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Objectives: The glow discharge plasma (GDP) procedure has proven efficacy in grafting allylamine onto zirconia dental implant surfaces to enhance osseointegration. This study explored the enhancement of zirconia dental implant properties using GDP at different energy settings (25, 50, 75, 100, and 200 W) both in vitro and in vivo. Materials and Methods: In vitro analyses included scanning electron microscopy, wettability assessment, energy‐dispersive X‐ray spectroscopy, and more. In vivo experiments involved implanting zirconia dental implants into rabbit femurs and later evaluation through impact stability test, micro‐CT, and histomorphometric measurements. Results: The results demonstrated that 25 and 50 W GDP allylamine grafting positively impacted MG‐63 cell proliferation and increased alkaline phosphatase activity. Gene expression analysis revealed upregulation of OCN, OPG, and COL‐I. Both 25 and 50 W GDP allylamine grafting significantly improved zirconia's surface properties (p <.05, p <.01, p <.001). However, only 25 W allylamine grafting with optimal energy settings promoted in vivo osseointegration and new bone formation while preventing bone level loss around the dental implant (p <.05, p <.01, p <.001). Conclusions: This study presents a promising method for enhancing Zr dental implant surface's bioactivity. [ABSTRACT FROM AUTHOR]

The reaction of allyl(furfuryl)amines with aroyl isothiocyanates was studied. The reaction proceeded via an initial nucleophilic addition of the allylamine nitrogen atom to isothiocyanates and a subsequent spontaneous intramolecular Diels–Alder reaction involving the furan ring of intermediate N-allyl-N-furfurylthioureas with the formation of a single diastereomer of 3a,6-epoxyisoindoles. [ABSTRACT FROM AUTHOR]

This article discusses the regioselective anti-addition of silyllithiums to propargylic amines. The authors explore the use of nitrogen functional groups as directing groups for silyl metal species. They investigate the reaction using variously functionalized propargylic amines and optimize the reaction conditions. The authors also demonstrate the potential for one-pot transformations from chiral N-sulfinyl imines to form silylated allylic amines. Overall, this research provides insights into the synthesis of alkenylsilanes and their potential applications in chemical transformations. [Extracted from the article]

The [Ru(p‐cymene)Cl2]2‐catalyzed reaction of 2‐arylpyridines with 1‐aryl‐2‐vinylpyrrolidines is carried out in CF3CH2OH at 40 °C in the presence of KOAc, affording ortho‐C−H allylation products of arenes in 29 % to 99 % yields and 1:0.7 to 1 : 5.4 Z/E ratio. The amino groups remain in the product molecules. The protocol suits for a wide scope of substrates and tolerates functional groups including alkyl, aryl, MeO, F, Cl, Br, OCF3, and CF3 groups. [ABSTRACT FROM AUTHOR]

Introduction: To overcome the genuine bioinert properties of zirconia ceramic, functionalization of the surface with the bioactive protein fibronectin was conducted.Methods: Glow discharge plasma (GDP)-Argon was first used to clean the zirconia surface. Then allylamine was treated at three different powers of 50 W, 75 W, and 85 W and immersed into 2 different fibronectin concentrations (5 µg/ml and 10 µg/ml).Results and Discussion: After surface treatment, irregularly folded protein-like substances were attached on the fibronectin coated disks, and a granular pattern was observed for allylamine grafted samples. Infrared spectroscopy detected C-O, N-O, N-H, C-H, and O-H functional groups for fibronectin treated samples. Surface roughness rose and hydrophilicity improved after the surface modification, with MTT assay showing the highest level of cell viability for the A50F10 group. Cell differentiation markers also showed that fibronectin grafted disks with A50F10 and A85F10 were the most active, which in turn encouraged late-stage mineralization activity on 21d. Up-regulation of osteogenic related mRNA expression from 1d to 10d can be observed in RT-qPCR data for ALP, OC, DLX5, SP7, OPG and RANK biomarkers. These physical and biological properties clearly indicate that an allylamine and fibronectin composite grafted surface significantly stimulated the bioactivity of osteoblast-like cells, and can be utilized for future dental implant applications.

The ruthenium(II)‐catalyzed reaction of aniline derivatives with allylamines was carried out, affording 2‐methylindoles via C−H/C−N bond activation. 4,5‐Dimethyl pyrimidin‐2‐yl group attached on the nitrogen atom of anilines is the most effective directing group and N‐allyl‐4‐fluoro‐N‐methylaniline is the optimal allylamine. The cyclization products were obtained in 16% to 96% yields. The method does not require external oxidant. A possible mechanism is proposed. [ABSTRACT FROM AUTHOR]

In this study, 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) and allylamine (AA) were copolymerized in an aqueous solution via free radical polymerization using ammonium persulfate as the initiator. The chemical structure and compositions of the copolymers were confirmed by elemental analysis, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR). Monomer reactivity ratios were determined by Fineman-Ross (rAMPS = 0.91 ± 0,01 and rAA = 0.40 ± 0.02), Kelen-Tudos (rAMPS = 1.10 ± 0.02 and rAA = 0.45 ± 0.01) and inverted Fineman-Ross (rAMPS = 0.85 ± 0.01 and rAA = 0.31 ± 0.03) methods. AMPS was found to be more reactive than AA and copolymers had a random composition. The flocculation performance of the copolymer was evaluated in Fe(OH)3 hydrosol. When the concentration of the copolymer in the hydrosol was more than 15 mg/L, the concentration of Fe3+ ions decreased up to 15 times due to flocculation of hydrosol particles. Effect of the concentration of AMPS-AA copolymer on the electropotential (zeta) and particle size of the hydrosol Fe(OH)3 were also studied systematically. It was determined that the zeta potential of the particles decreased from + 58 to + 20 mV and the average particle size of the hydrosol increased approximately 30 times when copolymer concentration in the hydrosol reached to 20 mg/L. [ABSTRACT FROM AUTHOR]

For the generation of tailor-made polymer coatings on nanofibrous nonwovens plasma enhanced chemical vapor (PECVD) is a promising process, even for complex geometries. The plasma coatings can greatly improve their suitability for biomedical applications by optimising biocompatibility to the local needs, especially for cardiovascular disease treatments. Therein, wound healing and endothelialisation are important steps which are connected by a complex interaction. The monomers allylamine and hexamethyldisiloxane, as well as different process conditions were studied for the coating of nanofibrous thermoplastic silicone polycarbonate polyurethane (TSPCU) nonwovens. Aim of this study was to investigate the feasibility of plasma polymer coating under preservation of the nanofibrous morphological structure. Beside characterization of the nonwoven, biological evaluation with endothelial and fibroblast cells was performed. The prepared nonwoven samples support the feasibility of plasma coating under preservation of the nanofibrous structure. Also, different effects of the surfaces in contact with fibroblasts and endothelial cells could be observed.

Polyelectrolytes show complexation by the other polymers having opposite charges. Allyamine (AlAm) is a cationic monomer, and vinyl sulfonic acid (VSA) is an anionic monomer. AlAm and its copolymer with VSA are excellent polyelectrolytes that can be used in aqueous systems. In this work, we aimed to synthesize the allylamine hydrochloride-vinyl sulfonic acid (AlAm.HCl/VSA) copolymers in different mole ratios on feed composition by the free radical polymerization method at 50 °C for 50 h with a thermal initiator 2,2'-azo-bis(2-methylpropanediamine) dihydrochloride. Furthermore, we aimed to obtain copolymer compositions by FT-IR, Raman, and NMR spectroscopy methods. Because of the overlapping obtained peaks from the mentioned methods above, we used Elemental analysis. The monomer reactivity ratios were calculated by Fineman-Ross (FR), Kelen-Tudos (KT), Mayo-Lewis (ML), and Inverted Fineman-Ross (iFR) methods. These ratios were calculated for AlAm.HCl and VSA as r1 = 0.3613 and r2 = 1.0896 via FR method; r1 = 0.3731 and r2 = 1.1169 by the KT method; r1 = 0.3574 and r2 = 1.0552 via ML method; and r1 = 0.3375, r2 = 1.0772 by the iFR method, respectively. Deacidified copolymer is obtained in (38.369:61.631) actual composition (AlAm/VSA) at 2.9 molar sodium hydroxide solution in methanol. In an evaluation of the kinetic behavior of (38.369:61.631) in actual composition, it is shown that the copolymer conversion rate is a kind of second-order reaction. For investigation of structural behavior, Raman- FT-IR–NMR (1H, 13C, DEPT135, Cosy) was used. Thermal properties were investigated by thermal gravimetry analysis (TGA). [ABSTRACT FROM AUTHOR]

The complex formation between allylamine and mineral acids (HCl, H2SO4, H3PO4) and their stabilities were investigated by Uv-Vis, DSC and TGA analyses. Free radical polymerization of allylamine salts was achieved by using 2,2′-azobis (2-methylpropanediamine)dihydrochloride at 50oC under N2 atmosphere in water. PAlAm synthesized in the presence of H2SO4 and H3PO4 were insoluble in water due to physical crosslinking of chains. They were converted to water soluble PAlAm.HCl by HCl treatment for further characterization. The structures of polymers obtained were elucidated by FT-IR, 1H NMR, 13C, and Cosy NMR spectroscopies. Thermal stability and glass transition behaviors were investigated by TGA and DSC. Tg was found to be 225°C for poly (AlAm.HCl) whereas 23°C for poly (AlAm). The poly (AlAm) showed very high heat stability with no weight loss until 440°C in nitrogen atmosphere. The molecular weight of PAlAm.HCl was determined by 1H NMR and viscosimetry to be 16,000 and 12,000 respectively. [ABSTRACT FROM AUTHOR]

The reaction of 5-arylisoxazolyl- and 4,5-dichloroisothiazolylallylamines with pyromucic acid chlorides (2-furoyl and 5-methyl-2-furoyl chlorides) was studied. The reaction proceeds via the initial acylation of the allylamine nitrogen atom and the subsequent spontaneous intramolecular Diels–Alder reaction involving the furan ring of intermediate N-furoylamides with the formation of a single diastereomer of 3a,6-epoxyisoindol-3-ones. [ABSTRACT FROM AUTHOR]

Solution‐based amine absorption technologies have been widely applied for CO2 capture, but they have several drawbacks. This paper reports on the synthesis of the first solid‐state amine adsorbent prepared through a simple plasma polymerization and deposition on physicochemically modified natural mordenite–clinoptilolite zeolite. The plasma deposition of amine polymer under certain conditions resulted in a significant increase in surface area‐weighted CO2 adsorption capacity as the natural zeolite. The strength of the interaction between CO2 and the adsorbent was weaker for the plasma polymer‐modified zeolite than without the plasma coating, which may facilitate regeneration. Both indications make the amine plasma polymer‐based zeolite adsorbent a good candidate for CO2 adsorption and separation. [ABSTRACT FROM AUTHOR]

Chemically patterned surfaces for biotechnology applications often require sub‐micron patterns to match specific sub‐cellular structures and control the presentation of proteins to single cell arrays. Plasma polymer coatings are used extensively in the biotechnology sector for biomaterials, cell culture and tissue engineering, but their patterning has not been investigated at the sub‐micron level. The resolution limit of plasma polymerized patterns with designed line widths of 900 to 20 nm is investigated via dual chemistry patterns of plasma polymerized acrylic acid and allylamine created with poly (methyl methacrylate) resist and electron beam lithography (EBL). Line widths are characterized via scanning electron microscopy and atomic force microscopy with surface chemistry analysis via time‐of‐flight secondary‐ion mass spectrometry (ToF‐SIMS). The smallest line width measured is 29 nm for a designed line width of 20 nm. High‐resolution nanoscale imaging is achieved using ToF‐SIMS, with lines down to ≈60 nm in width visible. This work demonstrates the successful fabrication and characterization of sub 100 nm dual plasma polymer patterns using EBL, establishing a clear route for large scale production of plasma polymerized nanopatterning. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: A facile synthetic method for the construction of 3‐azabicyclo[3.1.0]hexane in the presence of copper catalyst system was developed. The reaction proceeds through Michael addition of allylamines with allenes followed by copper‐mediated intramolecular oxidative carbanion 5‐exo‐trig radical cyclization, affording potential biologically active 3‐azabicyclo[3.1.0]hexane derivatives in moderate to high yields (42%—85%). [ABSTRACT FROM AUTHOR]

A number of new pyrazole and pyrimidine derivatives containing an allylmorpholine fragment were obtained by reactions of chromone-containing allylmorpholines with 1,2- and 1,3-binucleophiles (hydrazine, guanidine, acetamidine). The syntheses were carried out under mild conditions (ethanol, room temperature), and the target products were isolated with high yields. The obtained compounds are of interest as potential cholinesterase inhibitors. [ABSTRACT FROM AUTHOR]

This article studies the reactions and mechanisms of H8Si8O12 (T8H8) molecules with n‐propanol, acetone, allyl alcohol, n‐butylamine, allylamine, acetic acid, and 1‐octene in air, at room temperature, and without catalysts. The reaction between T8H8 and n‐propanol involves both the highly polarized SiO and SiH bonds and results in cage breakage and forming Q4 and Q3 structures with OC3H7 in the reaction product. T8H8 also reacts with acetone, and the resultant product possesses SiOCH(CH3)2. Allyl alcohol is less reactive to cause T8H8 decomposition, and the resultant product contains SiOCH2CHCH2 and SiOCH2(CH2)3CHCH2. However, it is found that basically T8H8 does not react with acetic acid and 1‐octene. In the reactions of T8H8 with n‐butylamine and allylamine, the resultant products contain SiNH(CH2)3CH3 and SiNHCH2CHCH2, respectively. For the reaction with T8H8, allylamine is less active than n‐butylamine. Possible mechanisms for the T8H8 reactions are discussed. [ABSTRACT FROM AUTHOR]

This study developed a promising approach (low-temperature plasma polymerization with allylamine) to modify the titanium (Ti) surface, which helps the damaged tissue to heal faster. The Ti surface was first cleaned by argon (Ar) plasma, and then the functional amino-groups were coated on the Ti surface via plasma polymerization. The topography characteristics, wettability, and optimal plasma modification parameters were investigated through atomic force spectroscopy, secondary ion mass spectroscopy, and response surface methodology (RSM). Analytical results showed that the formation of a porous surface was found on the Ar plasma-modified Ti surfaces after Ar plasma modification with different parameters. The Ar plasma modification is an effective approach to remove surface contaminants and generate a porous topography on the Ti surface. As the Ti with Ar plasma modification was at 100 W and 190 m Torr for 12 min, the surface exhibited the maximum hydrophilic performance. In the allylamine plasma modifications, the contact angle values of the allylamine plasma-modified Ti surfaces varied between 70.15° and 88.26° in the designed parameters. The maximum concentration of amino-groups (31.58 nmole/cm2) can be obtained from the plasma-polymerized sample at 80 W and 150 mTorr for 22 min. Moreover, the cell response also demonstrated that the allylamine plasma-modified Ti sample with an optimal modification parameter (80 W, 22 min, and 150 mTorr) possessed great potential to increase cell adhesion ability. Thus, the optimal parameters of the low-temperature plasma polymerization with allylamine can be harvested using the RSM design. These data could provide new scientific information in the surface modification of Ti implant. [ABSTRACT FROM AUTHOR]

We report here the dry, one-step, and low-temperature modification of FTO surfaces using pulsed plasma polymerization of allylamine (PPAAm). PPAAm/FTO surfaces were characterized by X-ray photoelectron spectroscopy, spectroscopic ellipsometry, and contact angles to understand the morphological, structural, and optical properties. FTO were coated with a very thin layer of adherent cross-linked, pinhole-, and additive-free allylamine plasma polymer resistant to hydrolysis and delamination, and characterized by a high density of positively charged amino groups. Electrochemical studies revealed that PPAAm/FTO electrodes show wide range pH stability and reaction rates tuned by the duration of plasma treatment. We show how the modification of plasma treatment duration between 72 s and 288 s affects the chemical structure and thickness of the obtained modification, having a strong influence on the charge transfer kinetics. In particular, XPS revealed the occurrence of the reduction processes under long-term plasma exposure proving the need for monitoring of this key factor. This covalent immobilization of amine compounds on FTO surface using rapid process in microwave pulsed-plasma makes it a promising electrode for future applications in electrochemical biosensors and optoelectronic devices. Image 107171 [ABSTRACT FROM AUTHOR]

Highlights • Acid, amine and oxazoline coated magnetic nanoparticles remove haze proteins. • Proteins in wine can bind to both negatively and positively charged nanoparticles. • Protein capture efficiency decreases in order: carboxyl > oxazoline > amine. • Plasma treatment and polymer coating do not affect crystallinity of nanoparticles. Abstract Magnetic nanoparticles were modified by plasma polymerization, using allylamine, acrylic acid and 2-methyl-2-oxazoline as precursor to produce amine, carboxyl and oxazoline functional group rich surfaces. The nanoparticles were characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and zeta potential measurements. The capacity of nanoparticles carrying different surface properties to remove haze-forming proteins from Sémillon and Sauvignon Blanc unfined wines was examined by high-performance liquid chromatography (HPLC). The protein capture efficiency of the modified surfaces decreases in the following order: COOH > POx > NH 2. This study will help optimising the design of this new technology for the selective removal of haze proteins from white wines. [ABSTRACT FROM AUTHOR]

Nucleophilic substitution on hexachlorocyclotriphosphazene (HCCTP) with allylamine in order to give hexa(allylamino)cyclotriphosphazene (HACTP) is performed for the first time under mild conditions by using diethylether as solvent to replace benzene which is very toxic. The reaction time is reduced to half and also performed at room temperature but especially in the presence of an eco-catalyst called Maghnite-H+. This catalyst has a significant role in the industrial scale. In fact, the use of Maghnite is preferred for its many advantages: a very low purchase price compared to other catalysts, the easy removal of the reaction mixture. Then, Maghnite-H+ is became an excellent catalyst for many chemical reactions. The structure of HACTP synthesized in the presence of Maghnite-H+ to 5% by weight is confirmed by 1H-NMR, 13C-NMR, 31P-NMR (Nuclear magnetic resonance) and FTIR (Fourier Transform Infrared spectroscopy). MALDI-TOF (Matrix-Assisted Laser Desorption/Ionisation-time-of-flight mass spectrometry) is used to establish the molecular weight of HACTP which is 471 g/mol. DSC (Differential Scanning Calorimetery) and TGA (Thermogravimetric Analysis) show that HACTP is a crystalline product with a melting point of 88 °C. It is reactive after melting but is degraded from 230 °C.

Abstract To remove Cr(VI) from aqueous solution, a macroporous poly glycidyl methacrylate- co - ethylene glycol dimethacrylate (poly(GMA- co -EGDMA)) adsorbent was synthesized by radical suspension copolymerization. Allylamine was used to open the epoxy ring of the prepared copolymer, then the radical polymerization of the grafted allylamine was performed, and as the last step, methyl isothiocyanate (MITC) was reacted with the crosslinked graft copolymers to introduce the thiourea groups. The introduced amine and thiourea functional groups enabled the effective removal of Cr(VI). The polymer was analyzed by FT-IR spectroscopy, FE-SEM, and mercury porosimetry, and the chemical structure, surface morphology and pore characteristics of the polymer were confirmed. The pH of the Cr(VI) solution strongly affected the performance of the adsorbent, and the best removal efficiency was obtained at pH 2. In the kinetic studies, the q e value determined from the pseudo-second-order model was similar to the experimental q e value, and this model showed the best correlation. The isotherm data were better fit by the Langmuir adsorption isotherm model than the Freundlich isotherm model, and the maximum adsorption capacity was 166.24 mg/g. [ABSTRACT FROM AUTHOR]

The first example of an unusual addition of chromone‐substituted acrylic acid to enamines is described. The process shows high versatility concerning both enamines and chromones. The reaction is catalyzed by tertiary amines and is highly likely of Morita–Baylis–Hillman‐type. The described compounds show combined moderate inhibitory action on BChE and antagonism towards NMDA receptors which makes them a perspective group for the development of anti‐Alzheimer drugs. An unusual addition of enamines to chromone‐substituted acrylic acid is an efficient and versatile method of synthesis of allylamine derivatives. The reaction is catalyzed by amines and is highly likely of Morita–Baylis–Hillman‐type. The described compounds show combined moderate inhibitory action on BChE and antagonism towards NMDA receptors [ABSTRACT FROM AUTHOR]

Graphical abstract Four halogenated Schiff base compounds were synthesized by reaction of halogenated salicylaldehydes (3,5-dichlorosalicylaldehyde, 3,5-dibromosalicylaldehyde, 3,5-diiodosalicylaldehyde and 3-bromo-5-chlorosalicylaldehyde) with allyl amine in water as green solvent at ambient temperature. Their Cu(II) Schiff base complexes showed halogen-halogen, π–π, CH–π interactions and also metal–halogen secondary bonds in crystal packing. These interactions investigated by Hirshfeld surface analysis and theoretical calculations. Abstract Although numerous Schiff base complexes have been synthesized and characterized, reports on Schiff base ligands and complexes derived from amines containing terminal allyl group are rare. In this work, four halogenated Schiff base compounds were synthesized by reaction of halogenated salicylaldehydes (3,5-dichlorosalicylaldehyde, 3,5-dibromosalicylaldehyde, 3,5-diiodosalicylaldehyde and 3-bromo-5-chlorosalicylaldehyde) with allyl amine in water as green solvent at ambient temperature and characterized by elemental analyses, NMR (1H and 13C), and FT-IR spectroscopy. In continue, their Cu(II) complexes were synthesized and characterized by elemental analyses, FT-IR and single-crystal X-ray diffraction. All complexes show halogen-halogen, π–π, CH–π interactions and also metal–halogen secondary bonds in crystal packing. The coordination geometry around the Cu(II) in all reported compounds is best described as square planar with two axially elongated interactions named metal–halogen secondary bond (Cu...X), all beyond the sum of the corresponding vdW radii (3.421 Å for Cu...Cl in (Cl 2 L) 2 Cu , 3.463 Å for Cu...Br in (Br 2 L) 2 Cu , 3.486 Å for Cu...I in (I 2 L) 2 Cu and 3.467 Å for Cu...Cl in (BrClL) 2 Cu). The crystal structures have also been subjected to Hirshfeld surface analysis which reveals that approximately most of the close contacts correspond to relatively weak interactions. Also, all of the interactions in crystal packing have been analyzed by theoretical calculations. [ABSTRACT FROM AUTHOR]

Abstract: Functionalizing medical devices with polypeptides to enhance their performance has become important for improved clinical success. The extracellular matrix (ECM) adhesion protein vitronectin (VN) is an effective coating, although the chemistry used to attach VN often reduces its bioactivity. In vivo, VN binds the ECM in a sequence‐dependent manner with heparan sulfate (HS) glycosaminoglycans. We reasoned therefore that sequence‐based affinity chromatography could be used to isolate a VN‐binding HS fraction (HS9) for use as a coating material to capture VN onto implant surfaces. Binding avidity and specificity of HS9 were confirmed by enzyme‐linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR)‐based assays. Plasma polymerization of allylamine (AA) to tissue culture‐treated polystyrene (TCPS) was then used to capture and present HS9 as determined by radiolabeling and ELISA. HS9‐coated TCPS avidly bound VN, and this layered surface supported the robust attachment, expansion, and maintenance of human pluripotent stem cells. Compositional analysis demonstrated that 6‐O‐ and N‐sulfation, as well as lengths greater than three disaccharide units (dp6) are critical for VN binding to HS‐coated surfaces. Importantly, HS9 coating reduced the threshold concentration of VN required to create an optimally bioactive surface for pluripotent stem cells. We conclude that affinity‐purified heparan sugars are able to coat materials to efficiently bind adhesive factors for biomedical applications. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1887–1896, 2018. [ABSTRACT FROM AUTHOR]

Abstract: We have performed three distinct plasma enhanced chemical vapor deposition procedures that can be widely and consistently used in commercially available plasma systems to modify the surface of hydrocarbon‐based biomaterials such as polypropylene. In particular, we have evaluated the feasibility of these procedures to provide consistent and stable charged substrates to perform layer‐by‐layer (LbL) coatings. Surface characterization of both plasma and LbL coatings were done using X‐ray photoelectron spectroscopy, attenuated total reflection—Fourier transform infrared spectroscopy, contact angle measurements and surface staining. Results showed successful surface grafting of functional groups in all plasma procedures that led to increased hydrophilicity and uniform LbL coatings with different efficiencies. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2078–2085, 2018 [ABSTRACT FROM AUTHOR]

In this work, a dielectric barrier discharge (DBD) has been used for the deposition of bipolar films containing alternating nano-layers of plasma polymerized allylamine (PPAam) and acrylic acid (PPAac). Various films were obtained by varying the single-layer thickness of each plasma polymer while maintaining a constant total film thickness and two kinds of films were fabricated via different depositing sequences (PPAam/Aac and PPAac/Aam). Films properties, ageing in air and stability in water over a 7 days period were investigated. Results showed that, COO − and NH 3 + polar entities, generated from the interaction of PPAam and PPAac, are present in the bipolar films. Concerning the films stability, the different reaction mechanisms involved in the formation of each kind of films resulted in a higher amount of polar groups in the PPAam/Aac films; this conferred these films a higher stability than PPAac/Aam. Concerning the films ageing behavior, all prepared samples underwent some kind of ageing which was found to be dependent on the deposition sequence. Results also showed that bipolar coatings exhibited better cell-material interactions compared to PPAam and PPAac films; with a better cell viability observed on PPAam/Aac coatings after 1 and 7 days culture. [ABSTRACT FROM AUTHOR]

Colloidal assemblies represent a versatile and cost efficient way to generate surface patterns at micron and sub-micron length scales. Chemical modification of the assemblies can be utilized to study the influence of different surface chemistries on cellular responses with high lateral resolution. In this study, single and binary colloidal assemblies were made using different sizes of particles. An allylamine plasma polymer (ALApp) layer was deposited on the top of the assemblies to provide a uniform surface chemistry. Cellular responses toward unmodified and ALApp-coated assemblies was evaluated using L929 fibroblasts. Cells showed smaller spreading area on both single and binary assemblies compared to flat control. Cell size was dependent on the particle size or combination. This effect can be compensated by different degrees after the ALApp coating. These results will find application in the development of new cell culture coatings through the combined use of colloidal assembles and plasma polymer coatings. [ABSTRACT FROM AUTHOR]

This study developed a promising approach (low-temperature plasma polymerization with allylamine) to modify the titanium (Ti) surface, which helps the damaged tissue to heal faster. The Ti surface was first cleaned by argon (Ar) plasma, and then the functional amino-groups were coated on the Ti surface via plasma polymerization. The topography characteristics, wettability, and optimal plasma modification parameters were investigated through atomic force spectroscopy, secondary ion mass spectroscopy, and response surface methodology (RSM). Analytical results showed that the formation of a porous surface was found on the Ar plasma-modified Ti surfaces after Ar plasma modification with different parameters. The Ar plasma modification is an effective approach to remove surface contaminants and generate a porous topography on the Ti surface. As the Ti with Ar plasma modification was at 100 W and 190 m Torr for 12 min, the surface exhibited the maximum hydrophilic performance. In the allylamine plasma modifications, the contact angle values of the allylamine plasma-modified Ti surfaces varied between 70.15° and 88.26° in the designed parameters. The maximum concentration of amino-groups (31.58 nmole/cm2) can be obtained from the plasma-polymerized sample at 80 W and 150 mTorr for 22 min. Moreover, the cell response also demonstrated that the allylamine plasma-modified Ti sample with an optimal modification parameter (80 W, 22 min, and 150 mTorr) possessed great potential to increase cell adhesion ability. Thus, the optimal parameters of the low-temperature plasma polymerization with allylamine can be harvested using the RSM design. These data could provide new scientific information in the surface modification of Ti implant.

The effect of ionic strength and pH on the structure of hydrated plasma polymerized films of allylamine (ppAAm) and acrylic acid (ppAAc) has been analyzed in situ using quartz crystal microbalance with dissipation techniques, electrochemical impedance spectroscopy, ellipsomtery, and X-ray photoelectron spectroscopy. Both materials showed a salt concentration and pH dependent uptake and release of water and ions. Depending on the type of monomer used, the effects showed reversible or non-reversible behavior. The investigation of the electrochemical properties of the film further revealed a non-homogeneous structure, especially in the case of ppAAc films, with regions of higher and lower cross-linking density. The use of complimentary techniques to characterize the films in situ allowed for a deeper understanding of processes happening inside the plasma polymerized films, which can help to optimize film preparation conditions for selected applications. [ABSTRACT FROM AUTHOR]

The first asymmetric synthesis of important α,α-disubstituted N-alkyl allyl amine scaffolds through allylic substitution is reported. This approach is based on palladium catalysis and features ample scope with respect to both the allylic precursor and amine reagent, and high asymmetric induction with enantiomeric ratios (e.r.) up to 98.5:1.5. The use of less-reactive anilines is also feasible, providing enantioenriched α,α-disubstituted N-aryl allylic amines. [ABSTRACT FROM AUTHOR]

In this work, a dielectric barrier discharge (DBD) operated at medium to atmospheric pressure has been used for the deposition of thin polyallylamine (PAA) films on ultra-high molecular weight polyethylene (UHMWPE) substrates. The effect of treatment time (1–5 min), discharge power (5.7–24.0 W), monomer concentration (1–2 g/h) and pressure (10–100 kPa) on the films properties, aging and stability behaviors have been investigated. The used characterization techniques are X-ray photoelectron spectroscopy, water contact angle and optical reflectance spectroscopy. In this paper, it is shown that plasma treatment time does not affect the coatings chemistry; whereas plasma power, monomer concentration and pressure control the coatings properties. It is also shown that the deposition rate of the deposited films changes with varying W / FM values. At low W / FM values, high deposition rates of up to 2 nm/s are observed. Plasma treatments were also characterized by their amino efficiency ([NH 2 ]/[C] in %) and amino selectivity ([NH 2 ]/[N] in %). Depending on the used parameters, these varied between 12.3% and 20% and between 71.2% and 91.1%, respectively. For the aging study, coatings that preserved most of their hydrophilicity were obtained at power ≤11.3 W, monomer concentration ≥1.5 g/h and pressure ≥50 kPa. For the stability study, coatings that showed the highest [N] (%) and lowest percentage of thickness decrease were obtained at ≤2 min, 24.0 W, 1 g/h and pressure ≤50 kPa. One can therefore control the deposition rate as well as the properties, aging and stability behaviors of the deposited coating by carefully choosing the plasma parameters. [ABSTRACT FROM AUTHOR]

Designing effective drug nanocarriers that are easy to synthesize, robust, and nontoxic is a significant challenge in nanomedicine. Polyamine-multivalent molecule nanocomplexes are promising drug carriers due to their simple and all-aqueous manufacturing process. However, these systems can present issues of colloidal instability over time and cellular toxicity due to the cationic polymer. In this study, we finely modulate the formation parameters of poly(allylamine-tripolyphosphate) complexes to jointly optimize the robustness and safety. Polyallylamine was ionically assembled with tripolyphosphate anions to form liquid-like nanocomplexes with a size of around 200 nm and a zeta potential of -30 mV. We found that nanocomplexes exhibit tremendous long-term stability (9 months of storage) in colloidal dispersion and that they are suitable as protein-loading agents. Moreover, the formation of nanocomplexes induced by tripolyphosphate anions produces a switch-off in the toxicity of the system by altering the overall charge from positive to negative. In addition, we demonstrate that nanocomplexes can be internalized by bone-marrow-derived macrophage cells. Altogether, these nanocomplexes have attractive and promising properties as delivery nanoplatforms for potential therapies based on the immune system activation.

Adherence to antifungals is poor in high endemic regions where antifungal resistance is high. Poor readability of prescription/over-the-counter (OTC) antifungals may contribute to poor adherence, due to the patient not fully understanding the purpose, importance, and dosage of their antifungal medicine. As there are no reports on the readability of antifungals, this study examined the readability of patient-facing antifungal information. Antifungals (n = 16; five classes [allylamines, azoles, echinocandins, polyenes, and others-flucytosine and griseofulvin]) were selected. Readability of four sources of information, (i) summary of product characteristics, (ii) patient information leaflets (PILs), (iii) OTC patient information, and (iv) patient web-based information, was calculated using Readable software, to obtain readability scores [(i) Flesch Reading Ease [FRE], (ii) Flesch-Kinkaid Grade Level [FKGL], (iii) Gunning Fog Index, and (iv) Simple Measure of Gobbledygook (SMOG) Index) and text metrics [word count, sentence count, words/sentence, and syllables/word]. PILs, web-based resources, and OTC patient information had good readability (FRE mean ± sd = 52.8 ± 6.7, 58.6 ± 6.9, and 57.3 ± 7.4, respectively), just falling short of the ≥ 60 target. For FKGL (target ≤ 8.0), PILs, web-based resources, and OTC patient information also had good readability (mean ± sd = 8.5 ± 1.0, 7.2 ± 0.86, and 7.8 ± 0.1, respectively). Improved readability scores observed correlate with reduced words, words/sentence and syllables/word. Improving readability may lead to improved patient health literacy. Healthcare professionals, academics, and publishers preparing written materials regarding antifungals for the lay/patient community are encouraged to employ readability calculators to check the readability of their work, so that the final material is within recommended readability reference parameters, to support the health literacy of their patients/readers., (© The Author(s) 2023. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

A concise route for the preparation of two simple optically pure indolizidin-5-ones has been developed. The key chain elongation process was achieved using a triethylborane/catechol mediated hydroalkylation of Boc-protected 2-vinylpyrrolidines. By using complementary strategies, these two bicyclic lactams can be alkylated with complete control of the stereochemistry at C(5) and their conversion to a variety of indolizidine alkaloids such as coniceine, indolizidine 209D and 167B, 5-epi-indolizidine 249A and monomorine has been reported in the literature. [ABSTRACT FROM AUTHOR]

Pseudoaspidinol is a phloroglucinol derivative with Antifungal activity and is a major active component of Dryopteris fragrans. In our previous work, we studied the total synthesis of pseudoaspidinol belonging to a phloroglucinol derivative and investigated its antifungal activity as well as its intermediates. However, the results showed these compounds have low antifungal activity. In this study, in order to increase antifungal activities of phloroglucinol derivatives, we introduced antifungal pharmacophore allylamine into the methylphloroglucinol. Meanwhile, we remained C1⁻C4 acyl group in C-6 position of methylphloroglucinol using pseudoaspidinol as the lead compound to obtain novel phloroglucinol derivatives, synthesized 17 compounds, and evaluated antifungal activities on Trichophyton rubrum and Trichophyton mentagrophytes in vitro. Molecular docking verified their ability to combine the protein binding site. The results indicated that most of the compounds had strong antifungal activity, in which compound 17 were found to be the most active on Trichophyton rubrum with Minimum Inhibitory Concentration (MIC) of 3.05 μg/mL and of Trichophyton mentagrophytes with MIC of 5.13 μg/mL. Docking results showed that compounds had a nice combination with the protein binding site. These researches could lay the foundation for developing antifungal agents of clinical value.

The determination of clinically significant amounts of tau protein in bodily fluids is a major problem in Alzheimer's disease (AD) diagnosis. As a result, the present work aims to develop a simple, label-free, fast, highly sensitive, and selective 2D carbon backbone graphene oxide (GO) patterned surface plasmon resonance (SPR) mediated affinity biosensor for Tau-441 monitoring. Initially, non-plasmonic nanosized GO was made using a modified Hummers' method, whereas green synthesized gold nanoparticles (AuNPs) were subjected to a layer-by-layer (LbL) design employing anionic and cationic polyelectrolytes. Several spectroscopical evaluations were carried out to ensure the synthesis of GO, AuNPs, and LbL assembly. Following that, the Anti-Tau rabbit antibody was immobilized on the designed LbL assembly using carbodiimide chemistry, and various studies such as sensitivity, selectivity, stability, repeatability, spiked sample analysis, etc., were conducted using the constructed affinity GO@LbL-AuNPs-Anti-Tau SPR biosensor. As an output, it shows a broad concentration range and a very low detection limit of 150 ng/mL to 5 fg/mL and 13.25 fg/mL, respectively. The remarkable sensitivity of this SPR biosensor represents the merits of a combination of plasmonic AuNPs and a non-plasmonic GO. It also exhibits great selectivity for Tau-441 in the presence of interfering molecules, which may be because of the immobilization of the Anti-Tau rabbit on the surface of the LbL assembly. Furthermore, it ensured high stability and repeatability, while spiked sample analysis and AD-induced animal samples analysis confirmed the practicability of GO@LbL-AuNPs-Anti-Tau SPR biosensor for Tau-441 detection. In conclusion, fabricated sensitive, selective, stable, label-free, quick, simple, and minimally invasive GO@LbL-AuNPs-Anti-Tau SPR biosensor will provide an alternative for AD diagnosis in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Stereospecific α-amination has been accomplished via addition of N-phenyltriazolinedione (PhTAD) to the allylic position of dihydropyrroles. The aim of this study is to evaluate new PhTAD derivatives of biologically active bicyclic dihydropyrroles. Ene reaction was accomplished via addition of PhTAD to the allylic position to react with syn and anti diastereomers for α-amination. The α-amination depends on the stereochemistry, proceeding faster with syn than anti diastereoisomers. Steric hindrance from sulfide substituent slows down the transformation. Although the results are in accordance with an ene reaction followed by 1,3-shift of the urazole moiety, deuteration at the allylic position by simply stirring the diastereoisomeric dihydropyrroles in MeOD revealed a [1,3-H] shift. The stereospecificity of the transformation is attributed to steric hindrance during the allylic transposition step. [ABSTRACT FROM AUTHOR]

ABSTRACT The acyclic diene metathesis (ADMET) polymerization was utilized for the design of the ADMET polymer ( Mn = 21,200 g/mol, Mw/ Mn = 1.74) with pendant perfluorophenyl ester functionality using Grubbs first generation catalysis overnight in bulk at 80 °C. Next, a wide variety of functional groups, like benzyl, octyl, propargyl, allyl, and furfuryl was quantitatively incorporated to the ADMET polymer backbone through various amines using activated ester substitution reaction. The ADMET polymers studied in this work were characterized using 1H, 13C, and 19F NMR, GPC and DSC and displayed a monomodal distribution and a rather broad polydispersity index in the range of −1.33 to 1.90. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2593-2598 [ABSTRACT FROM AUTHOR]