Modification of Liposomal Properties by an Engineered Gemini Surfactant.

Lipid membranes form the primary structure of cell membranes and serve as configurable interfaces across numerous applications including biosensing technologies, antifungal treatments, and therapeutic platforms. Therefore, the modification of lipid membranes by additives has important consequences in both biological processes and practical applications. In this study, we investigated a nicotinic-acid-based gemini surfactant (NAGS) as a chemically tunable molecular additive for modulating the structure and phase behavior of liposomal membranes.

POPs to COFs by post-modification: CO chemisorption and dissolution.

Porous organic polymers (POPs) and covalent organic frameworks (COFs) are hierarchical nano materials with variable applications. To our knowledge, this is the first report of a post-modified, non-renewable, DMSO-soluble M-POP/1,8-diazabicyclo[5.4.

CS/CO Utilization Using Mukaiyama Reagent as a (Thio)carbonylating Promoter: A Proof-of-Concept Study.

We report on the reaction of ethylene-terminated heteroatoms (CX; X = N, O, and S) with CS/CO using Mukaiyama reagent (2-chloro-1-methylpyridinium iodide, CMPI) as a promoter for the preparation of imidazolidin-2-one, oxazolidin-2-one, 1,3-dioxolan-2-one, 1,3-dithiolan-2-one, and their thione counterparts at ambient temperature and pressure. Spectroscopic measurements, , H/C nuclear magnetic resonance (NMR) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy methods verified the reaction of CS/CO with the ethylene-based substrates and subsequently the formation of cyclic products. The experimental data indicated the formation of the -form of imidazolidin-2-one and oxazolidin-2-one, while the -form was obtained for their thione correspondents.

Interfacial Behavior of Modified Nicotinic Acid as Conventional/Gemini Surfactants.

We report the synthesis and monolayer properties of conventional and gemini surfactants composed of nicotinic acid-based head groups with an emphasis on assessing how chemical structures affect the behavior of monolayers. A combination of Brewster angle microscopy and atomic force microscopy showed that pure hexadecyl nicotinate formed rippled strands in monolayers, and the gemini correspondents with either flexible or rigid organic linkers resulted in lobed-compact domains, which provides a simple method for patterning air-water and solid-air interfaces. The structural differences between conventional and gemini nicotinic acid-based surfactants could be explained by the interplay between line tension (that favors the formation of circular domains), balanced by dipole-dipole repulsion interaction between headgroups, which promotes extended domains.

activation of green sorbents for CO capture upon end group backbiting.

Thermolysis of a urethane end group was observed as a first time phenomenon during activation. This unzipping mechanism revealed a new amine tethering point producing a diamine-terminated oligourea ([10]-OU), acting as a green sorbent for CO capturing. The oligomer backbites its end group to form propylene carbonate (PC), as proved by TGA-MS, which can reflect the polymer performance by maximizing its capturing capacity.

Chemisorption of CO by diamine-tetraamido macrocyclic motifs: a theoretical study.

Although alkanolamines have been systematically utilized for CO2 capture, intensive research efforts are still required to ultimately design more efficient CO2 sorbents with appropriate sorption characteristics. In this article, we have explored a series of diamine-tetraamido macrocyclic molecules with different organic linkers, namely, pyridine, phenylene, pyrrole, furan, and thiophene, for the titled purpose using quantum chemical calculations. The optimized structures of the sequestration reaction revealed the formation of a carbamate anion within the macrocyclic cavity that was stabilized through several intramolecular interactions compared to parent amines.

CO coupling with epoxides catalysed by using one-pot synthesised, in situ activated zinc ascorbate under ambient conditions.

An in situ generated zinc ascorbate pre-catalyst for cyclic carbonate (CC) synthesis via CO coupling with epoxides under ambient conditions was reported. Spectroscopic measurements indicated that CO was inserted into the zinc ascorbate complex through the formation of an activated zinc carbonate catalyst upon abstracting the enediol protons with sodium hydride. The aliphatic diols were not activated under the applied conditions and did not interfere with either the process of cycloaddition or CO activation.

The eternal battle to combat global warming: (thio)urea as a CO wet scrubbing agent.

(Thio)Urea scaffolds are best known for their importance as intermediates in organic synthesis. In this work, a mechanistic study of the reaction between urea (U), (2-hydroxyethyl)urea (U-EtOH) and thiourea (tU)/NaH in DMSO with CO2 was carried out. While both U/tU reacted with CO2via a 1 : 2 mechanism through the formation of the keto (thio)carbamide-carboxylate adducts (k-U/tU-CO2- Na+), U-EtOH gave mixed CO2-adducts composed of organic carbonate and carbamide-carboxylate moieties (Na+-CO2-U-Et-OCO2- Na+).

Encapsulation of ionic liquids inside cucurbiturils.

Cucurbit[n]urils (CBn, n = 6-8) serve as molecular receptors for imidazolium-based ionic liquids (ILs) in aqueous solution. The amphiphilic nature of 1-alkyl-3-methylimidazolium guests (Cnmim), with a cationic imidazolium residue and a hydrophobic alkyl chain, enabled their complexation with CBn through a combination of the hydrophobic effect and ion-dipole interactions. 1H NMR experiments revealed that the cavity of CBn can host the hydrophobic chain of the ILs, while one of the carbonyl rims served as a docking site for the imidazolium ring.

CO activation through C-N, C-O and C-C bond formation.

A comparative model for the chemisorption of CO was explored via three representative reaction pathways: carboxylation of cyclohexanone, carbonation of cyclohexanol, and carbamation of cyclohexylamine. The model substrates were activated using 1,8-diazabicyclo[5.4.

Biomaterials for CO Harvesting: From Regulatory Functions to Wet Scrubbing Applications.

A new series of 2-aminoethyl-benzene-based biomaterials, namely, dopamine (DOP), tyramine (TYR), phenylethylamine (PEA), and epinephrine (EPN), dissolved in dimethylsulfoxide (DMSO) have been investigated for CO capture upon activatiing their hydhydrochloride salts  with a NaOH pellet. Spectroscopic measurements, including ex situ ATR-FTIR, 1D and 2D NMR experiments have been applied to verify the formation of the sodium carbamate adducts (RR'N-CO Na). The emergence of new peaks in the IR spectra ranging between 1702 and 1735 cm together with the chemical shift within 157-158 ppm in the C NMR, as well as with cross-peaks obtained by H-N HSQC measurements at ca.

High-k Fluoropolymer Gate Dielectric in Electrically Stable Organic Field-Effect Transistors.

A detailed study of a high-k fluoropolymer gate dielectric material, poly(vinylidene fluoride- co-hexafluoropropylene) [P(VDF-HFP)], is presented as a guide to achieve low operational voltage and electrically stable device performance. The large dipole moment of C-F dipoles in P(VDF-HFP) is responsible for its high dielectric constant as well as its potentially ferroelectric behavior that must be minimized to avoid hysteretic current-voltage characteristics. A range of material grades and processing conditions are explored and are shown to have a significant effect on the degree of hysteresis observed in device-transfer characteristics.

A catecholamine neurotransmitter: epinephrine as a CO wet scrubbing agent.

Bio-renewables are emerging as potential materials for CO2 sorption. Epinephrine is employed as a green scrubbing agent for CO2 capturing through the formation of a metal carbamate as proved by 1H, 13C and 1H-15N NMR and ex situ ATR-FTIR spectroscopy, as well as supported by quantum-chemical calculations.

A green sorbent for CO capture: α-cyclodextrin-based carbonate in DMSO solution.

Cyclodextrin (α-CD)/KOH pellet dissolved in DMSO was utilized to capture CO. KOH has a dual function of enhancing the nucleophilicity of the hydroxyl groups on the α-CD rims and acting as a desiccant. C NMR spectroscopy provided evidence for the chemisorption of CO through the formation of organic carbonate (RO-CO ·K).

Inedible saccharides: a platform for CO capturing.

The economic viability of eco-friendly and renewable materials promotes the development of an alternative technology for climate change mitigation. Investigations reported over the past few years have allowed understanding the mechanism of action for a wide spectrum of saccharides toward carbon dioxide (CO), in terms of reactivity, reversibility, stability and uptake. Exploiting bio-renewables, , inedible saccharides, to reduce the anthropogenic carbon footprint upon providing a sustainable and promising technology that is of interest to different groups of scientists, to overcome demerits associated with the current state-of-the-art aqueous amine scrubbing agents, following a "green chemistry guideline", by employing materials with properties relevant to the environment toward sustainable development.

Phase-separated surfactant monolayers: Exploiting immiscibility of fluorocarbons and hydrocarbons to pattern interfaces.

The mutual immiscibility of hydrogenated and fluorinated surfactants at interfaces frequently leads to phase-separation, which provides a useful and flexible method for patterning air-water and solid-air interfaces. In this article, we review recent advances in the use of hydrogenated-fluorinated surfactant mixtures to achieve interfacial patterning. For even relatively simple systems comprised of binary mixed monolayers of hydrogenated and perfluorinated fatty acids, a diverse range of film morphologies can be generated at the air-water interface and successfully transferred onto solid substrates.

New insights into the chemistry of ionic alkylorganic carbonates: a computational study.

A library of hydrogenated, perfluorinated aliphatic and aromatic (p-substituted) alcohols are selected together with a combination of superbases (SBs) and metal hydrides (MHs) to understand the thermodynamic parameters of the binary mixtures once serving as sorbents for the capture of COvia ionic organic alkyl-carbonate (RCO) formation. Data are obtained using density functional theory (DFT) calculations with the B3LYP/6-31+G* level of theory and compared with the experimental results acquired from the literature using different spectroscopic techniques. It is found that the capturing process has a favourable enthalpic contribution and an unfavourable entropic penalty regardless the identity of the base, where the enthalpy values of alcohol/MH binary mixtures are almost two-fold higher compared to their SB-based mixtures.

An investigation of carbon dioxide capture by chitin acetate/DMSO binary system.

Chitin is considered to be the second most abundant naturally-occurring polysaccharide. Also, dimethyl sulfoxide (DMSO) is the second highest dielectric constant polar solvent after water. Despite the low solubility of chitin in common organic solvents, and due to its high nitrogen content, it may serve as a potential scrubbing agent "wet scrubbing" for carbon dioxide (CO2) capturing as an alternative to monoethanolamine "renewables for renewables approach".

Exploring the Impact of Tail Polarity on the Phase Behavior of Single Component and Mixed Lipid Monolayers Using a MARTINI Coarse-Grained Force Field.

Coarse-grained molecular dynamics simulations have been used to investigate the effect of dipalmitoylphosphatidylcholine (DPPC) tail group polarity on the structural and phase behavior of both single component and binary mixed monolayers using the MARTINI force field. Surface pressure-area isotherms of single component systems indicate that DPPC monolayers become more expanded as a function of increasing tail group polarity, as observed in experimental measurements in the literature. A combination of radial distribution functions and tilt angle measurements indicate that increasing tail group polarity results in the formation of increasingly disordered monolayers.

Understanding the morphology of solution processed fullerene-free small molecule bulk heterojunction blends.

Bulk-heterojunction (BHJ) molecular blends prepared from small molecules based on diketopyrrolopyrrole (DPP) and perylene-diimide (PDI) chromophores have been studied using optical absorption, cyclic voltammetry, photoluminescence quenching, X-ray diffraction, atomic force microscopy, and current-voltage measurements. The results provided useful insights into the use of DPP and PDI based molecules as donor-acceptor composites for organic photovoltaic (OPV) applications. Beside optoelectronic compatibility, the choice of active layer processing conditions is of key importance to improve the performance of BHJ solar cells.

Influence of film composition on the morphology, mechanical properties, and surfactant recovery of phase-separated phospholipid-perfluorinated fatty acid mixed monolayers.

Monolayer surfactant films composed of a mixture of phospholipids and perfluorinated (or partially fluorinated) surfactants are of potential utility for applications in pulmonary lung surfactant-based therapies. As a simple, minimal model of such a lung surfactant system, binary mixed monolayer films composed of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and perfluorooctadecanoic acid (C18F) prepared on a simplified lung fluid mimic subphase (pH 7.4, 150 mM NaCl) have been characterized in terms of mixing thermodynamics and compressibility (measured through π–A compression isotherms), film morphology (via atomic force, fluorescence, and Brewster angle microscopy), as well as spreading rate and hysteresis response to repeated expansion–contraction cycles for a variety of compositions of mixed films.

Phase-separation of mixed surfactant monolayers: a comparison of film morphology at the solid-air and liquid-air interfaces.

The morphologies of phase-separated monolayer films prepared from two different binary mixtures of perfluorocarbons and hydrocarbons have been examined and compared, for the first time, at the solid-air and liquid-air interfaces. Films were comprised of binary mixtures of arachidic acid (C(19)H(39)COOH) with perfluorotetradecanoic acid (C(13)F(27)COOH) and of palmitic acid (C(15)H(31)COOH) with perfluorooctadecanoic acid (C(17)F(35)COOH). For both mixed systems, Langmuir Blodgett films on mica substrates consisted of polygonal domains of one surfactant dispersed in a continuous matrix of the other (arachidic acid in perfluorotetradecanoic acid or perfluorooctadecanoic acid in palmitic acid, respectively), consistent with previous reports.

Thermodynamic and structural characterization of a mixed perfluorocarbon-phospholipid ternary monolayer surfactant system.

Pulmonary lung surfactant is a mixture of surfactants that reduces surface tension during respiration. Perfluorinated surfactants have potential applications for artificial lung surfactant formulations, but the interactions that exist between these compounds and phospholipids in surfactant monolayer mixtures are poorly understood. We report here, for the first time, a detailed thermodynamic and structural characterization of a minimal pulmonary lung surfactant model system that is based on a ternary phospholipid-perfluorocarbon mixture.

The influence of salinity on surfactant miscibility in mixed dipalmitoylphosphatidylcholine-perfluorooctadecanoic acid monolayer films.

The miscibility, mechanical and morphological properties of mixed Langmuir and Langmuir-Blodgett monolayers prepared from the phospholipid 1,2-dipalmitoyl-sn-glycero-3-phosphocholine and the perfluorinated fatty acid perfluorooctadecanoic acid have been studied as a function of film composition and subphase salinity. It was demonstrated here, for the first time, that the extent of surfactant miscibility in mixed phospholipid-perfluoroacid monolayers, and hence the resulting mechanical properties of the monolayer film, can be controlled by altering the concentration of sodium ions in the underlying subphase. Elevated Na(+) concentrations resulted in lower net attractive interactions between film components, likely through specific ion adsorption to the negatively-charged perfluoroacid, along with decreased film elasticities.