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ACS Biomaterials Science & Engineering Sep 2021Bone fractures are in need of rapid fixation methods, but the current strategies are limited to metal pins and screws, which necessitate secondary surgeries upon...
Bone fractures are in need of rapid fixation methods, but the current strategies are limited to metal pins and screws, which necessitate secondary surgeries upon removal. New techniques are sought to avoid surgical revisions, while maintaining or improving the fixation speed. Herein, a method of bone fixation is proposed with transparent biopolymers anchored in place via light-activated biocomposites based on expanding CaproGlu bioadhesives. The transparent biopolymers serve as a UV light guide for the activation of CaproGlu biocomposites, which results in evolution of molecular nitrogen (from diazirine photolysis), simultaneously expanding the covalently cross-linked matrix. Osseointegration additives of hydroxyapatite or Bioglass 45S5 yield a biocomposite matrix with increased stiffness and pullout strength. The structure-property relationships of UV joules dose, pin diameter, and biocomposite additives are assessed with respect to the apparent viscosity, shear modulus, spatiotemporal pin curing, and lap-shear adhesion. Finally, a model system is proposed based on investigation with bone tissue for the exploration and optimization of UV-active transparent biopolymer fixation.
Topics: Bone Nails; Diazomethane; Durapatite; Fractures, Bone; Humans
PubMed: 34387486
DOI: 10.1021/acsbiomaterials.1c00473 -
Current Organic Synthesis 2022The dyes are synthesized by 3-Amino-2-thioxo-4thiazolidinone (N-Amino rhodanine) with glutaraldehyde or terephthalaldehyde by 2:1 mole to form a and b then coupled with...
UNLABELLED
The dyes are synthesized by 3-Amino-2-thioxo-4thiazolidinone (N-Amino rhodanine) with glutaraldehyde or terephthalaldehyde by 2:1 mole to form a and b then coupled with diazonium salts p- Amino benzenesulfonic acid and 4-Amino 3,4-disulfoazobenzeneazobenzene by 2:1 to form new different bis-mono-azo a1 and b1 and diazo a2 and b2 acid dyes. Therefore, the synthesized dyes were applied to both silk and wool fabric materials. We also evaluated the antimicrobial susceptivity of these dyed fabrics to two model gram-negative and gram-positive bacteria. Further, the chemical composition of these dyes is emphasized by an elemental analysis.
AIMS
This paper aims to synthesize and apply dye and antimicrobial to four new acid dyes based on derivatives of N-Amino rhodanine as a chromophoric group. Then, these dyes are used in dyeing silk and wool which have good lightfastness, and are also excellent for washing, rubbing and sweating fastness. Also, we measure antimicrobial susceptivity of silk and wool fabrics to Gram-negative and Gram-positive bacteria.
BACKGROUND
The new synthetic acid dyes, which have antimicrobial susceptivity to gram-negative and gram-positive bacteria, are mostly used on silk and wool fabrics which are excellent for lightfastness, washing, rubbing and sweating fastness.
OBJECTIVES
The present studies aimed at synthesis, characterization and antimicrobial susceptivity to gramnegative and gram-positive bacteria.
METHODS
The infra-red spectrum was recorded using an Infra-red spectrometer, Perkin Elmer/1650 FTIR. The 1H-NMR spectra were recorded using a Varian 400MHz spectrometer. The absorbance of the dyes was measured in the ultraviolet-visible region between 300 and 700 nm by a UNICAM UV spectrophotometer. The dye uptake by wool and silk fabrics was measured using a Shimadzu UV-2401PC (UV/V is spectrophotometer at λmax) before and after dyeing. The produced dyes were found to have a good antimicrobial susceptivity to a variety of bacteria.
RESULTS AND DISCUSSION
The compounds a1, b1, a2 &b2 show good antimicrobial activity toward gramnegative (E. coli), gram-positive (S. aurous) bacteria. The data showed that exhaustion and fastness activities of silk and wool dyed fabrics were both very high.
CONCLUSION
In this work, we prepared newly synthesized acid dyes based on 3-Amino-2-thioxo-4- thiazolidinone derivatives and used them for dyeing wool and silk fabrics. Both synthetic dyes have shown good lightfastness and fastness properties. Also, all dyes have shown a good antimicrobial effect.
Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Coloring Agents; Escherichia coli; Gram-Positive Bacteria; Silk; Thiazolidines; Wool
PubMed: 35139784
DOI: 10.2174/1570179418666210713145959 -
Journal of Colloid and Interface Science Nov 2022Electro-polymerization of diazonium salts is widely used for modifying surfaces with thin organic films. Initially this method was primarily applied to carbon, then to...
Electro-polymerization of diazonium salts is widely used for modifying surfaces with thin organic films. Initially this method was primarily applied to carbon, then to metals, and more recently to semiconducting Si. Unlike on other surfaces, electrochemical reduction of diazonium salts on Si, which is one of the most industrially dominant material, is not well understood. Here, we report the electrochemical reduction of diazonium salts on a range of silicon electrodes of different crystal orientations (111, 211, 311, 411, and 100). We show that the kinetics of surface reaction and the reduction potential is Si crystal-facet dependent and is more favorable in the hierarchical order (111) > (211) > (311) > (411) > (100), a finding that offers control over the surface chemistry of diazonium salts on Si. The dependence of the surface reaction kinetics on the crystal orientation was found to be directly related to differences in the potential of zero charge (PZC) of each crystal orientation, which in turn controls the adsorption of the diazonium cations prior to reduction. Another consequence of the effect of PZC on the adsorption of diazonium cations, is that molecules terminated by distal diazonium moieties form a compact film in less time and requires less reduction potentials compared to that formed from diazonium molecules terminated by only one diazo moiety. In addition, at higher concentrations of diazonium cations, the mechanism of electrochemical polymerization on the surface becomes PZC-controlled adsorption-dominated inner-sphere electron transfer while at lower concentrations, diffusion-based outer-sphere electron transfer dominates. These findings help understanding the electro-polymerization reaction of diazonium salts on Si en route towards an integrated molecular and Si electronics technology.
Topics: Diazonium Compounds; Electrodes; Polymerization; Salts; Surface Properties
PubMed: 35839679
DOI: 10.1016/j.jcis.2022.07.014 -
Chemistry Central Journal Nov 2017A series of recently reported phenolic azo dyes 7a-e were prepared by coupling the thienyl diazonium sulfate of 3-Amino-4H-benzo[f]thieno[3,4-c](2H)chromen-4-one with...
BACKGROUND
A series of recently reported phenolic azo dyes 7a-e were prepared by coupling the thienyl diazonium sulfate of 3-Amino-4H-benzo[f]thieno[3,4-c](2H)chromen-4-one with selected diversely substituted phenolic and naphtholic derivatives. These compounds were evaluated for their antibacterial and antifungal activities. Furthermore their voltammetric behavior was compared at a glassy carbon electrode.
RESULTS
The voltammetric behavior of the five recently reported azo dyes has been compared at a glassy carbon electrode. It is shown that the azo dyes 7a-e with a hydroxyl group in the ortho position with respect to the azo bridge give rise to well defined, irreversible peaks for the oxidation and reduction process within a pH range of 2-7. The mechanisms of electrochemical oxidation of compound 7a-c and 7e are proposed. For the hydroxyl-substituted dyes, re-oxidation peaks were obtained in the subsequent scan. The antimicrobial activities of the reported compounds 7a-e along with the entire precursors 1-4 and 6a-e were performed against selected bacterial and fungal species and their activities compared to those of nystatin, griseofulvin and ciprofloxacin used as reference drugs.
CONCLUSIONS
The present study showed significant antimicrobial activity of compounds 6d, 7a and 7c,e against the tested microorganisms; this result confirms the antimicrobial potency of azo compounds and some of their precursors.
PubMed: 29159480
DOI: 10.1186/s13065-017-0345-6 -
The Journal of Organic Chemistry Oct 2016Phenylpropargyl diazoacetates exist in equilibrium with 1-phenyl-1,2-dien-1-yl diazoacetate - allenes that are rapidly formed at room temperature through 1,3-acyloxy...
Phenylpropargyl diazoacetates exist in equilibrium with 1-phenyl-1,2-dien-1-yl diazoacetate - allenes that are rapidly formed at room temperature through 1,3-acyloxy migration catalyzed by gold(I) or gold(III) compounds, and these catalysts react solely with the π-donor rather than with the diazo group. The product allene of the aryldiazoacetates undergoes rearrangement that is not catalyzed by gold in which the terminal nitrogen of the diazo functional group adds to the central carbon of the allene, initiating a sequence of bond-forming reactions, resulting in the production of 1,5-dihydro-4H-pyrazol-4-ones in good yields. These 1,5-dihydro-4H-pyrazol-4-ones undergo intramolecular 1,3-acyl migration to form an equilibrium mixture and can quantitatively transfer the acyl group to an external nucleophile with formation of 4-hydroxypyrazoles. Reactions of phenylpropargyl phenyldiazoacetates catalyzed by cationic gold complexes are initiated at the diazo functional group to form a gold carbene whose subsequent cascade process (intramolecular addition, then aromatic substitution) results in the formation of a product that is uniquely characteristic of this pathway.
Topics: Acetates; Alkadienes; Catalysis; Diazonium Compounds; Molecular Structure; Pyrazoles; Stereoisomerism
PubMed: 27607059
DOI: 10.1021/acs.joc.6b01833 -
Advances in Colloid and Interface... Aug 2021Nanoparticles (NPs) can be prepared by simple reactions and methods from a number of materials. Their small size opens up a number of applications in different fields,... (Review)
Review
Nanoparticles (NPs) can be prepared by simple reactions and methods from a number of materials. Their small size opens up a number of applications in different fields, among which biomedicine, including: i) drug delivery, ii) biosensors, iii) bioimaging, iv) antibacterial activity. To be able to perform such tasks, NPs must be modified with a variety of functional molecules, such as drugs, targeting groups, chemical tags or antibacterial agents, and must also be prevented from aggregation. The attachment must be stable to resist during the transportation to the targeted location. Diazonium salts, which have been widely used for coupling applications and surface modification, fulfil such criteria. Moreover, they are simple to prepare and can be easily substituted with a large number of organic groups. This review describes the use of these compounds in nanomedicine with a focus on the construction of nanohybrids derived from metal, oxide and carbon-based NPs as well as viruses.
PubMed: 34237631
DOI: 10.1016/j.cis.2021.102479 -
Langmuir : the ACS Journal of Surfaces... Nov 2016We describe a simple way of modification of three silica-based fillers with in situ generated 4-hydroxymethylbenzenediazonium salt (N-CH-CHOH). The rationale for using a...
We describe a simple way of modification of three silica-based fillers with in situ generated 4-hydroxymethylbenzenediazonium salt (N-CH-CHOH). The rationale for using a hydroxyl-functionalized diazonium salt is that it provides surface-functionalized fillers that can react with phenolic resins. The modification of silica by diazonium salts was assessed using Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). FTIR spectroscopy permitted the tracking of benzene ring breathing and C-C. The absence of the characteristic N≡N stretching vibration in the 2200-2300 cm range indicates the loss of the diazonium group. XPS results indicate a higher C/Si atomic ratio after the diazonium modification of fillers and the presence of π-π* C1s satellite peaks characteristic of the surface-tethered aromatic species. Adhesion of aryl layers to the silicas is excellent because they withstand harsh thermal and organic solvent treatments. Phenolic resins (used, for example, as binders in abrasive products) were filled with diazonium-modified silicas at 10-25 wt %. The reactivity of the fillers toward phenolic resins was evaluated by the determination of the flow distance. After annealing at 180 °C, the diazonium-modified silica/phenolic resin composites were mechanically tested using the three-point flexural method. The flexural strength was found to be up to 35% higher than that of the composites prepared without any diazonium salts. Diazonium-modified silica with surface-bound -CH-OH groups is thus ideal reactive filler for phenolic resins. Such filler ensures interfacial chemical reactions with the matrix and imparts robust mechanical properties to the final composites. This specialty diazonium-modified silica will find potential application as fillers in the composites for the abrasive industry. More generally, aryl diazonium salts are a unique new series of compounds for tailoring the surface properties of fillers and tuning the physicochemical and mechanical properties of polymer composites.
PubMed: 27726385
DOI: 10.1021/acs.langmuir.6b02891 -
The subacute toxicity and underlying mechanisms of biomimetic mesoporous polydopamine nanoparticles.Particle and Fibre Toxicology Oct 2023Recently, mesoporous nanomaterials with widespread applications have attracted great interest in the field of drug delivery due to their unique structure and good...
Recently, mesoporous nanomaterials with widespread applications have attracted great interest in the field of drug delivery due to their unique structure and good physiochemical properties. As a biomimetic nanomaterial, mesoporous polydopamine (MPDA) possesses both a superior nature and good compatibility, endowing it with good clinical transformation prospects compared with other inorganic mesoporous nanocarriers. However, the subacute toxicity and underlying mechanisms of biomimetic mesoporous polydopamine nanoparticles remain uncertain. Herein, we prepared MPDAs by a soft template method and evaluated their primary physiochemical properties and metabolite toxicity, as well as potential mechanisms. The results demonstrated that MPDA injection at low (3.61 mg/kg) and medium doses (10.87 mg/kg) did not significantly change the body weight, organ index or routine blood parameters. In contrast, high-dose MPDA injection (78.57 mg/kg) is associated with disturbances in the gut microbiota, activation of inflammatory pathways through the abnormal metabolism of bile acids and unsaturated fatty acids, and potential oxidative stress injury. In sum, the MPDA dose applied should be controlled during the treatment. This study first provides a systematic evaluation of metabolite toxicity and related mechanisms for MPDA-based nanoparticles, filling the gap between their research and clinical transformation as a drug delivery nanoplatform.
Topics: Biomimetics; Nanoparticles; Diazonium Compounds
PubMed: 37807046
DOI: 10.1186/s12989-023-00548-4 -
Angewandte Chemie (International Ed. in... Jan 2020Diazomethane is one of the most versatile reagents in organic synthesis, but its utility is limited by its hazardous nature. Although alternative methods exist to...
Diazomethane is one of the most versatile reagents in organic synthesis, but its utility is limited by its hazardous nature. Although alternative methods exist to perform the unique chemistry of diazomethane, these suffer from diminished reactivity and/or correspondingly harsher conditions. Herein, we describe the repurposing of imidazotetrazines (such as temozolomide, TMZ, the standard of care for glioblastoma) for use as synthetic precursors of alkyl diazonium reagents. TMZ was employed to conduct esterifications and metal-catalyzed cyclopropanations, and results show that methyl ester formation from a wide variety of substrates is especially efficient and operationally simple. TMZ is a commercially available solid that is non-explosive and non-toxic, and should find broad utility as a replacement for diazomethane.
Topics: Antineoplastic Agents; Cyclopropanes; Diazomethane; Esterification; Humans; Models, Molecular; Nitrogen Mustard Compounds
PubMed: 31793158
DOI: 10.1002/anie.201911896 -
Archiv Der Pharmazie Jan 2021A novel series of sulfonamides, 4-(3-phenyltriaz-1-en-1-yl)-N-(4-methyl-2-pyrimidinyl)benzenesulfonamides (1-9), was designed and synthesized by the diazo reaction...
A novel series of sulfonamides, 4-(3-phenyltriaz-1-en-1-yl)-N-(4-methyl-2-pyrimidinyl)benzenesulfonamides (1-9), was designed and synthesized by the diazo reaction between sulfamerazine and substituted aromatic amines for the first time. Their chemical structures were characterized by H nuclear magnetic resonance (NMR), C NMR, and high-resolution mass spectra. The newly synthesized compounds were evaluated in terms of acetylcholineasterase (AChE) and human carbonic anhydrases (hCA) I and II isoenzymes inhibitory activities. According to the AChE inhibition results, the K values of the compounds 1-9 were in the range of 19.9 ± 1.5 to 96.5 ± 20.7 nM against AChE. Tacrine was used as the reference drug and its K value was 49.2 ± 2.7 nM against AChE. The K values of the compounds 1-9 were in the range of 10.2 ± 2.6 to 101.4 ± 27.8 nM against hCA I, whereas they were 18.3 ± 4.4 to 48.1 ± 4.5 nM against hCA II. Acetazolamide was used as a reference drug and its K values were 72.2 ± 5.4 and 52.2 ± 5.7 nM against hCA I and hCA II, respectively. The most active compounds, 1 (nonsubstituted) against AChE, 5 (4-ethoxy-substituted) against hCA I, and 8 (4-bromo-substituted) against hCA II, were chosen and docked at the binding sites of these enzymes to explain the inhibitory activities of the series. The newly synthesized compounds presented satisfactory pharmacokinetic properties via the estimation of ADME properties.
Topics: Acetylcholinesterase; Carbonic Anhydrase I; Carbonic Anhydrase II; Carbonic Anhydrase Inhibitors; Cholinesterase Inhibitors; Computer Simulation; Humans; Structure-Activity Relationship; Sulfamerazine; Triazenes
PubMed: 32984993
DOI: 10.1002/ardp.202000243