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Introduction: Topical antifungals for toenail onychomycosis must penetrate the nail to deliver an inhibitory concentration of free drug to the site of infection. In two ex vivo experiments, we tested the ability of topical antifungals to inhibit growth of Trichophyton rubrum and Trichophyton mentagrophytes, the most common causative fungi in toenail onychomycosis. Methods: Seven topical antifungals were tested: three U.S. Food and Drug Administration-approved products indicated for onychomycosis (ciclopirox 8% lacquer; efinaconazole 10% solution; tavaborole 5% solution) and four over-the-counter (OTC) products for fungal infections (tolnaftate 1% and/or undecylenic acid 25% solutions). The ability to inhibit fungal growth was tested in the presence and absence of keratin. Products were applied either to human cadaverous nails or keratin-free cellulose disks prior to placement on an agar plate (radius: 85 mm) seeded with a clinical isolate of T. rubrum or T. mentagrophytes. After incubation, the zone of inhibition (ZI), defined as the radius of the area of no fungal growth, was recorded. Results: In the nail penetration assay, average ZIs for efinaconazole (T. rubrum: 82.1 mm; T. mentagrophytes: 63.8 mm) were significantly greater than those for tavaborole (63.5 mm; 39.1 mm), ciclopirox (7.4 mm; 3.6 mm) and all OTC products (range: 10.5–34.2 mm against both species; all P < 0.001). In the cellulose disk diffusion assay, efinaconazole and tavaborole demonstrated maximal antifungal activity against both species (ZIs = 85 mm); average ZIs against T. rubrum and T. mentagrophytes were smaller for ciclopirox (59.0 and 55.7 mm, respectively) and OTC products (range: 31.2–57.8 mm and 25.7–47.7 mm, respectively). Conclusions: Among all antifungals tested, the ability to penetrate human toenails to inhibit growth of both T. rubrum and T. mentagrophytes was greatest for efinaconazole, followed by tavaborole. These results indicate superior transungual penetration of efinaconazole compared to the other antifungals, suggesting lower keratin binding in the nail. [ABSTRACT FROM AUTHOR]

The control of Candida albicans biofilm formation on dentures made of poly(methyl methacrylate) (PMMA) is an important challenge due to the high resistance to antifungal drugs. Interestingly, the natural compounds undecylenic acid (UDA) and farnesol (FAR) both prevent C. albicans biofilm formation and could have a synergetic effect. We therefore modified PMMA with a combination of UDA and FAR (UDA+FAR), aiming to obtain the antifungal PMMA_UDA+FAR composites. Equal concentrations of FAR and UDA were added to PMMA to reach 3%, 6%, and 9% in total of both compounds in composites. The physico-chemical properties of the composites were characterized by Fourier-transform infrared spectroscopy and water contact angle measurement. The antifungal activity of the composites was tested on both biofilm and planktonic cells with an XTT test 0 and 6 days after the composites' preparation. The effect of the UDA+FAR combination on C. albicans filamentation was studied in agar containing 0.0125% and 0.4% UDA+FAR after 24 h and 48 h of incubation. The results showed the presence of UDA and FAR on the composite and decreases in the water contact angle and metabolic activity of both the biofilm and planktonic cells at both time points at non-toxic UDA+FAR concentrations. Thus, the modification of PMMA with a combination of UDA+FAR reduces C. albicans biofilm formation on dentures and could be a promising anti-Candida strategy. [ABSTRACT FROM AUTHOR]

This study reports a sustainable strategy to produce polymeric materials with convenient properties, employing principles close to green chemistry, starting from epoxy/methacrylate vegetable oil monomers. New bio‐based derivatives were obtained from the well‐known epoxidized linseed oil, reacted with a renewable reagent, undecylenic acid, using suitable synthesis parameters in heterogeneous catalysis. The undecylenic double bonds grafted on the linseed oil structure were then reacted, resulting epoxidized undecylenic acid‐linseed oil (monomer 1). Monomer 1 was further used as an intermediate to obtain methacrylic derivatives: monomer 2—methacrylate epoxidized undecylenic acid‐linseed oil (bearing both epoxy and methacrylic moieties) and monomer 3—methacrylate undecylenic acid‐linseed oil (bearing only methacrylic functionalities). These three monomers were employed in different eco‐friendly ultraviolet/visible light curing attempts, proving their ability to generate polymer networks in different reaction conditions. The resulting materials were investigated through different thermal and thermo‐mechanical assays, establishing their general properties. The influence of the undecylenic fragments, epoxy/methacrylate content and curing conditions were established. Gel fraction varied according to the initial precursor composition (62/87% for the epoxy‐based materials; 58/91% for the methacrylic‐based materials). A good elasticity was observed for the new materials (Tg ranging from 20 to 44°C), and a great thermal resistance also (thermal degradation temperatures of 400/453°C for the epoxy network and 382°C for the methacrylic one), in good agreement with other studied mono‐ or di‐functional polymer matrices. [ABSTRACT FROM AUTHOR]

Membrane materials with osmium nanoparticles have been recently reported for bulk membranes and supported composite membrane systems. In the present paper, a catalytic material based on osmium dispersed in n–decanol (nD) or n–dodecanol (nDD) is presented, which also works as an emulsion membrane. The hydrogenation of p–nitrophenol (PNP) is carried out in a reaction and separation column in which an emulsion in the acid-receiving phase is dispersed in an osmium nanodispersion in n–alcohols. The variables of the PNP conversion process and p–aminophenol (PAP) transport are as follows: the nature of the membrane alcohol, the flow regime, the pH difference between the source and receiving phases and the number of operating cycles. The conversion results are in all cases better for nD than nDD. The counter-current flow regime is superior to the co-current flow. Increasing the pH difference between the source and receiving phases amplifies the process. The number of operating cycles is limited to five, after which the regeneration of the membrane dispersion is required. The apparent catalytic rate constant (kapp) of the new catalytic material based on the emulsion membrane with the nanodispersion of osmium nanoparticles (0.1 × 10−3 s−1 for n–dodecanol and 0.9 × 10−3 s−1 for n–decanol) is lower by an order of magnitude compared to those based on adsorption on catalysts from the platinum metal group. The advantage of the tested membrane catalytic material is that it extracts p–aminophenol in the acid-receiving phase. [ABSTRACT FROM AUTHOR]

Undecylenic acid, glycerol, and CO2 were used as building blocks for obtaining a fully bio‐based carbonated monomer, useful for polyurethanes. The functionality of the monomer was close to 3 cyclic carbonates/mol, located in terminal positions. In a first stage, a synthetic triglyceride was obtained with 99% selectivity by esterification of glycerol and undecylenic acid at 160°C. The triglyceride was then epoxidized using H2O2 and Amberlyst 15 or Amberlite IR‐120 acidic exchange resins at 57°C. The selectivity to epoxide was kept constant at 98% using Amberlite IR‐120. Terminal cyclic carbonates were then inserted through epoxide moieties under mild conditions by the chemical fixation of CO2 at 80°C and 6 MPa in 6 h. A complete conversion was obtained in 6 h reaction while the selectivity to carbonate groups was near to 99% during all the reaction time. An elastomeric polyhydroxyurethane was obtained by aminolysis of the carbonated monomer with ethylenediamine at 70°C, affording a Young's modulus of 22.6 MPa and Tg of −15.2°C. The material showed a good thermal stability below 240°C. [ABSTRACT FROM AUTHOR]

Evaluation of undecylenic acid (UA) and its tertiary amide N,N-dibutylundecenamide (DBUA) activity­ in vitro against the standard and antibiotic-resistant Escherichia coli and Staphylococcus aureus strains was carried out. The antibacterial potential of the acid and its amide at 2.5 and 5.0 μM concentration both against gram-positive bacteria (S. aureus) and gram-negative (E. coli) cultures was confirmed by monitoring the diameter of the bacterial growth inhibition zones. The docking study identified methionine aminopeptidase (MAP) as the most energy-favorable potential biotarget associated with the drug resistance of E. coli and S. aureus with a binding energy in the range from -8.0 to -8.5 kcal/mol. The ligands complexation was due to the formation of hydrogen bonds with ASP108, HIS171, HIS178, GLU204, GLU235, HIS76, ASP104, GLU233, ASP93 and metal-acceptor interactions with Co2+. Overall, the results indicated that UA and DBUA activity against antibiotic-resistant strains creates prospects for the development of new antibacterial formulations.

This work evaluated the process for heptaldehyde, undecylenic acid, and methyl undecenoate production from castor oil, methyl ester of castor oil, and ricinoleic acid. Experiments were performed in a continuous pilot-plant scale pyrolysis reactor. Those are very important green chemical products that the thermal cracking of castor oil might produce. Transesterification of castor oil produces methyl ricinoleate, and its thermal cracking generates methyl undecenoate and heptaldehyde. The pyrolysis temperatures tested were 530 °C, 545 °C, 560 °C, and 575 °C, with residence time from 17 s to 32 s and mass flow at 400 g/h of the mixture of materials with 25% distilled water. It was observed that the temperature influenced the bio-oil yield in different degree for each material. The bio-oil was characterized by iodine index, acid number, and mass, and the contents of its compounds were obtained by GC-FID chromatography. The best result for the undecylenic acid mass yield of the desired compounds occurred at 530 °C, achieving 17.8% from ricinoleic acid and 16.5% from castor oil. For the heptaldehyde, the highest production was also obtained at 530 °C, with a value of 20.7% from methyl ester and 15.2% from ricinoleic acid. [ABSTRACT FROM AUTHOR]

Bio‐based polyols derived from vegetable oils generally contain the dangling chains, which have recently attracted significant attention due to their influence on the preparation and performance of the waterborne polyurethane. Herein, a novel undecylenic‐based primary glycol (UPG) without dangling chains synthesized and the oleic‐based primary glycol (OPG) with dangling chains reported by our previous work were used to prepare straight‐chain and dangling‐chain bio‐based waterborne polyurethane (BWPU), respectively, to study the difference between the two diols and the effects of dangling chains on the synthesis and performance of BWPU. First, the UPG without dangling chains displayed higher activation energy (Ea/Eo = 77.72/80.56 kJ mol−1) and longer reaction end point of prepolymer (240 min), indicating relatively lower reactivity to isocyanate. In addition, the dangling chains were found to influence the dispersion stability of BWPU, and the minimum dosage of DMPA for maintaining dispersion stability was 6.5 wt% for OPG but 5.5 wt% for UPG. The average particle size of BWPU is greater for OPG than for UPG with the same DMPA content. Finally, performance studies revealed that dangling‐chain BWPU showed higher hydrophobicity, extensibility, and low temperature resistance, but lower thermal stability (Td5%) and tensile strength. This work comprehensively clarified the effects of linear and branched bio‐based polyols on the synthesis and properties of BWPU, and provided guidance for the development and application of bio‐based polyols and BWPU coatings. [ABSTRACT FROM AUTHOR]

Castor oil is one important raw material that could serve as a renewable feedstock for industries in the age of exhausting fossil fuels. The chemical composition of oil and the structure of hydroxyl fatty acid are responsible for its unique physicochemical properties. The oil has diverse applications from pharmaceuticals to polyamides, from the manufacturing of ski boots to durable frames, and from lubricants to laxatives. The present review gives an insight into the physicochemical properties of castor oil and its application. The oil is used for the production of a great variety of its derivatives. Out of many derivatives of castor oil, four are produced and utilized at a larger scale. The names of the four derivates are ricinoleic acid, sebacic acid, undecylenic acid, and γ‐decalactone. The review will aim toward an insight into the evolved techniques for the manufacturing of these derivatives of castor oil, the biotechnological route of production, and metabolic engineering approaches. Though the industrial significance of castor oil and its derivatives had been known for ages, methods for their production are continuously changing. [ABSTRACT FROM AUTHOR]

Undecylenic acid, a monounsaturated fatty acid, is currently in clinical use as a topical antifungal agent, however the potential for therapeutic application in other disease settings has not been investigated. In this study, we describe a novel platform for the solubilization of fatty acids using amino acids and utilize this approach to define a tumoricidal activity and underlying mechanism for undecylenic acid. We examined a novel formulation of undecylenic acid compounded with L-Arginine, called GS-1, that induced concentration-dependent tumor cell death, with undecylenic acid being the cytotoxic component. Further investigation revealed that GS-1-mediated cell death was caspase-dependent with a reduction in mitochondrial membrane potential, suggesting a pro-apoptotic mechanism of action. Additionally, GS-1 was found to localize intracellularly to lipid droplets. In contrast to previous studies where lipid droplets have been shown to be protective against fatty acid-induced cell death, we showed that lipid droplets could not protect against GS-1-induced cytotoxicity. We also found a role for Fatty Acid Transport Protein 2 (FATP2) in the uptake of this compound. Collectively, this study demonstrates that GS-1 has effective pro-apoptotic antitumor activity in vitro and, together with the novel platform of fatty acid solubilization, contributes to the re-emerging field of fatty acids as potential anti-cancer therapeutics. [ABSTRACT FROM AUTHOR]

Mineral-based lubricants are being supplanted by bio-based lubricants because of environmental concerns and the depletion of fossil resources. The derivatives of edible and non-edible oils are considered potential alternatives to existing natural mineral oil base stocks in certain lubricant applications, where immediate intraction with the environment is predicted. A new class of epoxides were synthesized from the undecylenic esters of 2-ethyl hexanol, neopentyl glycol (NPG), and trimethylolpropane (TMP). These unsaturated esters were epoxidized by using meta chloro perbenzoic acid. The synthesized epoxides were characterized by spectral studies (¹HNMR, 13CNMR, IR) physio-chemical (density, specific gravity) and lubricant properties (kinematic viscosity, viscosity index, flash point, fire point, cloud point, pour point, copper strip corrosion). TMP epoxide has a high viscosity index, high flash point, and low pour point compared to 2-ethyl hexyl epoxide and NPG epoxide. [ABSTRACT FROM AUTHOR]

The photoluminescence (PL) response of porous Si has potential applications in a number of sensor and bioimaging techniques. However, many questions still remain regarding how to stabilize and enhance the PL signal, as well as how PL responds to environmental factors. Regenerative electroless etching (ReEtching) was used to produce photoluminescent porous Si directly from Si powder. As etched, the material was H-terminated. The intensity and peak wavelength were greatly affected by the rinsing protocol employed. The highest intensity and bluest PL were obtained when dilute HCl(aq) rinsing was followed by pentane wetting and vacuum oven drying. Roughly half of the hydrogen coverage was replaced with –RCOOH groups by thermal hydrosilylation. Hydrosilylated porous Si exhibited greater stability in aqueous solutions than H-terminated porous Si. Pickling of hydrosilylated porous Si in phosphate buffer was used to increase the PL intensity without significantly shifting the PL wavelength. PL intensity, wavelength and peak shape responded linearly with temperature change in a manner that was specific to the surface termination, which could facilitate the use of these parameters in a differential sensor scheme that exploits the inherent inhomogeneities of porous Si PL response.

The synthesis of undecylenic acid partial esters can be performed at mild temperature with a classical esterification reaction catalyzed by dodecylbenzene sulfonic acid (DBSA). A semi‐empirical molecular modeling on the different reaction intermediates indicates that DBSA can strongly decrease their heats of formation through hydrogen bonding. Diester formation seems to be thermodynamically favored with a selectivity for alpha, alpha, or alpha, beta forms that depend on the geometry of the catalyst‐intermediate configuration. Triesters are not favored but a high selectivity for monoesters requires a kinetic control. Experimental approach, considering different DBSA concentrations and temperature partially confirms the theoretical predictions but surfactant properties of DBSA and monoesters may induce nonpredicted geometries. Global apparent activation energies are calculated, corresponding to the formation and hydrolysis of mono and diesters. If water trapping allows the decrease of hydrolysis reaction constants, the presence of water and subsequent phase separation may explain differences between theoretical and experimental results and could help increasing monoester selectivity. [ABSTRACT FROM AUTHOR]

Protocellular membranes are thought to be composed of mixtures of single chain amphiphiles, such as fatty acids and their derivatives, moieties that would have been part of the complex prebiotic chemical landscape. The composition and physico-chemical properties of these prebiological membranes would have been significantly affected and regulated by their environment. In this study, pertinent properties were systematically characterized, under early Earth conditions. Two different fatty acids were mixed with their respective alcohol and/or glycerol monoester derivatives to generate combinations of binary and tertiary membrane systems. Their properties were then evaluated as a function of multiple factors including their stability under varying pH, varying Mg2+ ion concentrations, dilution regimes, and their permeability to calcein. Our results demonstrate how environmental constraints would have acted as important prebiotic selection pressures to shape the evolution of prebiological membranes. The study also illustrates that compositionally diverse membrane systems are more stable and robust to multiple selection pressures, thereby making them more suitable for supporting protocellular life. [ABSTRACT FROM AUTHOR]

Onychomycosis is a prominent fungal infection that causes discoloration, thickening, and mutilation leading to the separation of the nail from the nail bed. Treatment modalities for onychomycosis may include oral, topical, or combination therapy with antifungals and at times may require chemical or surgical intervention. The burden of side effects of antifungals is enormous, and therefore using molecular docking-based drug selection in context with the target keratin protein would ensure better disease management. Ciclopirox, Amorolfine HCl, Efinaconazole, Tioconazole, and Tavaborole were submitted for assessment, revealing that Amorolfine HCl is the best fit. Consequently, two formulations (Nail lacquer and nanoemulgel) were developed from Amorolfine HCl to validate the in silico screening outcomes. The formulations were further fortified with over-the-counter ingredients vis-a-vis with vitamin E in nail lacquer and undecylenic acid in nanoemulgel for their prominent roles in improving nail health. Both the formulations were systematically designed, optimized, and characterized. Amorolfine HCl containing nanoemulgel (NEG) was developed using undecylenic acid as an oil phase and thioglycolic acid as a penetration enhancer. The quality parameters evaluated were particle size, the zeta potential for nanoemulsion (NE) (78.04 ± 4.724 nm and −0.7mV, respectively), in vitro cumulative drug release (96.74% for NE and 88.54% for NEG), and transungual permeation (about 73.49% for NEG and 54.81% for NE). Nail lacquer was evaluated for the drying time, non-volatile content, and blush test. In vitro cumulative drug release of the developed nail lacquer and comparator marketed formulations were around 81.5% and 75%, respectively. Similarly, the transungual drug permeation was 6.32 μg/cm2 and 5.89 μg/cm2, respectively, in 24 h. The in silico guided preparation of both formulations containing Amorolfine HCl and over the counter ingredients is amenable for therapeutic use against onychomycosis and will be evaluated in the in vivo model.

Porous silicon nanoparticles (PSiNPs) are non-toxic photoluminescence imaging agents whose potential for biophotonic applications has been widely reported in recent years. However, this material suffers from intrinsic limitations, due to its chemical instability and rapid photoluminescence extinction on exposure to the physiological environment. In this letter, a mild functionalization procedure for PSiNP stabilization, based on undecylenic acid conjugation via hydrosilylation, is proven to be effective under simulated biological conditions [phosphate-buffered saline (PBS) 0.1 M, pH = 7.4]. Once stored in isopropanol, bare and hydrosilylated PSiNPs (h·PSiNPs) show similar photoemissive properties: photoluminescence quantum yield (>10%), steady-state spectra, and emission lifetime. Interestingly, the behaviour of these nanoparticles is completely different in the physiological medium: the morphology and the photoluminescence emission of bare PSiNPs completely degrade within 2 h, whereas a full preservation of the same features up to 6 h is demonstrated for h·PSiNPs. [ABSTRACT FROM AUTHOR]

A simple synthetic route is used for the preparation of hydroxyl functionalized polyesters from an AB-type monomer carrying an epoxy and carboxylic acid group. A systematic study of the reaction conditions suggested that tetrabutylphosphonium bromide was the better polymerization catalyst to obtain the highest conversion of linear polymers with moderate molecular weights. Enzymatic catalyst (CALB), in contrast, yielded branched polymers with polyether units. The synthesized polymers were structurally characterized in detail, using model compounds previously synthesized, by 1 H, 13 C, and 19 F NMR. Polyesters were characterized by FTIR, SEC, DSC and TGA too. The post-polymerization modification of the reactive hydroxyl sites present along the polymer backbone with N-Boc protected l -phenylalanine and l -serine was essayed to test the ability of these polyesters to prepare polymer bioconjugates. [ABSTRACT FROM AUTHOR]

Due to the growing issues with fungal infections, especially with Candida, there is still a need to develop novel anti-Candida materials. One of the known antifungal agents is undecylenic acid (UA), which still cannot be efficiently used due to its oily nature, and thus limited solubility. By taking advantage of the properties of UA, we developed an emulsion with hexagonal phase, i.e., hexosomes, whose structure and morphology was studied by small-angle X-ray scattering and cryo-electron microscopy, respectively. The presence of UA in the hexosome was confirmed by spectroscopy. Moreover, we studied the anti-Candida effect of hexosomes and their cytotoxicity toward human cells. The minimal inhibitory concentration for the 50% and 90% Candida-growth reduction was found at 0.01 and 0.16 wt % hexosomes, respectively (i.e., 2 and 32 pghex/C.a.cell, respectively). The percentage of metabolically active Candida was reduced by 72-96% at hexosome concentrations of 1.0-8.2 pghex/C.a.cell as compared to untreated Candida. Furthermore, at the same concentration range the embedded filamentation test after 24 and 48 h showed the inhibition of both the filamentation and growth of Candida, while the preliminary toxicity test showed that hexosomes were nontoxic for human cells. All these render the here-developed hexosomes with UA efficient and promising anti-Candida agents. [ABSTRACT FROM AUTHOR]

Undecylenic acid (UA), known as antifungal agent, still cannot be used to efficiently modify commercial dental materials in such a way that this affects Candida. Actually, issues with Candida infections and fungal resistance compromise the use of Poly(methyl-methacrylate) (PMMA) as dental material. The challenge remains to turn PMMA into an antifugal material, which can ideally affect both sessile (attached) and planktonic (free-floating) Candida cells. We aimed to tackle this challenge by designing PMMA-UA composites with different UA concentrations (3-12%). We studied their physico-chemical properties, the antifungal effect on Candida and the cytotoxicity toward human cells. We found that UA changes the PMMA surface into a more hydrophilic one. Mainly, as-preparation composites with ≥6% UA reduced sessile Candida for >90%. After six days, the composites were still efficiently reducing the sessile Candida cells (for ~70% for composites with ≥6% UA). Similar results were recorded for planktonic Candida. Moreover, the inhibition zone increased along with the UA concentration. The antifungal effect of UA was also examined at the surface of an UA-loaded agar and the minimal inhibitory concentration (MIC90) was below the lowest-studied 0.0125% UA. Furthermore, the embedded filamentation test after 24 h and 48 h showed complete inhibition of the Candida growth at 0.4% UA. [ABSTRACT FROM AUTHOR]

Enzymatic synthesis of glyceryl monoundecylenate (GMU) was performed using indigenously immobilizedCandida anatarcticalipase B preparation (named as PyCal) using glycerol and undecylenic acid as substrates. The effect of molar ratio, enzyme load, reaction time, and organic solvent on the reaction conversion was determined. Both batch and continuous processes for GMU synthesis with shortened reaction time were developed. Under optimized batch reaction conditions such as 1:5 molar ratio of undecylenic acid and glycerol, 2 h of reaction time at 30% substrate concentration intert-butyl alcohol, conversion of 82% in the absence of molecular sieve, and conversion of 93% in the presence of molecular sieve were achieved. Packed bed reactor studies resulted in high conversion of 86% in 10-min residence time. Characterization of formed GMU was performed by FTIR, MS/MS. Enzymatic process resulted in GMU as a predominant product in high yield and shorter reaction time periods with GMU content of 92% and DAG content of 8%. Optimized GMU synthesis in the present study can be used as a useful reference for industrial synthesis of fatty acid esters of glycerol by the enzymatic route. [ABSTRACT FROM AUTHOR]

The UV-curable hyperbranched urethane acrylate oligomers modified with different fatty acids including undecylenic acid (UCA), myristic acid (MA), and oleic oil (OA) are successfully synthesized in this paper. The prepared oligomers are characterized using FTIR, HNMR, GPC, DSC, and TGA. The properties of the UV-curable films formed by these oligomers are also determined. The effects of the oligomer structures including double bond content, chain length of the modified fatty acids, and content of fatty acid and polyurethane acrylate segment, on the properties of the cured films, which are tack-free time, pencil hardness, impact resistance, adhesion, and boiling water resistance, are discussed in detail. It is observed that the curing film formed by HBPE-60%UCA-20%PUA shows the best comprehensive performance among the films prepared in this study. [ABSTRACT FROM AUTHOR]

The main goal of the presented research was to investigate the biocompatibility of polycaprolactone (PCL)-based nanoparticles and to evaluate the neuroprotective action of the encapsulated, water-insoluble neuroprotective substance − undecylenic acid (UDA). The neuroprotectant-loaded nanoparticles (NPs) were prepared from polymer containing toluene based nanoemulsions formed by the phase inversion composition (PIC) technique followed by solvent evaporation. Two types of PCL-based UDA-loaded nanoparticles were synthesized: PCL and PCL-PEG (using poly(ethylene glycol)-block-poly(ε−caprolactone) methyl ether). The average size of PCL/UDA NCs was around 120 nm and for PCL-PEG/UDA around 150 nm. The concentration of both types of NCs was similar: 2 × 10 10 particles ml −1 and the zeta potential of UDA-loaded PCL and PCL-PEG NCs −24 mV and −21 mV respectively. Biocompatibility of synthesized nanocarriers was evaluated in the SH-SY5Y human neuroblastoma cell line using cell viability/toxicity assays (MTT reduction, LDH release). The PCL and PCL-PEG nanocarriers at concentration 0.5 × 10 10 particles ml −1 did not show deleterious effects on human neuroblastoma cells line. The neuroprotection studies revealed that UDA loaded in PCL or PCL-PEG nanocarriers retained its neuroprotective potential against Staurosporine-evoked SH-SY5Y cell damage. [ABSTRACT FROM AUTHOR]

Carbonization of magnetic polymer microspheres is one of the methods for the preparation of magnetic carbon materials. Fe3O4magnetic particle characteristics considerably influence the magnetic content and size distribution of magnetic polymer microspheres. The characteristics of Fe3O4nanoparticles modified by oleic acid (OA) and undecylenic acid (UA) were analyzed by X-ray diffraction, Fourier transform infrared, scanning electron microscopy, dynamic laser light scattering, thermogravimetry/differential thermogravimetry, vibrating sample magnetometer, and water contact angle. Fe3O4nanoparticles modified by OA and UA are nearly spherical and exhibit superparamagnetism. Fe3O4particle size and saturation magnetization are slightly influenced by the OA and UA composition. OA and UA both are chemically adsorbed onto Fe3O4as bidentate chelates. OA shows easier adsorption onto Fe3O4than UA. OA groups have an expanded arrangement on OA@Fe3O4, whereas UA groups have a condensed arrangement on UA@Fe3O4. Particle lipophilicity decreases and particle clustering increases with decreasing OA content and increasing UA content on OA-UA@Fe3O4nanoparticles. [ABSTRACT FROM AUTHOR]

The self-assembling properties of glycerol esters in water are well known. Still, few data on glycerol monoesters of undecylenic acid are available. The aim of this study was to highlight the behavior of glycerol monoundecenoate (GM-C11:1) in different diluted and concentrated states. Its self-assembling properties in water and upon solid inorganic surfaces were investigated in the diluted state using surface tension experiments, atomic force microscopy, and cryogenic transmission electron microscopy studies. In the concentrated state, the gelling properties in the presence of water were investigated using polarized light microscopy, differential scanning calorimetry (DSC), and small-angle X-ray scattering (SAXS) experiments. GM-C11:1 at 100 mg/L self-assembles at the liquid/air interfaces as aggregates of approximately 20 nm in diameter, organized into concentric forms. These aggregates are spherical globules composed of several molecules of GM-C11:1. At higher concentrations (1000 and 104 mg/L), GM-C11:1 is able to uniformly coat liquid/air and liquid/solid interfaces. In bulk, GM-C11:1 forms spontaneously aggregates and vesicles. In a more concentrated state, GM-C11:1 assembles into lamellar Lβ and Lα forms in water. By cross-referencing SAXS and DSC findings, we were able to distinguish between interlamellar water molecules strongly bound to GM-C11:1 and other molecules remaining unbound and considered to be "mobile" water. The percentage of water strongly bound was proportional to the percentage of GM-C11:1 in the system. In this case, GM-C11:1 appears to be an effective molecule for surface treatments for which water retention is important. [ABSTRACT FROM AUTHOR]

A series of fuel borne catalysts (FBC) based on an iron oxide core stabilized by various long chain carboxylic acids were synthesized, characterized and tested in model soot combustion. As the capping agents methacrylic (C4), undecylenic (C11), oleic (C18) and erucic (C22) acids were used. The FBC precursors and the resultant catalysts were examined by Raman, FTIR, EPR, UV–vis and TEM/SAED techniques, whereas the catalytic reactivity in combustion of a model soot (Printex U) was evaluated by TG/DTA. For all the investigated FBC derived catalysts, it was found that the core of the catalyst consists of Fe 2 O 3 of a crystallite size in range of 5–8 nm, which is beneficial for the soot combustion activity. While a strong positive effect on the catalyst performance was observed for all the alkyl chain lengths, the best results were obtained for a hybrid FBC catalyst with two types (C11 and C18) of capping ligands. The effect of the chain length of the capping agent on the soot combustion process was discussed in terms of promotion of soot ignition by the more reactive C11 and combustion sustentation by heat transfer from the long chain C18 to soot particles, as implied by the observed overlapping of the combustion temperature windows of those moieties. For such hybrid catalysts, the ignition temperature of the soot combustion was lowered to almost 150 °C, and the total soot combustion accomplished below ∼470 °C. The high activity of the hybrid FBC catalysts makes them a promising alternative/backup for the particulate filter technology in light oil burners and related applications. [ABSTRACT FROM AUTHOR]

This paper investigates phase equilibria of interest for the hydroesterification of 10-undecenoic acid methyl ester with methanol and carbon monoxide to dodecanedioic acid dimethyl ester in a solvent system composed of methanol and n-dodecane. Carbon monoxide solubilities were measured in 10-undecenoic acid methyl ester, dodecanedioic acid dimethyl ester, and a mixture of methanol/dodecanedioic acid dimethyl ester at 363 and 393 K and at pressures up to 15 MPa. Vapor-liquid equilibrium measurements in the systems methanol/10-undecenoic acid methyl ester, methanol/dodecanedioic acid dimethyl ester, n-dodecane/10-undecenoic acid methyl ester, n-dodecane/dodecanedioic acid dimethyl ester, and 10-undecenoic acid methyl ester/dodecanedioic acid dimethyl ester were performed at temperatures between 342 and 437 K and at pressures of 2 or 80 kPa. The measured data were accurately modeled using the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT). [ABSTRACT FROM AUTHOR]

Chronic heart failure, predominantly developed after myocardial infarction, is a leading cause of high mortality worldwide. As existing therapies have still limited success, natural and/or synthetic nanomaterials are emerging alternatives for the therapy of heart diseases. Therefore, we aimed to functionalize undecylenic acid thermally hydrocarbonized porous silicon nanoparticles (NPs) with different targeting peptides to improve the NP's accumulation in different cardiac cells (primary cardiomyocytes, non-myocytes, and H9c2 cardiomyoblasts), additionally to investigate the behavior of the heart-targeted NPs in vivo . The toxicity profiles of the NPs evaluated in the three heart-type cells showed low toxicity at concentrations up to 50 μg/mL. Qualitative and quantitative cellular uptake revealed a significant increase in the accumulation of atrial natriuretic peptide (ANP)-modified NPs in primary cardiomyocytes, non-myocytes and H9c2 cells, and in hypoxic primary cardiomyocytes and non-myocytes. Competitive uptake studies in primary cardiomyocytes showed the internalization of ANP-modified NPs takes place via the guanylate cyclase-A receptor. When a myocardial infarction rat model was induced by isoprenaline and the peptide-modified [ 111 In]NPs administered intravenously, the targeting peptides, particularly peptide 2, improved the NPs' accumulation in the heart up to 3.0-fold, at 10 min. This study highlights the potential of these peptide-modified nanosystems for future applications in heart diseases. [ABSTRACT FROM AUTHOR]

Bacterial and fungal infections in the use of surgical devices and medical implants remain a major concern. Traditional bioadhesives fail to incorporate anti-microbial properties, necessitating additional anti-microbial drug injection. Herein, by the introduction of the clinically used and inexpensive anti-fungal agent, 10-undecylenic acid (UA), into our recently developed injectable citrate-based mussel-inspired bioadhesives (iCMBAs), a new family of anti-bacterial and anti-fungal iCMBAs (AbAf iCs) was developed. AbAf iCs not only showed strong wet tissue adhesion strength, but also exhibited excellent in vitro cyto-compatibility, fast degradation, and strong initial and considerable long-term anti-bacterial and anti-fungal ability. For the first time, the biocompatibility and anti-microbial ability of sodium metaperiodate (PI), an oxidant used as a cross-linking initiator in the AbAf iCs system, was also thoroughly investigated. Our results suggest that the PI-based bioadhesives showed better anti-microbial properties compared to the unstable silver-based bioadhesive materials. In conclusion, AbAf iCs family can serve as excellent anti-bacterial and anti-fungal bioadhesive candidates for tissue/wound closure, wound dressing, and bone regeneration, especially when bacterial or fungal infections are a major concern. [ABSTRACT FROM AUTHOR]

The solubilities of 10-undecenoic acid and geraniol in supercritical carbon dioxide were measured at 308, 313, 323 and 333 K, and at pressures of 10–18 MPa. Solubilities (in mole fraction) ranged from 0.4 × 10 −3 to 17.4 × 10 −3 for 10-undecenoic acid and 2.7 × 10 −3 to 25 × 10 −3 for geraniol, respectively. The AARD was around 11% and 5% for these models for 10-undecenoic acid and geraniol, respectively. The solubilities of both compounds showed retrograde behavior wherein the solubilities decrease with temperature at isobaric conditions. The solubility of geraniol was higher than 10-undecenoic acid at all investigated temperatures and pressures. The data were found to be self consistent based on the Mendez-Santiago model. New models based on association theory using van Laar and Margules activity coefficient models for solute in liquid phase were derived, and used to correlate the solubilities. [ABSTRACT FROM AUTHOR]

An undecylenic acid-based monoglyceride prepared from glycidol and undecylenic acid is used as suitable and tunable synthon for polymerization applications. Epoxidation and acrylation reactions lead to photopolymerizable monomers while transesterification with dimethyl carbonate, metathesis and aminolysis reactions provide access to polyhydroxyurethane-based materials. The successive intermediates were synthesized according to a green chemistry approach implicating solvent-less and catalyzed reactions, and were at each step fully characterized by infrared, 1 H and 13 C{ 1 H} NMR spectroscopy, elemental analysis and mass spectrometry. Analyses of the resulting polymer materials were performed by infrared, 1 H and 13 C{ 1 H} NMR, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and gel permeation chromatography (GPC). [ABSTRACT FROM AUTHOR]

Soy protein has shown potential as a renewable and environmentally friendly adhesive because of its superior performance and affordability compared with urea formaldehyde-based adhesives, but poor water resistance has limited its application as a high-performance wood adhesive comparable to phenol formaldehyde. This work focused on developing and characterizing undecylenic acid (UA)-modified soy proteins to improve their water resistance. The reaction between amine groups from protein and carboxyl groups from UA was proposed to be the main chemical pathway for grafting, which was proven by Fourier transform infrared spectroscopy (FTIR) and a ninhydrin test. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) showed that UA modification led to reduced thermal stability because of protein unfolding and decreased protein-protein cross-linkages. The increased attractive force between carbon chains of UA and protein residues resulted in higher viscosity and dynamic modulus values. Atomic force microscopy (AFM) images showed changes in protein particle size and surface properties. The wet strengths of modified soy protein adhesives were significantly improved by 35–62% compared with the control. UA with hydrophobic carbon chains and reactive carboxyl groups is an ideal bio-based modifier for soy proteins. [ABSTRACT FROM AUTHOR]

The main objectives of the present study were to investigate the biocompatibility of polyelectrolyte-coated nanocapsules and to evaluate the neuroprotective action of the nanoencapsulated water-insoluble neuroprotective drug—undecylenic acid (UDA), in vitro. Core-shell nanocapsules were synthesized using nanoemulsification and the layer-by-layer (LbL) technique (by saturation method). The average size of synthesized nanocapsules was around 80 nm and the concentration was 2.5 × 10 10 particles/ml. Their zeta potential values ranged from less than −30 mV for the ones with external polyanion layers through −4 mV for the PEG-ylated layers to more than 30 mV for the polycation layers. Biocompatibility of synthesized nanocarriers was evaluated in the SH-SY5Y human neuroblastoma cell line using cell viability/toxicity assays (MTT reduction, LDH release). The results obtained showed that synthesized nanocapsules coated with PLL and PGA (also PEG-ylated) were non-toxic to SH-SY5Y cells, therefore, they were used as nanocarriers for UDA. Moreover, studies with ROD/FITC-labeled polyelectrolytes demonstrated approximately 20% cellular uptake of synthetized nanocapsules. Further studies showed that nanoencapsulated form of UDA was biocompatible and protected SH-SY5Y cells against the staurosporine-induced damage in lower concentrations than those of the same drug added directly to the culture medium. These data suggest that designed nanocapsules might serve as novel, promising delivery systems for neuroprotective agents. [ABSTRACT FROM AUTHOR]

Undecylenic acid methyl ester (UAME) was continuously produced from methyl ricinoleate using a microwave-assisted pyrolysis system with atomization feeding. The UAME yield of 77 wt.% was obtained at 500 °C using SiC as the microwave absorbent and heating medium. The methyl ricinoleate conversion and UAME yield from microwave-assisted pyrolysis process were higher than those from conventional pyrolysis. The effect of temperature on the pyrolysis process was also investigated. The methyl ricinoleate conversion increased but the cracking liquid yield decreased when the temperature increased from 460 °C to 560 °C. The maximum UAME yield was obtained at the temperature of 500 °C. [ABSTRACT FROM AUTHOR]

The use of self-assembled organic monolayers as the insulator in light-addressable potentiometric sensors (LAPS) is shown for the first time. Silicon on sapphire (SOS) substrates were modified with 1-octadecene or undecylenic acid. Experiments with a photoresist pattern as the model system showed the same good spatial resolution that was previously obtained with a conventional insulator on SOS, but also a significant improvement in the photocurrent contrast and therefore the sensitivity of LAPS. Surface potential imaging was validated by studying micropatterns of poly(allylamine hydrochloride) (PAH) and DNA on a PAH template using LAPS. The results showed that self-assembled organic monolayers provide an excellent, reproducible, ultrathin insulator for LAPS, which can be readily functionalized and used for high-sensitivity LAPS imaging and sensing. [ABSTRACT FROM AUTHOR]