scholarly journals An Approach to the Use of Glycol Alkoxysilane–Polysaccharide Hybrids in the Conservation of Historical Building Stones

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 938
Author(s):  
Miguel Meléndez-Zamudio ◽  
Ileana Bravo-Flores ◽  
Eulalia Ramírez-Oliva ◽  
Antonio Guerra-Contreras ◽  
Gilberto Álvarez-Guzmán ◽  
...  
Keyword(s):  
Water Solubility ◽  
High Water ◽  
Water Soluble ◽  
Building Stones ◽  
Historical Building ◽  
Solubility In Water ◽  
Angle Measurements ◽  
Historical Monuments ◽  
Contact Angle Measurements ◽  
Stone Consolidants

Stone consolidants have been widely used to protect historical monuments. Consolidants and hydrophobic formulations based on the use of tetraethoxysilane (TEOS) and alkylalkoxysilanes as precursors have been widely applied, despite their lack of solubility in water and requirement to be applied in organic media. In the search for a “greener” alternative based on silicon that has potential use in this field, the use of tetrakis(2-hydroxyethyl)silane (THEOS) and tris(2-hydroxyethyl)methyl silane (MeTHEOS) as precursors, due their high water solubility and stability, is proposed in this paper. It is already known that THEOS and MeTHEOS possess remarkable compatibility with different natural polysaccharides. The investigated approach uses the water-soluble silanes THEOS–chitosan and MeTHEOS–chitosan as a basis for obtaining hybrid consolidants and hydrophobic formulations for the conservation of siliceous and calcareous stones. In the case of calcareous systems, their incompatibility with alkoxysilanes is known and is expected to be solved by the developed hybrid consolidant. Their application in the conservation of building stones from historical and archeological sites from Guanajuato, México was studied. The evaluation of the consolidant and hydrophobic formulation treatment was mainly conducted by determining the mechanical properties and contact angle measurements with satisfactory results in terms of the performance and compatibility with the studied stones.

scholarly journals Synthesis of morpholinium salts based on chloroacylated derivatives of dihydroquercetin

2019 ◽  
Vol 59 (7) ◽  
pp. 37-42
Author(s):  
Anton O. Pozdeev ◽  
◽  
Alexander M. Koroteev ◽  
Sofia N. Pimankina ◽  
Mikhail P. Koroteev ◽  
...  
Keyword(s):  
Water Solubility ◽  
Biological Activities ◽  
High Water ◽  
Water Soluble ◽  
Synthetic Approach ◽  
Solubility In Water ◽  
Natural Amino Acids ◽  
Synthetic Approaches ◽  
Derivatives Of ◽  
Low Solubility

The flavonoid dihydroquercetin and its esterified derivatives possess various biological activities and are widely used as dietary supplements and in pharmacology. A significant disadvantage of this flavonoid is its low solubility in water at ordinary temperatures of up to 0.03%, which negatively affects its biological activity. Nature overcomes this problem by glycosylation, sulfation, and phosphorylation. In chemistry and pharmacology to overcome this problem, there are several synthetic approaches. For dihydroquercetin (DHQ) is the inclusion of DHQ in the cyclodextrin matrix or the formation of a complex of DHQ with basic natural amino acids. In this paper, a method is proposed for obtaining water-soluble morpholinium salts based on chloroacylated derivatives of DHQ. The acylation reaction was carried out in dioxane, pyridine was used as an acceptor of choric hydrogen. The target compounds were obtained with a yield of 68-79%. As a result, chlorinated derivatives based on DHQ and its acyl and benzyl derivatives were synthesized. These derivatives in the interaction with morpholine form its salts, which, as it turned out, have a high water solubility. Pentamorpholine salt of DHQ had the highest solubility in water, up to 6.5% at room temperature, which is 200 times more soluble than the original DHQ. The proposed synthetic approach to increase the water solubility of acyl derivatives of DHQ can be extended using other nitrogenous bases and other haloacyl derivatives of DHQ.

scholarly journals New Active Pharmaceutical Ingredient-Ionic Liquids (API-ILs) Derived from Indomethacin and Mebendazole

Proceedings ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 48 ◽  
Author(s):  
◽  
Emilia Tojo
Keyword(s):  
Ionic Liquids ◽  
Water Solubility ◽  
Methanesulfonic Acid ◽  
Active Pharmaceutical Ingredient ◽  
High Water ◽  
Solubility In Water ◽  
Pharmaceutical Ingredients ◽  
Low Toxicity ◽  
Low Solubility ◽  
High Water Solubility

The transformation of two solid Active Pharmaceutical Ingredients (APIs) into new ionic liquids (IL)s that incorporate APIs (API-ILs) is reported. The structures of the APIs (indomethacin and mebendazole) were selected by their susceptibility to being transformed into API-ILs (either to form the cation or the anion) and their limited bioavailability due to their low solubility in water. The counterions, such as those derived from 2-dimethylaminoethanol (DMEA), tetramethylguanidine (TMG), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,4-diazabicyclo[2.2.2] (TED), <i>p</i>-toluensulfonic acid, glycolic acid, methanesulfonic acid, and saccharin, were carefully chosen, aiming for high biocompatibility, low toxicity, and high water solubility. The synthesis was carried out by direct treatment of the API with the corresponding selected acid or base. Finally, the solubility in water of all the synthesized salts was determined.

Exploration on the adsorption mechanism of aminopyrimidines and quinazoline compounds on graphene oxide: Hydrophobicity and structure-controlled release process

2019 ◽  
Vol 9 (5) ◽  
pp. 419-428
Author(s):  
Li Li ◽  
Chunjiao Pan ◽  
Zhongqiu Guo ◽  
Bingmi Liu ◽  
Hao Pan ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Computer Simulations ◽  
Water Solubility ◽  
High Water ◽  
Water Soluble ◽  
Release Process ◽  
Adsorption Mechanisms ◽  
Mechanical Stirring

In this study, graphene oxide was synthesized using the Hummers method, and stable and homogeneous graphene oxide aqueous solutions were obtained through mechanical stirring and ultrasonic stripping. In conjunction with our previous studies, graphene oxide-loaded insoluble compound delivery systems were prepared to verify the in vivo release profiles of the graphene oxide delivery system. Several insoluble compounds including imatinib, nilotinib, erlotinib, gefitinib, and afatinib were selected for loading and in vitro graphene oxide release assays to study the non-covalent adsorption mechanisms. Computer simulations were employed for validation processes. For in vivo release assays, the T1/2 values of the poorly water soluble groups were 1.104 ± 0.18 h and the Cmax was 2.600 ± 2.06 mg/L. In previous assays, compounds with high water solubility supported by graphene oxide were released and detected in vivo. The solubility of the compound and its binding force with the carrier played a crucial role in release. The results of graphene oxide loading experiments showed that the maximum loading and entrapment efficiencies of the insoluble model compounds with similar aromatic rings were comparable. Under basic conditions, the in vitro release rates and maximum release levels of amino pyrimidine were elevated. In contrast, quinazoline release declined. Combined with computer simulations, π–π stacking was identified as the dominant mechanism for adsorption onto graphene oxide. Both hydrogen bonding and cation-π bonds played an auxiliary reinforcing role, and the two were regarded as antagonistic.

scholarly journals Strategies to Improve the Properties of Amaranth Protein Isolate-Based Thin Films for Food Packaging Applications: Nano-Layering through Spin-Coating and Incorporation of Cellulose Nanocrystals

Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2564
Author(s):  
Amparo López-Rubio ◽  
Adriana Blanco-Padilla ◽  
Kristiina Oksman ◽  
Sandra Mendoza
Keyword(s):  
Contact Angle ◽  
Optical Properties ◽  
Cellulose Nanocrystals ◽  
Spin Coating ◽  
Food Packaging ◽  
Water Solubility ◽  
Protein Isolate ◽  
Water Soluble ◽  
Water Contact ◽  
Angle Measurements

In this work, two different strategies for the development of amaranth protein isolate (API)-based films were evaluated. In the first strategy, ultrathin films were produced through spin-coating nanolayering, and the effects of protein concentration in the spin coating solution, rotational speed, and number of layers deposited on the properties of the films were evaluated. In the second strategy, cellulose nanocrystals (CNCs) were incorporated through a casting methodology. The morphology, optical properties, and moisture affinity of the films (water contact angle, solubility, water content) were characterized. Both strategies resulted in homogeneous films with good optical properties, decreased hydrophilic character (as deduced from the contact angle measurements and solubility), and improved mechanical properties when compared with the neat API-films. However, both the processing method and film thickness influenced the final properties of the films, being the ones processed through spin coating more transparent, less hydrophilic, and less water-soluble. Incorporation of CNCs above 10% increased hydrophobicity, decreasing the water solubility of the API films and significantly enhancing material toughness.

scholarly journals Amphiphilic Polyphosphonate Copolymers as New Additives for PDMS-Based Antifouling Coatings

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3414
Author(s):  
Elisa Guazzelli ◽  
Niccolò Lusiani ◽  
Gianfranca Monni ◽  
Matteo Oliva ◽  
Chiara Pelosi ◽  
...  
Keyword(s):  
Water Soluble ◽  
Model Organisms ◽  
Water Contact ◽  
Angle Measurements ◽  
Antifouling Coatings ◽  
Contact Angle Measurements ◽  
Biological Tests ◽  
Poly Ethylene ◽  
Alternative Solutions ◽  
Hydrolysis Of

Poly(ethyl ethylene phosphonate)-based methacrylic copolymers containing polysiloxane methacrylate (SiMA) co-units are proposed as surface-active additives as alternative solutions to the more investigated polyzwitterionic and polyethylene glycol counterparts for the fabrication of novel PDMS-based coatings for marine antifouling applications. In particular, the same hydrophobic SiMA macromonomer was copolymerized with a methacrylate carrying a poly(ethyl ethylene phosphonate) (PEtEPMA), a phosphorylcholine (MPC), and a poly(ethylene glycol) (PEGMA) side chain to obtain non-water soluble copolymers with similar mole content of the different hydrophilic units. The hydrolysis of poly(ethyl ethylene phosphonate)-based polymers was also studied in conditions similar to those of the marine environment to investigate their potential as erodible films. Copolymers of the three classes were blended into a condensation cure PDMS matrix in two different loadings (10 and 20 wt%) to prepare the top-coat of three-layer films to be subjected to wettability analysis and bioassays with marine model organisms. Water contact angle measurements showed that all of the films underwent surface reconstruction upon prolonged immersion in water, becoming much more hydrophilic. Interestingly, the extent of surface modification appeared to be affected by the type of hydrophilic units, showing a tendency to increase according to the order PEGMA < MPC < PEtEPMA. Biological tests showed that Ficopomatus enigmaticus release was maximized on the most hydrophilic film containing 10 wt% of the PEtEP-based copolymer. Moreover, coatings with a 10 wt% loading of the copolymer performed better than those containing 20 wt% for the removal of both Ficopomatus and Navicula, independent from the copolymer nature.

scholarly journals Chitosan-grafted-poly(aniline-co-anthranilic acid) as a water soluble binder to form 3D structures for Si anodes

RSC Advances ◽  
2020 ◽  
Vol 10 (13) ◽  
pp. 7643-7653 ◽  
Author(s):  
Eunsoo Kim ◽  
Rajeev K. K. ◽  
Jaebin Nam ◽  
Junyoung Mun ◽  
Tae-Hyun Kim
Keyword(s):  
Anthranilic Acid ◽  
Water Solubility ◽  
High Water ◽  
Water Soluble ◽  
Polymeric Binder ◽  
3D Structures ◽  
Si Anodes ◽  
Poly Aniline ◽  
High Water Solubility

We develop a polymeric binder with outstanding cell properties, and high water solubility for Si anodes by grafting a conductive PAAA onto chitosan.

scholarly journals High-Performance Dental Adhesives Containing an Ether-Based Monomer

2019 ◽  
Vol 99 (2) ◽  
pp. 189-195 ◽  
Author(s):  
S. Yamauchi ◽  
X. Wang ◽  
H. Egusa ◽  
J. Sun
Keyword(s):  
Contact Angle ◽  
Bond Strength ◽  
Shear Bond Strength ◽  
Water Solubility ◽  
Dental Restoration ◽  
Dental Adhesives ◽  
Dental Resins ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Dentin Tubules

Dental adhesives are vital for the success of dental restorations. The objective of this study is to make strong and durable dental adhesives that are free from 2 symbolic methacrylate-based dental resins—2-bis[4-(2-hydroxy-3-methacryl-oxypropoxy)-phenyl]-propane (Bis-GMA) and 2-hydroxyethyl-methacrylate (HEMA)—and have equivalent/improved bonding strength and durability. We formulated, prepared, and evaluated 2 dental adhesives using mixtures of a hydrolytically stable ether-based monomer, triethylene glycol divinylbenzyl ether (TEG-DVBE), with urethane dimethacrylate (UDMA) or pyromellitic glycerol dimethacrylate. These adhesives were composed of equimolar ester-/ether-based vinyl functional groups. They were compared with Bis-GMA/HEMA-based commercial and experimental dental adhesives in terms of shear bond strength and microtensile bond strength (µTBS) to human dentin and the µTBS bond stability under extended thermocycling challenges. In addition, the resins’ infiltration to dentin tubules, mechanical performance, and chemical properties were assessed by scanning electron microscopy, ISO standard flexural strength and modulus measurements, contact angle measurements, and water sorption/solubility measurements. The hybrid TEG-DVBE-containing dental adhesives generated equivalent shear bond strength and µTBS in comparison with the controls. Significantly, these adhesives outperformed the controls after being challenged by 10,000 thermocycles between 5 °C and 55 °C. Water contact angle measurements suggested that the hybrid dental adhesives were relatively more hydrophobic than the Bis-GMA/HEMA controls. However, both TEG-DVBE-containing adhesives developed more and deeper resin tags in dentin tubules and formed thicker hybrid layers at the composite-dentin interface. Furthermore, the water solubility of UDMA/TEG-DVBE resins was reduced approximately 89% in comparison with the Bis-GMA/HEMA controls. The relatively hydrophobic adhesives that achieved equivalent/enhanced bonding performance suggest great potentials in developing dental restoration with extended service life. Furthermore, the TEG-DVBE-containing materials may find wider dental applications and broader utility in medical device development.

scholarly journals Radical Dendrimers Based on Biocompatible Oligoethylene Glycol Dendrimers as Contrast Agents for MRI

Pharmaceutics ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 772 ◽  
Author(s):  
Songbai Zhang ◽  
Vega Lloveras ◽  
Daniel Pulido ◽  
Flonja Liko ◽  
Luiz F. Pinto ◽  
...  
Keyword(s):  
Contrast Agents ◽  
First Generation ◽  
Water Solubility ◽  
High Water ◽  
Mri Contrast Agents ◽  
The Body ◽  
Water Soluble ◽  
Mri Contrast ◽  
Oligoethylene Glycol ◽  
Magnetic Resonance Imaging Mri

Finding alternatives to gadolinium (Gd)-based contrast agents (CA) with the same or even better paramagnetic properties is crucial to overcome their established toxicity. Herein we describe the synthesis and characterization of entirely organic metal-free paramagnetic macromolecules based on biocompatible oligoethylene glycol dendrimers fully functionalized with 5 and 20 organic radicals (OEG Gn-PROXYL (n = 0, 1) radical dendrimers) with the aim to be used as magnetic resonance imaging (MRI) contrast agents. Conferring high water solubility on such systems is often a concern, especially in large generation dendrimers. Our approach to overcome such an issue in this study is by synthesizing dendrimers with highly water-soluble branches themselves. In this work, we show that the highly water-soluble OEG Gn-PROXYL (n = 0, 1) radical dendrimers obtained showed properties that convert them in good candidates to be studied as contrast agents for MRI applications like diagnosis and follow-up of infectious diseases, among others. Importantly, with the first generation radical dendrimer, a similar r1 relaxivity value (3.4 mM−1s−1) in comparison to gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) used in clinics (3.2 mM−1s−1, r.t. 7T) has been obtained, and it has been shown to not be cytotoxic, avoiding the toxicity risks associated with the unwanted accumulation of Gd in the body.

scholarly journals Biodegradability of Polyvinyl Alcohol Based Film Used for Liquid Detergent Capsules

2021 ◽  
Vol 58 (2) ◽  
pp. 88-96
Author(s):  
Dominic Byrne ◽  
Geert Boeije ◽  
Ian Croft ◽  
Gerd Hüttmann ◽  
Gerard Luijkx ◽  
...  
Keyword(s):  
Polyvinyl Alcohol ◽  
Water Solubility ◽  
Cold Water ◽  
High Water ◽  
Water Soluble ◽  
Screening Tests ◽  
Potential Contribution ◽  
Film Material ◽  
Liquid Detergent ◽  
Washing Process

Abstract Questions and potential misperceptions have arisen about the potential contribution of liquid detergent capsules to the environmental microplastics issue. The film of these detergents is highly water soluble, also in cold water, as it must fully dissolve during every type of washing process. Water-soluble grades of polyvinyl alcohol, the most commonly used detergent capsule film material, are recognised to be biodegradable. In the current paper, adequate biodegradability is confirmed by means of ready biodegradation screening tests, across a range of polyvinyl alcohol detergent grade films. The high water solubility in itself implies that detergent capsule films are not within the microplastic scope. Furthermore, their biodegradability ensures there is no concern for persistence or accumulation in the environment.

scholarly journals The Water-Soluble Chitosan Derivative, N-Methylene Phosphonic Chitosan, Is an Effective Fungicide against the Phytopathogen Fusarium eumartii

2021 ◽  
Vol 37 (6) ◽  
pp. 533-542
Author(s):  
Florencia Anabel Mesas ◽  
María Cecilia Terrile ◽  
María Ximena Silveyra ◽  
Adriana Zuñiga ◽  
María Susana Rodriguez ◽  
...  
Keyword(s):  
Water Solubility ◽  
Water Soluble ◽  
Phytopathogenic Fungus ◽  
Oxygen Species ◽  
Chitosan Derivative ◽  
Solubility In Water ◽  
Environmental Friendly ◽  
Antifungal Effects ◽  
Species Production ◽  
Low Solubility

Chitosan has been considered an environmental-friendly polymer. However, its use in agriculture has not been extended yet due to its relatively low solubility in water. N-Methylene phosphonic chitosan (NMPC) is a water-soluble derivative prepared by adding a phosphonic group to chitosan. This study demonstrates that NMPC has a fungicidal effect on the phytopathogenic fungus Fusarium solani f. sp. eumartii (F. eumartii) judged by the inhibition of F. eumartti mycelial growth and spore germination. NMPC affected fungal membrane permeability, reactive oxygen species production, and cell death. Also, this chitosan-derivative exerted antifungal effects against two other phytopathogens, Botrytis cinerea, and Phytophthora infestans. NMPC did not affect tomato cell viability at the same doses applied to these phytopathogens to exert fungicide action. In addition to water solubility, the selective biological cytotoxicity of NMPC adds value in its application as an antimicrobial agent in agriculture.

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