gold substrate through self-assembly. Exposure of the cyclopropenone SAM to UV-A light initiated the efficient photochemical decarbonylation of the cyclopropenone moiety, revealing the strained alkyne capable of undergoing the interfacial strain-promoted alkyne-azide cycloaddition (SPAAC). Irradiated SAMs were derivatized with a series of model azides with varied hydrophobicity to demonstrate the generality of this chemical system for the modification and fine-tuning of the surface chemistry on gold substrates. SAMs were characterized at each step with polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS) to confirm successful functionalization and reactivity. Furthermore, to showcase the compatibility of this approach with biochemical applications, cyclopropenone SAMs were irradiated and modified with azide-bearing cell adhesion peptides to promote human fibroblast cell adhesion, then imaged by live cell fluorescence microscopy. Thus, the “photoclick” methodology reported here represents an improved, versatile, catalyst-free protocol that allows for a high degree of control over the modification of material surfaces, with applicability in materials science as well as biochemistry.<br>

Sign in / Sign up

Export Citation Format

Share Document