Influence Of Chain Length Research Articles

Organic Acid‐Assisted Preparation of Hydroxyapatite‐supported Ni Catalysts for Arene Hydrogenation

Developing non‐noble metal catalysts that can efficiently and selectively hydrogenate arenes remains a significant challenge. In this study, we developed efficient Ni catalysts for the arene hydrogenation based on an organic acid‐regulated impregnation strategy. These easily accessible Ni catalysts demonstrated exceptional efficiency, selectivity, reusability, and good substrate compatibility. The influence of carbon chain lengths and side‐chain hydroxyl or amino groups on dicarboxylic acids used in the catalyst preparation was comprehensively investigated. Characterizations and kinetic studies demonstrated the influence of organic acids on the size of Ni nanoparticles, the proportion of metallic nickel, and the strength of surface acidity. These factors influenced the activation of arene and hydrogen, thereby affecting the hydrogenative activity. Notably, hydroxyapatite‐supported Ni catalyst, assisted by tartaric acid (Ni‐TA/HAP) with an appropriate tartaric acid‐to‐nickel ratio, resulted in relatively smaller Ni nanoparticles, an increased proportion of Ni0, and more acidic sites, thereby exhibiting the best hydrogenation performance.

Unveiling the Influence of Organic Chain Length on the Physical Properties of Two-Dimensional Cobalt-Based Hybrid Perovskites

Unveiling the Influence of Organic Chain Length on the Physical Properties of Two-Dimensional Cobalt-Based Hybrid Perovskites

Influence of Temperature, Anions, and Alkyl Chain Length on the Density, Viscosity, Speed of Sound, Surface Tension, and Refractive Index of Imidazolium Hexafluorophosphate-Based Ionic Liquids

Influence of Temperature, Anions, and Alkyl Chain Length on the Density, Viscosity, Speed of Sound, Surface Tension, and Refractive Index of Imidazolium Hexafluorophosphate-Based Ionic Liquids

Transport properties of ethylene glycol functionalized membranes exposed to nonaqueous electrolytes

Non-aqueous redox flow batteries (RFBs) are a promising technology to meet growing demand for grid-scale energy storage. Membrane separators, designed specifically for use with organic solvents, are necessary to advance non-aqueous RFBs. Herein, we report the development of a series of poly(phenylene oxide) (PPO) membranes functionalized with poly(ethylene glycol) (PEG) side chains to investigate the influence of PEG side chain length and degree of PEGylation on membrane transport properties. Increasing the degree of PEGylation generally led to increases in electrolyte uptake, hydroxy TEMPO permeability, and ionic conductivity likely caused by an increase in overall PEG content, as opposed to specific interactions caused by changing the degree of PEGylation. For membranes with similar PEG content, increasing the length of the PEG side chain resulted in decreases in electrolyte uptake, permeability, and conductivity possibly due to differences in the solvation behavior of the PEG chains with different lengths.

Pre-Polymer Chain Length: Influence on Permanent Memory Effect of PDLC Devices

This study delved into the correlation between the chain length of PEG polymerizable oligomers and the electro-optical properties exhibited by the resultant PDLC films. A range of di(meth)acrylate oligomers derived from polyethylene glycol with varying molecular weights (Mn = 1000, 2000, 4000, and 6000 g mol−1) was synthesized for incorporation as the polymer matrix in PDLC devices. Comprehensive analyses employing 1H-NMR, 13C-NMR, and MALDI-TOF mass spectroscopy were conducted to validate the structure and purity of the synthesized products. The investigation revealed a significant influence of pre-polymer molecular chain length on the thermal properties of the polymer, including amorphousness and crystallinity, which in turn impact the permanent memory effect. Specifically, it was observed that amorphous PEG polymers serve as an ideal matrix for fostering the permanent memory effect in PDLCs. Among the polymerizable PEG oligomers examined, those with a molecular weight of 1000 g/mol yielded polymer chains existing in an amorphous state, exhibiting a glass transition temperature lower than room temperature (−50 °C). This characteristic imparts flexibility and mobility to the polymer matrix chains, facilitating a 37% permanent memory effect. Conversely, longer polymer chains lead to the formation of crystal aggregates, resulting in semi-crystalline polymer matrices. This reduces the malleability of the polymer chains, thereby nullifying the permanent memory effect in the corresponding PDLC devices.

Improving Gene Delivery: Synergy between Alkyl Chain Length and Lipoic Acid for PDMAEMA Hydrophobic Copolymers.

In the field of gene delivery, hydrophobic cationic copolymers hold great promise. They exhibit improved performance by effectively protecting genetic material from serum interactions while facilitating interactions with cellular membranes. However, managing cytotoxicity remains a significant challenge, prompting an investigation into suitable hydrophobic components. A particularly encouraging approach involves integrating nutrient components, like lipoic acid, which is known for its antioxidant properties and diverse cellular benefits such as cellular metabolism and growth. In this study, a copolymer library comprising 2-(dimethylamino)ethyl methacrylate (DMAEMA) and lipoic acid methacrylate (LAMA), combined with either n-butyl methacrylate (nBMA), ethyl methacrylate (EMA), or methyl methacrylate (MMA), is synthesized. This enables to probe the impact of lipoic acid incorporation while simultaneously exploring the influence of pendant acyclic alkyl chain length. The inclusion of lipoic acid results in a notable boost in transfection efficiency while maintaining low cytotoxicity. Interestingly, higher levels of transfection efficiency are achieved in the presence of nBMA, EMA, or MMA. However, a positive correlation between pendant acyclic alkyl chain length and cytotoxicity is observed. Consequently, P(DMAEMA-co-LAMA-co-MMA), emerges as a promising candidate. This is attributed to the optimal combination of low cytotoxic MMA and transfection-boosting LAMA, highlighting the crucial synergy between LAMA and MMA.

Using asymmetric giant unilamellar vesicles to investigate the influence of low-melting phospholipid chain length on interleaflet coupling of phase behavior

Using asymmetric giant unilamellar vesicles to investigate the influence of low-melting phospholipid chain length on interleaflet coupling of phase behavior

Unveiling the role of linear alkyl organic cations in 2D layered tin halide perovskite field-effect transistors.

Two-dimensional (2D) tin halide perovskites are promising semiconductors for field-effect transistors (FETs) owing to their fascinating electronic properties. However, the correlation between the chemical nature of organic cations and charge carrier transport is still far from understanding. In this study, the influence of chain length of linear alkyl ammonium cations on film morphology, crystallinity, and charge transport in 2D tin halide perovskites is investigated. The carbon chain lengths of the organic spacers vary from propylammonium to heptanammonium. The increase of alkyl chain length leads to enhanced local charge carrier transport in the perovskite film with mobilities of up to 8 cm2 V-1 s-1, as confirmed by optical-pump terahertz spectroscopy. A similar improved macroscopic charge transport is also observed in FETs, only to the chain length of HA, due to the synergistic enhancement of film morphology and molecular organization. While the mobility increases with the temperature rise from 100 K to 200 K due to the thermally activated transport mechanism, the device performance decreases in the temperature range of 200 K to 295 K because of ion migration. These results provide guidelines on rational design principles of organic spacer cations for 2D tin halide perovskites and contribute to other optoelectronic applications.

Alkyl chain length influence of the functionalized diethanolamine ligand on the slow relaxation of the magnetization in {CoIII3DyIII3} complexes.

We report the synthesis, structural characterization and magnetic properties of a series of Co(III)/Dy(III) complexes built up from an N-alkyl derivatized amino-alcohol ligand diethanolamine, functionalized with CnH2n+1 alkyl chains (n = 3, 4, 6, 8 and 10). While n = 3 afforded a butterfly {CoIII2DyIII2} core, the other alkyl chains (n = 4, 6, 8) afforded hexanuclear triangle-in-triangle {CoIII3DyIII3} complexes as shown by single-crystal X-ray determinations. Infrared spectroscopy allows us to characterize the C10 derivative complex, which did not crystallize. Magnetic ac susceptibility data collected below 10 K at driving frequencies up to 10 kHz under zero-dc field and up to 1 T provide insight into the SMM behaviour of the studied complexes. The characteristic time of the magnetization dynamics can be understood in terms of the competing Raman, Direct and Orbach-like mechanisms. A relationship between the magnetization dynamics within the family of complexes and the increasing alkyl chain length is discussed.

Influence of carbon side chain length on the in vivo pharmacokinetic and pharmacodynamic characteristics of illicitly manufactured fentanyls.

Since 2016, illicitly manufactured fentanyls and fentanyl analogs (referred to as IMFs) have contributed to an increase in drug overdoses. Although fentanyl has been characterized and evaluated extensively in animals and humans, many of the clandestinely synthesized analogs of fentanyl have not and users may unknowingly ingest these IMFs leading to overdose and potentially death. The pharmacodynamic (PD) and pharmacokinetic (PK) properties of four IMFs and fentanyl were evaluated in Sprague-Dawley rats. A 300-μg/kg subcutaneous dose of each compound (fentanyl, acetylfentanyl, cyclopropylfentanyl, butyrylfentanyl, and valerylfentanyl) was given. PD parameters were measured using a tail flick meter and core body temperature. Blood was drawn to evaluate PK parameters utilizing liquid chromatography tandem mass spectrometry (LC-MS/MS). Fentanyl displayed the greatest and longest lasting analgesia with a tail flick response of 10s (the maximum cutoff). Additionally, fentanyl produced an average -4.9°C in core body temperature resulting in the greatest decrease in core body temperature. Acetylfentanyl, with the shortest carbon side chain, displayed the shortest T½, and lowest AUC and Cmax and resulted in an increase in body temperature. There were no other PK differences among the IMFs assessed. As IMFs are commonly seen on the streets and can pose significant risks to users (although these risks do depend on other factors such as dose and route of administration), there is a benefit to having the pharmacological properties of these compounds characterized to better understand the potential harm to humans.

Tetrahydropyridinylidene ammonium salts with arylalkyl and diarylalkyl substitution and their antiprotozoal activity

Tetrahydropyridin-4-ylidene salts with benzyl and dibenzyl substitution showed good antiprotozoal activity. This paper reports the synthesis of analogues with longer side chains. They were investigated for their antiprotozoal activities as well as for their cytotoxicity using microplate assays. The most active compounds showed activity against Trypanosoma brucei rhodesiense in concentrations < 0.06 µM. A series of compounds was active against Plasmodium falciparum NF54 in low nanomolar concentration and exhibited outstanding selectivity. The influence of substitution pattern and chain length on the antiprotozoal potencies were analyzed and structure–activity relationships were given. New compounds were characterized by FT-IR, HRMS, and NMR spectroscopy.Graphical abstract

Diselenophene-Dithioalkylthiophene Based Quinoidal Small Molecules for Ambipolar Organic Field Effect Transistors.

This work presents a series of novel quinoidal organic semiconductors based on diselenophene-dithioalkylthiophene (DSpDST) conjugated cores with various side-chain lengths (-thiohexyl, -thiodecyl, and -thiotetradecyl, designated DSpDSTQ-6, DSpDSTQ-10, and DSpDSTQ-14, respectively). The purpose of this research is to develop solution-processable organic semiconductors using dicyanomethylene end-capped organic small molecules for organic field effect transistors (OFETs) application. The physical, electrochemical, and electrical properties of these new DSpDSTQs are systematically studied, along with their performance in OFETs and thin film morphologies. Additionally, the molecular structures of DSpDSTQ are determined through density functional theory (DFT) calculations and single-crystal X-ray diffraction analysis. The results reveal the presence of intramolecular S (alkyl)···Se (selenophene) interactions, which result in a planar SR-containing DSpDSTQ core, thereby promoting extended π-orbital interactions and efficient charge transport in the OFETs. Moreover, the influence of thioalkyl side chain length on surface morphologies and microstructures is investigated. Remarkably, the compound with the shortest thioalkyl chain, DSpDSTQ-6, demonstrates ambipolar carrier transport with the highest electron and hole mobilities of 0.334 and 0.463 cm2 V-1 s-1 , respectively. These findings highlight the excellence of ambipolar characteristics of solution-processable OFETs based on DSpDSTQs even under ambient conditions.

Fabrication of Schiff-base crosslinked films modified dialdehyde starch with excellent UV-blocking and antibacterial properties for fruit preservation

Starch-based films have received considerable attention, owing to their commendable biocompatible and biodegradable properties; however, their poor ultraviolet (UV)-blocking and antibacterial performances limit their application in fruit preservation. Herein, bio-based bifunctional benzoxazine (Bi-BOZ) compounds with different carbon chain lengths were synthesized, and the influence of chain lengths on the antibacterial effect was explored. Benzoxazine with 1,12-dodecanediamine as the amine source (BOZ-DDA) exhibited excellent antibacterial and antibiofilm activities, with minimum inhibitory concentrations of 21.7 ± 2.2 and 23.3 ± 2.6 μg/mL against Escherichia coli and Staphylococcus aureus, respectively, mainly because the electrostatic attraction and hydrophobic effect of BOZ-DDA, effectively disrupted the bacterial integrity. DS/DDA films with hydrophobic, antibacterial, and UV-resistant abilities were prepared by the Schiff-base reaction between BOZ-DDA and dialdehyde starch (DS). The interactions between the films increased with BOZ-DDA content, enhanced mechanical and barrier properties. DS/DDA films exhibited acid-responsive antibacterial activity attributed to the acid hydrolysis of Schiff bases, released of BOZ-DDA from the films, and the protonation of BOZ-DDA. DS/DDA films exhibited commendable antibacterial and anti-ultraviolet characteristics compared to commercially available films, allowing them to prevent the degradation of mangoes and grapes. As sustainable antibacterial materials, the multifunctional DS/DDA films manifest promising prospects in fruit preservation packaging applications.

The Influence of PEG Chain Length on the in vivo Tumor Accumulation of Self-assembled Amphiphilic Drug-PEG Polymeric Micelles

The integration of a drug and polyethylene glycol (PEG) into an amphiphilic polymer to form self-assembled micelles with high drug loading for self-delivery to tumors is recently reported, which has showed high clinical availability. However, the effect of PEG chain length on cell internalization efficiency and tumor targeting efficiency in this PEG-drug conjugate micelle self-delivery system has yet to be studied. Herein, pyropheophorbide-a (PhA) was used as a model drug and a fluorescent tracer to synthesize amphiphilic polymers with varying PEG chain lengths, which self-assembled into PhA-PEG2000 NPs and PhA-PEG5000 NPs with high drug loading (21.2% and 9.7%, respectively, according to calculation). The results showed that PhA-PEG2000 NPs had higher cell internalization in vitro than PhA-PEG5000 NPs, but much lower tumor accumulation in vivo than PhA-PEG5000 NPs. This was attributed to the longer in vivo blood circulation time of the latter. Furthermore, the in vitro and in vivo examinations revealed negligible side effects, indicating the intrinsic safety of the micelles. This study provides insight into the influence of PEG chain length on biodistribution of organs and tumor accumulation after intravenous administration of PEG-drug conjugate micelle and guides the design of drug incorporated amphiphilic polymer-based micelles.

Protein Adsorption on Mixed Self-Assembled Monolayers: Influence of Chain Length and Terminal Group.

Mixed self-assembled monolayers (SAMs) are often used as highly tunable substrates for biomedical and biosensing applications. It is well documented, however, that mixed SAMs can be highly disordered at the molecular level and do not pack as closely or homogeneously as single-component SAMs, particularly when the chain lengths and head groups of the SAM thiol components are significantly different. In this study, we explore the impact of SAM structure and mixing ratio (-OH and -CH3 termini) on the weak physisorption behavior of bovine serum albumin (BSA), which adsorbs more readily to hydrophobic, methyl-terminated SAMs. Our results suggest that once the mixture includes 50% or more of the methyl terminus, the mixing ratio alone is a relatively good predictor of adsorption, regardless of the relative chain lengths of the thiols used in the mixture. This trend persists at any mixing ratio for SAMs where methyl- and hydroxyl-terminated groups are the same length or where the hydroxyl-terminated thiol is longer. The only variance observed is at low mixing ratios (<50% methyl-terminated) for a mixed SAM where the methyl-terminated component has a longer chain length. Relative protein adsorption increases on these mixtures, perhaps due to the disordered exposure of the excess alkane backbone. Taken together, however, we do not find significant evidence that varying chain lengths for mixed SAMs prepared on polycrystalline substrates and analyzed in air have an outsized influence on nanoscopic adsorption behavior, despite molecular-level disorder in the SAM itself.

Correlation between absorbed acetylene spectral characteristic and nature of ionic liquids studied by in situ ATR-FTIR spectroscopy

Ionic liquids (ILs) are believed to be a prospective replacement for molecular solvents and are suggested to be used for storing and/or purifying acetylene. Systematic studies of the nature of the interaction between acetylene and different ILs may be necessary to predict new types of ionic liquids. Therefore, in order to investigate the absorption of acetylene by ionic liquids, in situ ATR-FTIR spectroscopy has been applied for the first time. Two series of ILs, such as [C2‍–‍10MIM][BF4] and ILs based on imidazolium with various anions, have been considered. A detailed analysis of the spectra of absorbed acetylene is given, with special attention being paid to the basicity of IL anions as well as the influence of the cation alkyl chain length. It has been found that the magnitude of the band shift associated with the CH stretching vibration and the antisymmetric CH bending vibration of absorbed acetylene correlates well with the change in the Kamlet-Taft β parameter of the ILs. Moreover, neither the free volume nor the IL polarity plays a key role in acetylene solubility. In addition, the enthalpy and entropy of absorption have been calculated for several ILs.

Molecular mechanism of influence of alkyl chain length in ionic surfactant on the wettability of low rank coal

Molecular mechanism of influence of alkyl chain length in ionic surfactant on the wettability of low rank coal

Investigating C3 and C4 esters and alcohols in a diesel engine: Combined influence of carbon chain length, oxyfuel type, and oxygen content

Diesel engines fueled by liquid fuels will continue to dominate the transportation and heavy machinery application market despite the advancement of other technologies. Studies have yet to be conducted to investigate the combined influence of carbon chain length, oxyfuel type, oxygen content, and blending ratio of esters and alcohols as additives in diesel fuel. The present study addresses this by preparing two sets of experiments using three-carbon (C3) and four-carbon (C4) additives, one at an equal blending ratio of 4% and the other at an equal oxygen mass content of 1.94%. Although the additives caused up to 24.84% rise in brake specific fuel consumption at low load, the value diminished to 7.86% at medium load and 11.63% at high load. The C4 fuels were found to have better NOx reduction potential than the C3 fuels. However, most additives significantly increased CO emissions, except for EE4.9 (4.9% ethyl ethanoate and 95.1% diesel), leading to 3.7% and 7.1% lower CO emissions than neat diesel at low and medium loads, respectively. Smoke emissions were also reduced by up to 32.84% when oxygenated additives were used. Although all blends tested are promising fuel alternatives in a diesel engine, EE4.9 provided the most suitable trade-off between engine performance and emissions.

Structure, aggregation dynamics and crystallization of superfolder green fluorescent protein: Effect of long alkyl chain imidazolium ionic liquids

Green fluorescent protein (GFP) and its variants are widely used in medical and biological research, especially acting as indicators of protein structural integrity, protein-protein interactions and as biosensors. This study employs superfolder GFP (sfGFP) to investigate the impact of varying alkyl chain length of 1-Cn-3-methylimidazolium chloride ionic liquid (IL) series ([Cnmim]Cl, n = 2, 4, 6, 8, 10, 12) on the protein fluorescence, structure, hydration, aggregation dynamics and crystallization behaviour. The results revealed a concentration-dependent decrease in the sfGFP chromophore fluorescence, particularly in long alkyl chain ILs ([C10mim]Cl and [C12mim]Cl). Tryptophan (Trp) fluorescence showed the quenching rate increased with longer alkyl chains indicating a nonpolar interaction between Trp57 and the alkyl chain. Secondary structural changes were observed at the high IL concentration of 1.5 M in [C10mim]Cl and [C12mim]Cl. Small-angle X-ray scattering (SAXS) indicated relatively stable protein sizes, but with IL aggregates present in [C10mim]Cl and [C12mim]Cl solutions. Dynamic light scattering (DLS) data showed increased protein size and aggregation with longer alkyl chain ILs. Notably, ILs and salts, excluding [C2mim]Cl, promoted sfGFP crystallization. This study emphasizes the influence of the cation alkyl chain length and concentration on protein stability and aggregation, providing insights into utilizing IL solvents for protein stabilization and crystallization purposes.

Influences of alcohols, urea and polyethylene glycol on the cloudy formation nature and physico-chemical parameters of the mixture of triton X-100 and ceftriaxone sodium salt

The phase separation of a nonionic surfactant (SFT), Triton X-100 (TX-100) and ceftriaxone sodium trihydrate (CTS) drug mixture was examined in the appearance of several alcohols (ethanol, 1-propanol, 2-propanol, 2-butanol) and hydrotropes (HDTs) (urea and polyethylene glycol (PEG)). The influences of changing composition and chain length of alcohols on the cloud points of aqueous TX-100 + CTS mixture were also assessed. The detected CP values were found to undergo an upsurge with the increased concentration of alcohols and HDTs. The computed ∆Gc0 values are acquired be positive in nature, demonstrating that the clouding of employed system was non-spontaneous in origin and the positive ∆Gc0 values were reduced with the growth of the contents of alcohols/HDTs. The obtained values of enthalpy (∆Hc0) and entropy (∆Sc0) were positive in magnitudes for most of the employed solvents with a few exceptions. The values of ∆Hc0 and ∆Sc0 were achieved as negative at lower contents of 2-butanol and highest content of urea/PEG. The enthalpy-entropy compensation variables (∆Hc0,*and Tc) associated with the clouding process of TX-100 + CTS mixture in aq. additive solutions were also calculated and interpreted in detailed way.