Dodecyl Sulfate Research Articles

Directed crystallization of a poly(3,4-ethylenedioxythiophene) film by an iron(III) dodecyl sulfate lamellar superstructure

Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), a successfully commercialized polymeric semiconductor material, has potential as a transparent electrode in flexible electronic devices, yet has insufficient conductivity. We present the synthesis, properties, and directed crystallization of the PEDOT:dodecyl sulfate (PEDOT:DS) film. Iron(III) dodecyl sulfate (Fe(DS)3) multi-lamellar vesicles (MLVs), a new growth template, are used to synthesize and direct the growth of the PEDOT:DS film via vapor-phase polymerization of 3,4-ethylenedioxythiophene to form huge PEDOT:DS co-crystal domains within the MLV superstructure. The polycrystalline film has metallic conductivity (avg. ~1.0 × 104 S cm−1), is highly transparent and mechanically durable yet flexible, and suitable for next-generation flexible electronics. These noteworthy properties are conferred by the MLV lamellar superstructure of Fe(DS)3, a selective oxidant and an efficient in situ dopant that enhances the film hydrophobicity and durability. Sophisticated MLV-type oxidants are foreseen to enable the synthesis of more conductive, transparent, robust, flexible, and water-stable polymer electrode materials in future.

Deciphering the Impact of Cyclization and Lysine Charges on Antimicrobial Peptides Using Molecular Dynamics Simulations and Density Functional Theory

AbstractThis study utilized molecular dynamics simulations (MD) to explore the impact of cyclization and lysine charges on antimicrobial peptides (AMPs) across eight simulation boxes designed with water and water‐sodium dodecyl sulfate (SDS) micelles. Cyclic AMPs with positively charged lysine residues (c‐AMP+) displayed increased stability in both environments compared to linear AMPs (l‐AMP+), with removal of positive charges notably destabilizing the linear form in water‐SDS. Findings revealed enhanced mobility due to cyclization and charged lysine residues, further boosted by SDS presence. Notably, lysine residues exhibited a stronger affinity for SDS than tryptophan and phenylalanine, especially lysine number 5. Analysis extended to peptide backbone conformation and electronic features, showing cyclization's greater impact on psi and phi angles over charge presence, with linear AMPs displaying lower reactivity than cyclic counterparts. This research underscores the significance of cyclization and lysine charges in AMP behavior, suggesting the potential of c‐AMP+ for further development owing to their improved stability, mobility, and membrane interactions.

Comprehensive profiling and authentication of porcine, bovine, and goat bone gelatins through UHPLC-HRMS metabolomics and chemometric strategies

Gelatin is a derivative that can be obtained from the bones of animals such as bovine, goat, and porcine. Ensuring the halal status of gelatin is crucial due to the combination of gelatin derived from bovines and goats mixed with porcine gelatin in order to enhance the stability of its physico-chemical properties for application in food and cosmetic applications. This study aims to authenticate the halal status of gelatin by utilizing the metabolomics analysis approach using UHPLC-HRMS in combination with chemometrics. The study's findings showed that PCA analysis clearly distinguished the metabolite profiles of bone gelatins obtained from porcine, bovine, and goat sources. Cluster analysis identified distinct metabolic characteristics in bone gelatins derived from bovine, goat, and porcine. Fifteen potential metabolites were identified by PLS-DA for the halal authentication of gelatin. These metabolites include terephthalic acid, 5,5'-[(6Z)-6-Tetradecene-1,14-diyl]bis (1,3-benzenediol), 1,2-Cyclohexane dicarboxylic acid diisononyl ester, 5-Hydroxymethyl-2-furaldehyde, D-(+)-Pyroglutamic acid, 4-Hydroxybenzaldehyde, Dodecyl sulfate, Bis(2-ethylhexyl)phthalate, Nicotinamide, dl-Malic acid, NP-011548, 4-Nitrocatechol, 1-Linoleoyl glycerol, Olomoucine, and Myristyl sulfate. The study findings indicated that bone gelatins derived from bovine, goat, and porcine sources exhibit distinct profiles of metabolites. Metabolomics, when paired with chemometrics, is a discriminative approach for determining the halal status of gelatin.

Surface-active ionic liquids as lubricant additives to hexadecane and diethyl succinate

The effectiveness of surface-active ionic liquids (SAILs) as lubricant additives in both polar and apolar base liquids has been investigated on stainless steel surfaces at both macroscale and nanoscale. The SAILs studied are composed of trihexyltetradecylphosphonium ([P6,6,6,14]+) cations paired with either dioctyl sulfosuccinate ([AOT]-) or dodecyl sulphate ([DS]-) anions. The polar and apolar base liquids used to dilute the SAILs are diethyl succinate ((CH2CO2Et)2) and hexadecane (HD), respectively. The friction coefficients of pure [P6,6,6,14] [AOT] and [P6,6,6,14] [DS] are up to ∼80 % lower than those of (CH2CO2Et)2 and HD. Remarkably, diluted solutions containing as little as 5 wt% SAIL in either (CH2CO2Et)2 or HD exhibit lubricity comparable to that of pure SAILs, revealing their excellent potential as lubricant additives. The high lubricity of the SAIL solutions in both (CH2CO2Et)2 and HD is attributed to the adsorption of anions onto the positively charged stainless steel surface, resulting in the formation of a robust boundary layer that reduces surface contact and facilitates smooth sliding. These insights aid the development of advanced, cost-effective lubricant additives, with potential applications across various industrial sectors.

In Situ Formed Organic Ion-Associate Liquid-Phase Microextraction without Centrifugation from Aqueous Solutions Using Thymol Blue and Estrogens

In this study, we present a method for ion-associated liquid phase (IALP) separation and concentration of analytes from an aqueous matrix into an IALP formed in situ by the charge neutralization reaction of organic cations and anions, without centrifugation. The effects of various factors on the extraction efficiency and other parameters are investigated, whereas no instrumental stirring, such as vortexing or ultrasonics, is required because the solvent (IALP) is formed in situ. The organic cation and anion used are ethylhexyloxypropylammonium and dodecyl sulfate, respectively. The developed in situ IALP microextraction method for phase separation without centrifugation is tested using the thymol blue dye and several endocrine disruptors. The tested endocrine disruptors (bisphenol A, 17β-estradiol, 17α-ethinylestradiol, and estrone) are analyzed via high-performance liquid chromatography/fluorescence detection, with respective detection limits of 0.02, 0.02, 0.02, and 0.4 μg L−1, and the corresponding enrichment factor ranging from 47 to 71. This IALP microextraction method can be used to separate and concentrate environmental water samples of different matrices. The employed IALP is fast and easy to use, enables an approximately 100-fold analyte concentration, and has a high affinity for estrogens, thus holding promise for the separation, concentration, and quantitation of diverse trace analytes.

Development, synthesis, and application of magnetic layered double hydroxides (Fe3O4@SiO-LDH/DS−) as an efficient adsorbent for the removal of tetracyclines from milk samples

This work presents the development, synthesis, and application of a layered double hydroxide (LDH) coupled to magnetic particles for the removal of antibiotics as tetracyclines (TC´s): tetracycline (TC), chlortetracycline (CT), oxytetracycline (OT), and doxycycline (DT) from milk samples. The LDH synthesis conditions, reaction time (30–90 min), molar ratios Mg2+/Al3+ (7:1–1:7), interlayer anion (NO3−, Cl−, CO32−, and dodecyl sulphate (DS−)) were evaluated. Under synthesis conditions (reaction time of 30 min, Mg2+/Al3+ molar ratio of 7:1, and DS− as interlayer anion), the LDH was coupled in a magnetic solid phase microextraction (MSPμE) methodology. At the optimal extraction conditions (pH 6, 5 min of contact time, 10 mg of adsorbent), a removal percentage of 99.0 % was obtained for each tetracycline. FTIR, TGA, SEM, and adsorption isotherms were employed to characterize the optimal adsorbent. Each experiment was corroborated by large-volume sample stacking capillary electrophoresis (LVSS-CE). The adsorbent was applied directly to positive milk samples (previously tested) for TC´s removal.

Interlayer anions modulated ZnAl-layered double hydroxides for enhanced photocatalytic CO2 reduction

Photocatalytic CO2 reduction has drawn widespread attention across all sectors of society. Layered double hydroxides (LDHs) have emerged as promising photocatalysts, renowned for their adjustable bandgaps and reaction sites. As a typical anionic layered material, LDHs exhibit intricate interactions between interlayer anions and brucite-like metal layers, greatly influencing their inherent physicochemical properties. In this work, we synthesized ZnAl-LDH samples intercalated with four distinct anions: carbonate (CO32–), chloridion (Cl–), nitrate (NO3–), and dodecyl sulfate (DS–), denoted as LDH-CO3, LDH-Cl, LDH-NO3, and LDH-DS, respectively. These LDHs samples have comparable crystallinity and morphology but differ in their interlayer spacing. XRD results reveal interlayer spacings of 0.77 nm for LDH-CO3, 0.78 nm for LDH-Cl, 0.88 nm for LDH-NO3, and 1.24 nm for LDH-DS, between adjacent brucite-like ZnAl hydroxide layers. Remarkably, LDH-NO3 demonstrates the highest photocatalytic CO2 reduction performance, with CO as the primary reduction product. Specifically, the average CO production rate of LDH-NO3 are 3.80 μmol g–1 h–1, surpassing that of LDH-CO3, LDH-Cl, and LDH-DS by 1.9, 2.1, and 2.5 times, respectively. This superior performance can be attributed to the intermediate interlayer spacing of LDH-NO3, which facilitates strong light absorption and a robust local built-in electric field. Theses properties enhance charge generation and separation abilities, leading to efficient photocatalytic reactions. The obtained results highlight the critical role of controlling small molecules within the interlayer, alongside defects, in the design and fabrication of layered-structure photocatalysts. This study provides valuable insights into optimizing the performance of LDH-based photocatalysts for CO2 reduction and potentially other photocatalytic applications.

Glutamate, glycine, and especially the secretions of Ruditapes phillipinarum induce efficient foraging by juvenile Rapa whelks

Chemical signals are known to influence interactions within and among species of aquatic organisms, including gastropods. However, despite the indispensable roles of chemical signals in species interactions, little is known about their effectiveness, especially in gastropods. The rapa whelk Rapana venosa (Valenciennes, 1846) is an ecologically and economically important gastropod, but it has also become a global invasive species. Currently, bottlenecks exist in the breeding of R. venosa related to foraging behaviour and efficiency in juveniles, while significant problems also exist in controlling invasive populations of the gastropod. Here, we aimed to identify chemical signaling molecules that could effectively improve their foraging behaviour and efficiency and potentially solve the bottlenecks in aquaculture production and control the invasiveness of R. venosa. The foraging behaviour of R. venosa during the search phase was evaluated in response to various signaling molecules as to activity time, motion path, and successful perception rate, and a standard scoring metric was proposed. The results showed that bivalve (Ruditapes philippinarum) secretion and glutamic acid and glycine, could effectively induce foraging behaviour in R. venosa. In contrast, 4-dodecylbenzene sulfonic acid and dodecyl sulfate, did not induce significant foraging behaviour. The induced foraging behaviour by a single amino acid was less effective than that of the entire bivalve secretion. These findings could be helpful in improving breeding efficiency, efficient trapping, and controlling invasive populations of aquatic gastropods.

Ni foam-supported Cu0.33Co0.67Se2 and modified NiCo-layered double hydroxide nanoarray composites for high-energy-density hybrid supercapacitors

High-performance supercapacitors, valued for their extended operational lifespan and remarkable power density, have garnered significant attention as potential energy storage solutions. Nevertheless, their practical application has been impeded by the limited energy density and unsatisfied rate capability of conventional electrode materials. To address these challenges, we developed an effective approach for crafting a composite material, featuring a core-shell nanostructure comprised of dodecyl sulfate (DS) ions intercalated Cu0.33Co0.67Se2/NiCo-DS-LDH nanostructures. The synergistic inter-component effect between copious active sites of Cu–Co–Se and DS-modified NiCo-LDH readily boosts the high specific capacity as ∼488 mAh g−1 at 1 A g−1 with an enhanced capacity retention of ∼36.3%. In this material system, the Cu0.33Co0.67Se2/NiCo-DS-LDH cathode-integrated hybrid supercapacitor device, with the N, S co-doped porous carbon anode achieves an energy density of ∼54.4 Wh kg−1 at a power density of ∼801 W kg−1. These exceptional electrochemical performances can be attributed to the combinatorial effect of the high conductivity of the Ni network, the high activity of the bimetallic selenide, and the expanded interlayer spacing of the NiCo-LDH. The current work presents a newly developed strategy for the design of promising transition metal-based composites with a rational architecture, offering significant potential for next-generation energy storage systems.

Dye‐Sensitized Solar Cell of Silicon Dioxide–Titanium Dioxide Photoanode With Polypyrrole/Sodium Dodecyl Sulfate Low‐Cost Counter Electrode

To produce a better connection and greater electron transfer efficiency between the TiO2 particles, as well as to eliminate agglomeration and increase the dispersion of TiO2 powders, a silicon dioxide/titanium dioxide (SiO2/TiO2) nanocomposite has been used as a photoanode in this study. An attempt was made to construct dye‐sensitized solar cells (DSSCs) at a low cost with reasonable efficiency by replacing the highly costly platinum counter electrode with polypyrrole/sodium dodecyl sulfate (PPy + SDS) as Counter Electrode 1 (C1) and PPy/SDS/multiwalled carbon nanotube (PPy + SDS + MWCNT) as Counter Electrode 2 (C2), using Ru‐based dyes Z907, pomegranate (Pom) dye, arugula (Aru) dye, and hibiscus dye as photosensitizers. The working electrode composite was deposited on fluorine‐doped tin oxide (FTO) glass using a thermal chemical spraying approach, while the counter electrodes were produced using an electropolymerization method. The structural and optical characteristics are fully examined using several characterization techniques such as X‐ray diffraction (XRD), Raman scattering, field‐emission scanning electron microscopy (FESEM), and atomic force microscopy (AFM). The photovoltaic properties of the constructed DSSCs were assessed under light irradiation (100 mW/cm2). When compared to the reference cell based on the Pt counter electrode, which has an efficiency of 8.4%, the measured current–voltage (I–V) curve shows that the efficiency of DSSC in the case of Z907 dye with C1 and C2 was 3.037% and 3.743%, respectively. This suggests that the low‐cost prepared DSSCs have good efficiency. Natural dyes show an efficiency range of 1.317%–0.66%, which indicates a moderate level of sensitivity.

Effect of equilibration time on the structural gradient in the vertical direction for bicontinuous microemulsions in Winsor-III and -IV systems.

Bicontinuous microemulsions (BMEs), self-assembly systems consisting of oil and water nanodomains separated by surfactant monolayers, have many applications. However, changes in structure and properties of BMEs in the vertical direction can affect BMEs' utility. This study's objective was to determine the effect of equilibration time (τeq) on structural changes in the vertical direction for bicontinuous phases of Winsor-III (WIII) systems in situ or after being isolated, for D2O + H2O/1-dodecane/sodium dodecyl sulfate (SDS)/1-pentanol/NaCl at 22 °C. Small-angle neutron scattering (SANS) measurements were performed using a vertical stage sample environment that precisely aligned samples in the neutron beam. SANS data were fitted by the Teubner-Strey (TS) model and changes in TS-derived parameter values were observed. For 10 min ≤ τeq ≤ 4 h, the effective activity of the bicontinuous phase's surfactant monolayers increased with time at all vertical positions. At short equilibration (τeq = 10 min), small but significant amounts of water and oil were transiently emulsified near the WIII upper liquid-liquid interface. WIII systems underwent a relaxation process after being transferred to narrow 1 mm pathlength cells, resulting in a decrease of surfactant activity for the top half of the bicontinuous phase. For isolated bicontinuous phases, results suggest that SDS was desorbed from the BMEs by quartz near the bottom, while near the top, the water concentration near was relatively high. The results suggest that WIII systems should equilibrate for at least 4 hours after being prepared and transferred to a container that differs in cross sectional area and surfactant behavior in BMEs can change near interfaces.

A triazolium-based fluorophore intercalated in layered double hydroxides: from simple syntheses to bright solid-state luminescence.

This study presents the intercalation into Layered Double Hydroxides (LDHs) of two sulfonated organic molecules featuring the mesoionic triazolium scaffold. These sulfonated fluorophores exhibited excellent solubility in aqueous basic solutions, facilitating their compatibility with the synthesis of LDHs through coprecipitation methods. We applied the size-matching interlayer space (SMIS) approach by substituting a portion of a mono- or dianionic surfactant used in LDH preparation by the sulfonated fluorophore, we aimed to match the size of the luminescent interleaved guest effectively. Our investigation focused on two anion spacers: the classic monoanionic dodecyl sulfate (DS) and the dianionic phenylene dipropionate (PPA). Our results indicated that the latter spacer allowed a more efficient insertion of the fluorescent guest. Thermal resistance analysis underscored the robustness of the final hybrid materials, suggesting a promising design strategy for luminescent materials when applied in diverse applications.

Optimizing cleaning strategies for biofouling in reverse osmosis membrane systems: A comparative study using a self-formed instrument

Membrane biofouling poses a serious challenge in reverse osmosis (RO) plants used for water recovery, which cannot be addressed by traditional chlorine-based cleaning agents. To accommodate this problem and enhance membrane performance while maintaining high-quality water production, various cleaning strategies have been applied. It remains however challenging to identify optimal cleaning agents, as tests require discontinuation of production to evaluate the effect. This study introduces a self-formed instrument that mimics industrial RO plants on a small scale to compare the cleaning agents in a fast, affordable and feasible approach. The setup was demonstrated using three cells operating in parallel and a thorough comparison of these. Specifically, the online cleaning efficiency of a typical biofouling cleaner, a solution of NaOH/sodium dodecyl sulfate (SDS), and the commonly used non-oxidizing biocide, 2,2-dibromo-3-nitrilopropionamide, were compared to validate the system performance when fed with membrane bioreactor effluent. The effectiveness of the cleaning process was evaluated using a combination of hydrodynamic operation and membrane autopsy to estimate the biofoulant amount and composition. During a 7-day operating period, it was observed that treated membranes demonstrated higher flux rates compared to untreated membranes. The normalized flux increased more than double in the membrane after it had been cleaned with NaOH/SDS solution. CLSM analysis clearly showed the distinct effects of the two cleaning solutions on the amount and spatial structure of the biofilm layer. Cleaning with DBNPA was able to reduce the load of living bacteria, but not necessarily remove the biofilm components completely. Comparative analyses of membranes revealed that NaOH/SDS exhibited the highest cleaning efficiency during the online cleaning operation mode. This benchmark highlights the versatility of the system, which can be assembled at relevant sites and assist in the identification of efficient and eco-friendly agents that promote the lifespan of membranes. With the distribution of this instrument, it will be possible to accelerate the investigation of multiple cleaning strategies and also analyze interactions among cleaning agents in an attempt to reduce water shortage.

Enhancing Metallocene Catalyst Activity: Utilizing Layered Double Hydroxide for Ethylene–Propylene Copolymerization

AbstractThis study reports the heterogenization of metallocene catalysts on sodium dodecyl sulfate (DDS)‐modified layered double hydroxides (LDHs) for efficient ethylene–propylene (EP) slurry‐phase copolymerization. The LDH support offers considerable compositional tunability. NiFe LDHs with different anions () and metallic compositions are applied as support for the metallocene catalysts; these significantly influence the catalytic properties of the heterogenized catalyst system. The supported‐catalyst intercalating DDS− anion in the galleries of NiFe and ZnAl LDHs demonstrates a high catalytic activity. They produce EP copolymers with high molecular weights (Mw) and wide polydispersity, compared with the homogeneous Zr catalyst. Further, the supported catalyst complex containing anion produces EP with a tenfold high Mw and demonstrate subdued catalytic activity. The higher basicity of the support is associated with the enhanced activity and the wider polydispersity of the EP pertaining to the different interactions of the catalyst molecule with the support. Overall, Ni‐containing LDH favors a higher activity, whereas Fe‐containing LDH favors a higher Mw. Therefore, NiFe‐based LDH results in both higher activity and molecular weight. 13C and 27Al magnetic angle spinning solid‐state nuclear magnetic resonance confirm the formation of the supported catalyst complex.

Effects of Charge Density on Spread Hyperbranched Polyelectrolyte/Surfactant Films at the Air/Water Interface.

The interfacial structure and morphology of films spread from hyperbranched polyethylene imine/sodium dodecyl sulfate (PEI/SDS) aggregates at the air/water interface have been resolved for the first time with respect to polyelectrolyte charged density. A recently developed method to form efficient films from the dissociation of aggregates using a minimal quantity of materials is exploited as a step forward in enhancing understanding of the film properties with a view to their future use in technological applications. Interfacial techniques that resolve different time and length scales, namely, ellipsometry, Brewster angle microscopy, and neutron reflectometry, are used. Extended structures of both components are formed under a monolayer of the surfactant with bound polyelectrolytes upon film compression on subphases adjusted to pH 4 or 10, corresponding to high and low charge density of the polyelectrolyte, respectively. A rigid film is related to compact conformation of the PEI in the interfacial structure at pH 4, while it is observed that aggregates remain embedded in mobile films at pH 10. The ability to compact surfactants in the monolayer to the same extent as its maximum coverage in the absence of polyelectrolyte is distinct from the behavior observed for spread films involving linear polyelectrolytes, and intriguingly evidence points to the formation of extended structures over the full range of surface pressures. We conclude that the molecular architecture and charge density can be important parameters in controlling the structures and properties of spread polyelectrolyte/surfactant films, which holds relevance to a range of applications, such as those where PEI is used, including CO2 capture, electronic devices, and gene transfection.

Atomic-scale insight into molecular adsorption of sodium dodecyl sulfate (SDS) on ideal bcc-Fe surface: A first-principles investigation

Adsorption is the most significant first step for boundary lubrication film formation, catalysis and chemical synthesis processes. Nevertheless, at present, the adsorption process and its mechanism of dodecyl sulfate (DS) molecules on solid surfaces are largely conjectured. Here, adsorption properties of DS on clean ideal bcc-Fe surfaces have been computational investigated via first principles method at atomic scale. At ground state, adsorption energies Eads are ranged from -11.75 eV to -3.09 eV. Adsorption Fe-O bond is a mixture of ionic bond and covalent one. Bond strength is affected by interfacial electron transfer and its stability is related to electron gain/loss of sub-interfacial atoms. Boltzmann distributions of adsorption conformations are calculated by partition functions that only depend on relative energies, and they are used as weight coefficients to estimate mixed-Eads. The temperature-induced Fermi-softness SF is calculated to reveal relationship between Eads and SF. Considered about solvent and temperature effects, the competitive adsorption and thermal activation can reduce the difference of adsorption energy barriers between conformations. Their adsorption probabilities become closer with the distribution proportion increase of the conformations with low Eads. This can provide theoretical foundations for further understanding of boundary lubrication film formation mechanism.

Preparation of PLA/PEG@SDS microfibers‐based nonwovens via melt‐blown process parameters: Wound dressings with enhanced water wetting performance

AbstractPolylactic acid (PLA) melt‐blown nonwovens are promising materials for medical and healthcare applications due to their properties such as softness, breathability, biodegradability, and biocompatibility. However, their widespread commercial application has been limited by their poor mechanical properties and insufficient hydrophilicity limit. To address these limitations, we prepared polylactic acid/polyethylene glycol@sodium dodecyl sulfate (PLA/PEG@SDS) microfibers‐based nonwovens using a melt‐blown process. The average fiber diameter of PLA/PEG@SDS microfibers nonwovens could be tuned from 1 to 13.9 μm by regulating the die temperature or hot air pressure. In addition, increasing the die temperature from 210°C to 225°C resulted in a 140.3% and 124.8% increase in the breaking resistance along the mechanical direction (MD) and transverse direction (CD), respectively. Meanwhile, the increase in the breaking resistance was observed between the hot air pressure and the mechanical strength of the PLA/PEG@SDS microfibers‐based nonwovens. Notably, the prepared samples exhibited a short wetting time of 3.438 s, a fast water absorption rate of 68.401%·s−1, and an excellent liquid water diffusion of 5.86 mm s−1. These results suggest that the PLA/PEG@SDS microfibers nonwovens prepared using melt‐blown process demonstrate efficient wetting performance, which paves the way for the industrial production of medical‐grade materials such as wound dressings.

Development of Berberine-Loaded Nanoparticles for Astrocytoma Cells Administration and Photodynamic Therapy Stimulation.

Berberine (BBR) is known for its antitumor activity and photosensitizer properties in anti-cancer photodynamic therapy (PDT), and it has previously been favorably assayed against glioblastoma multiforme (GBM)-derived cells. In this work, two BBR hydrophobic salts, dodecyl sulfate (S) and laurate (L), have been encapsulated in PLGA-based nanoparticles (NPs), chitosan-coated by the addition of chitosan oleate in the preparation. NPs were also further functionalized with folic acid. All the BBR-loaded NPs were efficiently internalized into T98G GBM established cells, and internalization increased in the presence of folic acid. However, the highest mitochondrial co-localization percentages were obtained with BBR-S NPs without folic acid content. In the T98G cells, BBR-S NPs appeared to be the most efficient in inducing cytotoxicity events and were therefore selected to assess the effect of photodynamic stimulation (PDT). As a result, PDT potentiated the viability reduction for the BBR-S NPs at all the studied concentrations, and a roughly 50% reduction of viability was obtained. No significant cytotoxic effect on normal rat primary astrocytes was observed. In GBM cells, a significant increase in early and late apoptotic events was scored by BBR NPs, with a further increase following the PDT scheme. Furthermore, a significantly increased depolarization of mitochondria was highlighted following BBR-S NPs' internalization and mostly after PDT stimulation, compared to untreated and PDT-only treated cells. In conclusion, these results highlighted the efficacy of the BBR-NPs-based strategy coupled with photoactivation approaches to induce favorable cytotoxic effects in GBM cells.

Study on the preparation and properties of acellular matrix from the skin of silver carp (Hypophthalmichthys molitrix).

Acellular matrices are mainly composed of mammalian tissues, and aquatic tissues with lower biological risks and less religious restrictions are considered alternatives to mammalian tissues. The acellular fish skin matrix (AFSM) has been commercially available. Silver carp has the advantages of farmability, high yield and low price, but there are few studies on the silver carp acellular fish skin matrix (SC-AFSM). In this study, an acellular matrix with low DNA and endotoxin was prepared from the skin of silver carp. After treatment with trypsin/sodium dodecyl sulfate and Triton X-100 solutions, the DNA content in SC-AFSM reached 11.03 ± 0.85 ng/mg, and the endotoxin removal rate was 96.8%. The porosity of SC-AFSM was 79.64% ± 0.17%, which is favorable for cell infiltration and proliferation. The relative cell proliferation rate of SC-AFSM extract was 117.79% ± 15.26%. The wound healing experiment showed that SC-AFSM had no adverse acute pro-inflammatory response, which had a similar effect as commercial products in promoting tissue repair. Therefore, SC-AFSM has great application potential in biomaterials.

INFLUENCE OF THE PHASE TRANSFER CATALYST ON THE ACCUMULATION AND DECOMPOSITION OF ETHYLBENZENEHYDROPEROXIDE

The regularities of ethylbenzene oxidation and hydroperoxide decomposition in microheterogeneous systems formed by adding sodium dodecyl sulphate to hydrocarbon media have been studied. A pronounced influence of surfactant nature on the transformation mechanism has been revealed. Anionic micellar surfactants including a linear hydrocarbon fragment catalytically accelerate ROOH decomposition, whereas hydrocarbon soluble non-ionic surfactants and solid oxides practically do not influence the reaction rate. Detailed study of the degradation kinetics in the presence of anionic alkyl sulphates has shown that the accelerating effect of surfactants is connected with their colloidal properties, namely, with the formation of joint aggregates of inverse micelles type, which facilitate the destruction of the peroxide bond. For the first time, a synergistic inhibitory effect of sodium alkyl sulphate mixtures with phenolic antioxidants in the oxidation of various hydrocarbons has been found. During the oxidation of ethylbenzene with minor additives (<1%) of sodium dodecyl sulphate (DDS) a unique case of effective self-inhibition has been determined, the mechanism of which includes two steps. Hydroperoxide, the main source of free radicals, decomposes heterolytically in joint microaggregates with DDS. The decomposition occurs selectively with the formation of acetaldehyde and phenol. Phenol being an acceptor of free radicals inhibits the oxidation of ethyl benzene. The main oxidation product of RH in this system is phenol and acetaldehyde. It should be noted that phenols formation at decomposition of alkylaromatic ROOH is usually connected with strong acids. In the case of DDS decomposition of ROOH seems to be driven by the successful orientation of ROOH molecules in the microaggregates formed by anionic surfactants. But a number of experimental factors, namely the influence of the carbon chain length in sodium alkyl sulphates on the dodecane oxidation rate and inertness of the Na2SO4 dispersion in the hydroperoxide decomposition reactions, make it possible to suggest the catalytic reaction of ROOH. Suggest that the catalytic effect of DDS on hydroperoxide decomposition is connected with its colloidal properties and decomposition occurs in common microaggregates formed by DDS and ROOH. The effective activation energy of ROOH decomposition at concentration of 10 mm is Eef = 66.3 kJ/mol. The oxidation of ethyl benzene is completely inhibited at low additions of DDS (1 mM), and the decomposition rate in an atmosphere of N2 significantly increases. DDS increases the effective decomposition constant of ROOH. This surfactant can be considered as an effective catalyst of ROOH decomposition. For citation: Kashkay A.M. Influence of the phase transfer catalyst on the accumulation and decomposition of ethylbenzenehydroperoxide. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 2. P. 100-106. DOI: 10.6060/ivkkt.20236602.6684.