We report about the first Raman spectroscopy study of a vesicle-assisted enzyme-catalyzed oligomerization reaction. The aniline dimer N-phenyl-1,4-phenylenediamine (= p-aminodiphenylamine, PADPA) was oxidized and oligomerized with Trametes versicolor laccase and dissolved O2 in the presence of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) vesicles (80–100 nm diameter) as templates. The conversion of PADPA into oligomeric products, poly(PADPA), was monitored during the reaction by in situ Raman spectroscopy. The results obtained are compared with UV/vis/NIR and EPR measurements. All three complementary methods indicate that at least some of the poly(PADPA) products, formed in the presence of AOT vesicles, resemble the conductive emeraldine salt form of polyaniline (PANI-ES). The Raman measurements also show that structural units different from those of “ordinary” PANI-ES are present too. Without vesicles PANI-ES-like products are not obtained. For the first time, the as-prepared stable poly(PADPA)-AOT vesicle suspension was used directly to coat electrodes (without product isolation) for investigating redox activities of poly(PADPA) by cyclic voltammetry (CV). CV showed that poly(PADPA) produced with vesicles is redox active not only at pH 1.1–as expected for PANI-ES–but also at pH 6.0, unlike PANI-ES and poly(PADPA) synthesized without vesicles. This extended pH range of the redox activity of poly(PADPA) is important for applications.

Considering a growing demand for medicinal/cosmetic products with natural actives, this study focuses on the low-energy nanoemulsions (LE-NEs) prepared via the Phase inversion composition (PIC) method at room temperature as potential carriers for natural oil. Four different red raspberry seed oils (ROs) were tested, as follows: cold-pressed vs. CO 2extracted, organic vs. non-organic, refined vs. unrefined. The oil phase was optimized with Tocopheryl acetate and Isostearyl isostearate, while water phase was adjusted with either glycerol or an antioxidant hydro-glycolic extract. This study has used a combined approach to formulation development, employing both conventional methods (pseudo-ternary phase diagram − PTPD, electrical conductivity, particle size measurements, microscopical analysis, and rheological measurements) and the methods novel to this area, such as textural analysis and Raman spectroscopy. Raman spectroscopy has detected fine differences in chemical composition among ROs, and it detected the interactions within nanoemulsions. It was shown that the cold-pressed, unrefined, organic grade oil (RO2) with 6.62% saturated fatty acids and 92.25% unsaturated fatty acids, was optimal for the LE-NEs. Textural analysis confirmed the existence of cubic gel-like phase as a crucial step in the formation of stable RO2-loaded LE-NEs, with droplets in the narrow nano-range (125 to 135 nm; PDI � 0.1). The DPPH test in methanol and ABTS in aqueous medium have revealed a synergistic free radical scavenging effect between lipophilic and hydrophilic antioxidants in LE-NEs. The nanoemulsion carrier has improved the biological effect of raw materials on HeLa cervical adenocarcinoma cells, while exhibiting good safety profile, as confirmed on MRC-5 normal

The literature concerning the oxidative oligomerization and polymerization of various arylamines, e.g., aniline, substituted anilines, aminonaphthalene and its derivatives, catalyzed by oxidoreductases, such as laccases and peroxidases, in aqueous, organic, and mixed aqueous organic monophasic or biphasic media, is reviewed. An overview of template-free as well as template-assisted enzymatic syntheses of oligomers and polymers of arylamines is given. Special attention is paid to mechanistic aspects of these biocatalytic processes. Because of the nontoxicity of oxidoreductases and their high catalytic efficiency, as well as high selectivity of enzymatic oligomerizations/polymerizations under mild conditions—using mainly water as a solvent and often resulting in minimal byproduct formation—enzymatic oligomerizations and polymerizations of arylamines are environmentally friendly and significantly contribute to a “green” chemistry of conducting and redox-active oligomers and polymers. Current and potential future applications of enzymatic polymerization processes and enzymatically synthesized oligo/polyarylamines are discussed.

A laccase-catalysed oligomerisation of p-aminodiphenylamine was investigated in an aqueous medium containing 80–100 nm-sized anionic vesicles formed from AOT, the sodium salt of bis(2-ethylhexyl)sulfosuccinic acid.

Many previous studies have shown that (i) the oxidation of aniline or the aniline dimer p -aminodiphenylamine (PADPA) in a slightly acidic aqueous solution can be catalyzed with heme peroxidases or multicopper laccases and that (ii) subsequent reactions lead to oligomeric or polymeric products, which resemble chemically synthesized polyaniline in its conductive emeraldine salt form (PANI-ES), provided that (iii) an anionic “template” is present in the reaction medium. Good templates are anionic polyelectrolytes, micelles, or vesicles. Under optimal conditions, their presence directs the reactions in a positive way toward the desired formation of PANI-ES-type products. The effect of four different types of anionic templates on the formation of PANI-ES-like products from PADPA was investigated and compared by using Trametes versicolor laccase (TvL) as a catalyst in an aqueous pH 3.5 solution at room temperature. All four templates contain sulfonate groups: the sodium salt of the polyelectrolyte sulfonated polystyrene (SPS), micelles from sodium dodecylbenzenesulfonate (SDBS), vesicles from a 1:1 molar mixture of SDBS and decanoic acid, and vesicles from sodium bis(2-ethylhexyl)sulfosuccinate (AOT). Although with all four templates, stable, inkjet-printable solutions or suspensions consisting of PANI-ES-type products were obtained under optimized conditions, considerably higher amounts of TvL were required with SDBS micelles to achieve comparable monomer conversion to PANI-ES-like products during the same time period when compared to those with SPS or the two types of vesicles. This makes SDBS micelles less attractive as templates for the investigated reaction. In situ UV/vis/near-infrared, electron paramagnetic resonance (EPR), and Raman spectroscopy measurements in combination with an high-performance liquid chromatography analysis of extracted reaction products, which were deprotonated and chemically reduced, showed seemingly small but significant differences in the composition of the mixtures obtained when reaching reaction equilibrium after 24 h. With the two vesicle systems, the content of unwanted substituted phenazine units was lower than in the case of SPS polyelectrolyte and SDBS micelles. The EPR spectra indicate a more localized, narrower distribution of electronic states of the paramagnetic centers of the PANI-ES-type products synthesized in the presence of the two vesicle systems when compared to that of the similar products obtained with the SPS polyelectrolyte and SDBS micelles as templates. Overall, the data obtained from the different complementary methods indicate that with the two vesicle systems structurally more uniform (regular) PANI-ES-type products formed. Among the two investigated vesicle systems, for the investigated reaction (oxidation of PADPA with TvL and O 2 ), AOT appears a somewhat better choice as it leads to a higher content of the PANI-ES polaron form.

This study focuses on the development of biocompatible oil-in-water (O/W) nanoemulsions based on polyglycerol esters, as promising carriers for natural actives: red raspberry seed oil—RO and hydro-glycolic fruit extracts from red raspberry—RE and French oak—FE. Nanoemulsions were obtained via phase inversion composition (PIC) method at room temperature by dilution of microemulsion phase, confirmed by visual appearance, percentage of transmittance, microscopic, rheological and differential scanning calorimetry (DSC) investigations. The results have shown that the basic RO-loaded formulation could be further enriched with hydro-glycolic fruit extracts from red raspberry or French oak, while keeping a semi-transparent appearance due to the fine droplet size (Z-ave: 50 to 70 nm, PDI value ≤ 0.1). The highest antioxidant activity (~92% inhibition of the DPPH radical) was achieved in the formulation containing both lipophilic (RO) and hydrophilic antioxidants (FE), due to their synergistic effect. The nanoemulsion carrier significantly increased the selective cytotoxic effect of RO towards malignant melanoma (Fem-X) cells, compared to normal human keratinocytes (HaCaT). In vivo study on human volunteers showed satisfactory safety profiles and significant improvement in skin hydration during 2 h after application for all nanoemulsions. Therefore, polyglycerol ester-based nanoemulsions can be promoted as effective carriers for red raspberry seed oil and/or hydro-glycolic fruit extracts in topical formulations intended for skin protection and hydration.

An undergraduate electrical conductivity measurement experiment in a physical chemistry lab and basic fitting procedures are presented that allow a characterization of micellar system of hexadecyltrimethylammonium bromide (cetyltrimethylammonium bromide, CTAB) in binary mixture of water and acetonitrile (ACN) as a cosolvent (10%, v/v) at 30.0 °C. Conductivity–concentration data were processed by inbuilt function of ORIGIN software to attain the values of critical micelle concentration by method of integration. Acquiring the data-fitting skills that are developed through the addition of a computational tool to a conventional electrical conductometry experiment has a general significance for its applications to more complex upper-level experiments with the aim to process data and perform fast calculations and graphics.

Energy demands of modern society require efficient means of energy conversion and storage. Nanocarbons have been identified as versatile materials which combine many desirable properties, allowing them to be used in electrochemical power sources, from electrochemical capacitors to fuel cells. Efficient production of nanocarbons requires innovative and scalable approaches which allow for tuning of their physical and chemical properties. Carbonization of polymeric nanostructures has been demonstrated as a promising approach for production of high-performance nanocarbons with desired morphology and variable surface chemical properties. These materials have been successfully used as active electrode materials in electrochemical capacitors, as electrocatalysts or catalyst supports. Moreover, these materials are often found as parts of composite electrode materials where they play very important role in boosting materials performance. In this contribution we shall review developments in the field of application of polymer-derived nanocarbons for electrochemical energy conversion and storage applications, covering the last decade. Primary focus will be on polyaniline and polypyrrole but carbons derived from other polymers will also be mentioned. We shall emphasize the link between the physical and chemical properties of nanocarbons and their performance in electrochemical power sources with an attempt to derive general guidelines for further development of new materials with improved performances.Keywords: polymer-derived carbons; electrochemical energy conversion; fuel cells; batteries; electrochemical capacitors century. These EPS can be generally classified in three categories: (i) electrochemical capacitors (supercapacitors), (ii) batteries and (iii) fuel cells [1]. The main properties of these EPSs are summarized in Table 1. Table 1. Properties of EPS along with the mechanisms of energy conversion EPS power density / W kg −1 Energy density / Wh kg −1 energy conversion mechanismprocess takes place at polymers has recently been pointed out as an elegant route to various carbon materials with desired structure and morphology [6][7][8]. Considering available literature, two polymers are the most common in this type of research: polyaniline (PANI) and polypyrrole (PPy). The conversion of polyaniline and polypyrrole into carbon materials and their application in electrochemistry seems rather natural. First, these two polymeric materials are intensively studied for years and the mechanism of polymerization under various conditions are known, as well as the possibility to tailor the morphology. There are several reviews on the chemistry and application of these materials available [9][10][11][12].However, what we consider to be the most important is the fact that both polyaniline and polypyrrole are conductive polymers which are applied in electrochemistry for quite a while, so, colloquially speaking, there were already at the right place in the right time.Nevertheless, these two polymers are not the only ones used to prod...