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Biodegradable composites consisting of Poly-(butylene adipate-co-terephthalate) (PBAT), thermoplastic starch, hydrophobically modified nanofibrillated cellulose (HMNC), and green surfactant (sucrose fatty acid ester) were prepared via the melt-mixing and film-blowing process (PBAT-HMNC). The composites were characterized using the Fourier transform infrared spectroscope (FT-IR), scanning electron microscope (SEM), and thermogravimetric analyzer (TGA). The mechanical and barrier properties were systematically studied. The results indicated that PBAT-HMNC composites exhibited excellent mechanical and barrier properties. The tensile strength reached the maximum value (over 13 MPa) when the HMNC content was 0.6% and the thermal decomposition temperature decreased by 1 to 2 °C. The lowest values of the water vapor transmission rate (WVTR) and the oxygen transmission rate (OTR) were obtained from the composite with 0.6 wt% HMNC, prepared via the film-bowing process with the values of 389 g/(m2·day) and 782 cc/(m2·day), which decreased by 51.3% and 42.1%, respectively. The Agaricus mushrooms still had a commodity value after 11 days of preservation using the film with 0.6 wt% HMNC. PBAT-HMNC composites have been proven to be promising nanocomposite materials for packaging.

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Biosurfactants are naturally occurring amphiphiles that are being actively pursued as alternatives to synthetic surfactants in cleaning, personal care, and cosmetic products. On the basis of their ability to mobilize and disperse hydrocarbons, biosurfactants are also involved in the bioremediation of oil spills. Rhamnolipids are low molecular weight glycolipid biosurfactants that consist of a mono- or di-rhamnose head group and a hydrocarbon fatty acid chain. We examine here the micellization of purified mono-rhamnolipids and di-rhamnolipids in aqueous solutions and their adsorption on model solid surfaces. Rhamnolipid micellization in water is endothermic; the CMC (critical micellization concentration) of di-rhamnolipid is lower than that of mono-rhamnolipid, and both CMCs decrease upon NaCl addition. Rhamnolipid adsorption on gold surface is mostly reversible and the adsorbed layer is rigid. A better understanding of biosurfactant self-assembly and adsorption properties is important for their utilization in consumer products and environmental applications.

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Triderm® cream and ointment contain clotrimazole (CLO), betamethasone dipropionate (BET), and the poor UV absorbing gentamycin (GEN), in addition to the preservative benzyl alcohol (BEN) which exists only in a cream preparation. A green, selective colorimetric approach was elaborated to increase the sensitivity of GEN quantification in Triderm® preparations, which depends on the immediate formation of a pink ion-pair between GEN and erythrosine (ERY) reagent in an aqueous acidic medium. The ion pair was made soluble in water with the assistance of the surfactant agent poloxamer 188 which is presented in this manuscript as an efficient solubilizing agent for the hydrophobic ion-pair. This surfactant agent has the feature of not affecting the native color of ERY, additionally the ease of preparing its aqueous solution with no need for heating or long waiting. The resulting complex GEN-ERY was measured directly at 545nm. This colorimetric approach was coupled with the Unlimited Derivative Ratio (UDD), which is a new smart UV method employed for the concurrent quantification of BET and CLO in Triderm® preparations without any intervention from BEN, due to its capability to resolve an extremely overlapped ternary spectrum that has no extended part, iso-absorptive point or robust zero crossing point. The newly developed UDD method depends on filtrating and measuring the signal of BET and CLO through calculating the equality factor(F) for CLO and BET after dividing their spectrum by BEN spectrum, derivatizing the resulting ratio spectrum, then constructing a regression equation employing the F factor for each BET and CLO. The overlapping excipient BEN was quantified via the Double Divisor Ratio spectra derivative method (DDR) relying on using a divisor comprising of a mix of BET + CLO. The advanced spectrophotometric approach validity was checked by confirming the linearity, accuracy, precision, and specificity in accordance with the ICH directions. NO notable difference when statistically comparing the newly established approach to the reference approach.

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Green enhanced oil recovery (GEOR) is an eco-friendly EOR technique involving the injection of specific green fluids to improve macroscopic and microscopic sweep efficiencies, boosting residual oil production. The environmentally friendly surfactant-polymer (SP) flood is successfully tested in a sandstone reservoir. However, the applicability of the SP method does not extend to carbonate reservoirs yet and requires comprehensive investigation. This work aims to explore the oil recovery competency of a green SP formulation in carbonate through experimental and modelling studies. Numerous formulations of SP with ketone, alcohol, and organic acid are selected based on phase behavior and interfacial tension (IFT) reduction capabilities to examine their potential for enhancing residual oil production from carbonate cores. A blending of nonionic green surfactant alkyl polyglucoside (APG), xanthan gum (XG) biopolymer, and butanone recovered 22% tertiary oil from the carbonate core. This formulation recovered more than double residual crude than that of the APG, XG, and acetone. Similarly, a combination of APG, XG, acrylic acid, and butanol increased significantly more oil than the APG, XG, and acrylic acid formulation. The APG, XG, and butanone mixture is efficient with regards to boosting tertiary oil recovery from the carbonate core.

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Green enhanced oil recovery is an oil recovery process involving the injection of specific environmentally friendly fluids (liquid chemicals and gases) that effectively displace oil due to their ability to alter the properties of enhanced oil recovery. In the microbial enhanced oil recovery (MEOR) process, microbes produce products such as surfactants, polymers, ketones, alcohols, and gases. These products reduce interfacial tension and capillary force, increase viscosity and mobility, alter wettability, and boost oil production. The influence of ketones in green surfactant-polymer (SP) formulations is not yet well understood and requires further analysis. The work aims to examine acetone and butanone's effectiveness in green SP formulations used in a sandstone reservoir. The manuscript consists of both laboratory experiments and simulations. The two microbial ketones examined in this work are acetone and butanone. A spinning drop tensiometer was utilized to determine the interfacial tension (IFT) values for the selected formulations. Viscosity and shear rate across a wide range of temperatures were measured via a Discovery hybrid rheometer. Two core flood experiments were then conducted using sandstone cores at reservoir temperature and pressure. The two formulations selected were an acetone and SP blend and a butanone and SP mixture. These were chosen based on their IFT reduction and viscosity enhancement capabilities for core flooding, both important in assessing a sandstone core's oil recovery potential. In the first formulation, acetone was mixed with alkyl polyglucoside (APG), a non-ionic green surfactant, and the biopolymer Xanthan gum (XG). This formulation produced 32% tertiary oil in the sandstone core. In addition, the acetone and SP formulation was effective at recovering residual oil from the core. In the second formulation, butanone was blended with APG and XG; the formulation recovered about 25% residual oil from the sandstone core. A modified Eclipse simulator was utilized to simulate the acetone and SP core-flood experiment and examine the effects of surfactant adsorption on oil recovery. The simulated oil recovery curve matched well with the laboratory values. In the sensitivity analysis, it was found that oil recovery decreased as the adsorption values increased.

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Combination therapy, which combines anti-cancer drugs with different oligonucleotides, have shown potential in cancer treatment. However, delivering a hydrophobic anti-cancer drug and a hydrophilic oligonucleotide simultaneously is a herculean task. This study takes advantage of interactions between histidine-lauric acid-based green surfactant and poly(amidoamine) dendrimers to achieve this aim. The green surfactant was synthesized by carbodiimide chemistry and characterized by FTIR, 1H-NMR, and mass spectroscopy. Further, green surfactant-dendrimer aggregates encapsulating DTX and complexing SIRT 1 shRNA i.e., "aggreplexes" were developed and characterized. The term "aggreplexes" signifies complexes which are formed between green-surfactant-dendrimer aggregates and SIRT-1 shRNA via electrostatic interaction. The aggreplexes displayed particle size of 262.33 ± 3.87 nm, PDI of 0.25 and entrapment efficiency of 70.56 %. The TEM images revealed spherical shape of aggreplexes with irregular outer surface and corroborated particle size obtained from zetasizer. The in-vitro release study revealed biphasic release patterns of DTX from aggreplexes and were compatible for intravenous administration. Further, aggreplexes augmented cellular uptake in MDA-MB-231 cells by ∼1.87-fold compared to free DTX. Also, EGFP expression revealed significantly higher transfection of aggreplexes compared to naked shRNA and Superfect™ complexes. Further, aggreplexes showed higher cytotoxicity in MDA-MB-231 cells and ∼4.16-fold reduction in IC50 value compared to free DTX. Finally, apoptosis-index observed in case of aggreplexes was ∼3.57-fold higher than free DTX. These novel aggreplexes showed increased drug loading capacity and superior gene transfection potential. Thus, they open new avenues for co-delivery of hydrophobic anti-cancer drugs and hydrophilic therapeutic genes for improving current standards of cancer therapy.

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In this work, the effectiveness of a biodegradable and natural surfactant synthesized through a novel method has been studied through the ion flotation process to treat waters containing Per/Poly Fluoroalkyl Substances (PFAS) and heavy-metal ions. This cysteine-based surfactant, which is environmentally acceptable, showed considerable solubility and foaming ability over a wide range of pH. It also could remove 97-99(%) of 5 mg/L of cadmium, chromium, copper, nickel, zinc, and manganese ions in a single batch physicochemical process. Moreover, for the first time, a foam fractionation method in association with using this cysteine-based surfactant was applied for perfluorooctanoic acid (PFOA) removal from water. This surfactant was used as a co-surfactant and could readily remove 72% of PFOA (40 mg/L) from water. The characterization of the surfactant was undertaken using 1H NMR, FT-IR, elemental analysis, melting point, and determination of its critical micelle concentration (CMC). This environmentally friendly surfactant has high potential applications in green chemistry especially in the treatment of waters contaminated with PFAS/heavy-metal ions.

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An improved method has been developed for the efficient synthesis of octanoyl-cysteine in single-chain form (N-octanoyl-cys) which operates as a surfactant over a wide pH range, is easily decomposed into natural products and has a high product yield. The compound offers an environmentally acceptable agent for the adsorption of a range of heavy metals from contaminated waters/soils, and it could also be used in general household detergents or personnel-cleaner formulations, and even in toothpastes. The surfactant was used as a co-surfactant for flotation of perfluorooctanoic acid (PFOA), a per/poly-fluoroalkyl substance (PFAS). The new surfactant produced significant foaming and removed 70% of the PFOA after 30min of foam fractionation. The compound is also potentially useful in facilitating the release of PFAS compounds; these are negatively charged and often bound to charged particles in sand, clay, and humic-acid-coated materials and microorganisms via bridging multivalent ions, such as Ca2+, Mg2+, Al3+ and Fe3+, as well as a range of other heavy-metal ions present in soil to varying degrees. In soils (and also in contaminated water), the common chelating agent EDTA is often used to encapsulate these ions (e.g. Ca2+, the dominant ion in soil) at moderately high pH to aid in the release of the bound PFAS compounds. However, it would be more environmentally acceptable to use this new biodegradable surfactant, which could combine chelation with foam-fractionation separation of surface-active (e.g. PFAS) components in soils.

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Polyglycerol esters (PGEs), produced by esterification of fatty acids on polyglycerols, were analysed by High Resolution Mass Spectrometry (HRMS), HPLC-MS and U-HPLC-MS. A structural study of PGEs in 4 samples synthesised by the Gattefossé company was carried out using an elemental analysis of HRMS spectra and modelling of all probable isomers and cyclic structures. The results were used to construct a structural database of all species present in the 4 samples. After an assessment of the selectivity of 5 reversed phase columns: Aeris Widepore XB-C8, 3.6 µm, 2.1 × 150 mm (Phenomenex), Acquity CSH C18 1.7 µm 2.1 × 50 mm, Acquity CSH Phenyl-Hexyl 1.7 µm 2.1 × 50 mm, Acquity CSH Fluoro-Phenyl 1.7 µm 2.1 × 50 mm (Waters Co.) and Kinetex F5 1.7 µm 2.1 × 100 mm (Phenomenex), HPLC-MS and U-HPLC-MS analyses were performed on an Aeris Widepore XB-C8 (Phenomenex) column (HPLC) and Acquity CSH Fluoro-Phenyl (Waters) column (U-HPLC) with aqueous formic acid /acetonitrile in gradient mode. The separation was optimised with 10 min (HPLC) and 5 min (U-HPLC) of gradient. The detection, performed on a QDA detector (Waters), produced extracted ion chromatograms (XICs) based on all adducts identified in the HRMS analysis. HPLC and U-HPLC analyses showed the different mono- and di-ester species and provided relative quantification of all identified constituents. The combined analyses of the HRMS, HPLC-MS and U-HPLC-MS results were used to compare the different PGE batches and quantify the molecular constituents according to their relative abundance, for these complex mixtures. With HPLC and U-HPLC analyses, using 2 different gradient times and 2 different selectivity columns, and comparing the retention factors and log P of the different species, it was possible to link structural identification and relative quantification of all PGEs identified in the samples.

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A multi technique approach was utilized to explore the interaction between a novel green gemini surfactant, ethane-1,2-diyl bis(N,N-dimethyl-N-tetradecylammoniumacetoxy) dichloride (14-E2-14), with bovine milk xanthine oxidase (XO). Tensiometric, spectroscopic, microscopic and molecular modeling results demonstrate significant interaction and structural change of native xanthine oxidase upon 14-E2-14 combination. The results obtained in this study may be beneficial for scientists to calibrate conformation of the enzyme by novel biodegradable/green microstructures; consequently, it would likely add new impetus in understanding the treatment modes of various diseases like gout, hyperuricemia, liver and brain necrosis. Moreover, the 14-E2-14-XO interaction assists to unfurl new routes in the designing/selection of green-surfactant-protein mixtures widely used in food processing, cosmetics, and pharmaceutical industries.

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