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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]

PurposeTo explore the cross-sectional and longitudinal relationships between fractional liver fat content, liver volume, and total liver fat burden.MethodsIn 43 adults with non-alcoholic steatohepatitis participating in a clinical trial, liver volume was estimated by segmentation of magnitude-based low-flip-angle multiecho GRE images. The liver mean proton density fat fraction (PDFF) was calculated. The total liver fat index (TLFI) was estimated as the product of liver mean PDFF and liver volume. Linear regression analyses were performed.ResultsCross-sectional analyses revealed statistically significant relationships between TLFI and liver mean PDFF (R 2 = 0.740 baseline/0.791 follow-up, P < 0.001 baseline/P < 0.001 follow-up), and between TLFI and liver volume (R 2 = 0.352/0.452, P < 0.001/< 0.001). Longitudinal analyses revealed statistically significant relationships between liver volume change and liver mean PDFF change (R 2 = 0.556, P < 0.001), between TLFI change and liver mean PDFF change (R 2 = 0.920, P < 0.001), and between TLFI change and liver volume change (R 2 = 0.735, P < 0.001).ConclusionLiver segmentation in combination with MRI-based PDFF estimation may be used to monitor liver volume, liver mean PDFF, and TLFI in a clinical trial.

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]

UnlabelledBile acid sequestrants (BAS) lower plasma low density lipoprotein levels and improve glycemic control. Colestimide, a BAS, has been claimed by computed tomography to reduce liver fat. Therefore, we examined the efficacy of colesevelam, a potent BAS, to decrease liver fat in patients with biopsy-proven nonalcoholic steatohepatitis (NASH). Liver fat was measured by a novel magnetic resonance imaging (MRI) technique, the proton-density-fat-fraction (PDFF), as well as by conventional MR spectroscopy (MRS). Fifty patients with biopsy-proven NASH were randomly assigned to either colesevelam 3.75 g/day orally or placebo for 24 weeks. The primary outcome was change in liver fat as measured by MRI-PDFF in colocalized regions of interest within each of the nine liver segments. Compared with placebo, colesevelam increased liver fat by MRI-PDFF in all nine segments of the liver with a mean difference of 5.6% (P = 0.002). We cross-validated the MRI-PDFF-determined fat content with that assessed by colocalized MRS; the latter showed a mean difference of 4.9% (P = 0.014) in liver fat between the colesevelam and the placebo arms. MRI-PDFF correlated strongly with MRS-determined hepatic fat content (r(2) = 0.96, P < 0.0001). Liver biopsy assessment of steatosis, cellular injury, and lobular inflammation did not detect any effect of treatment.ConclusionColesevelam increases liver fat in patients with NASH as assessed by MRI as well as MRS without significant changes seen on histology. Thus, MRI and MRS may be better than histology to detect longitudinal changes in hepatic fat in NASH. Underlying mechanisms and whether the small MR-detected increase in liver fat has clinical consequences is not known.

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.