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A novel nanoporous adsorbent was obtained through the thermal treatment and chemical wash of the wasted crab shells (BC1) and characterized by various techniques. The structure of BC1 at the end of the treatments comprised a mixture of calcite and amorphous CaCO3, as evidenced by X-ray diffraction and Fourier transform infrared absorption. The BET surface area, BET pore volume, and pore diameter were 250.33 m2 g−1, 0.4 cm3 g−1, and <70 nm, respectively. The point of zero charge of BC1 was determined to be around pH 9. The prepared adsorbent was tested for its adsorption efficacy towards the neonicotinoid pesticide acetamiprid. The influence of pH (2–10), temperature (20–45 °C), adsorbent dose (0.2–1.2 g L−1), contact time (5–60 min), and initial pesticide concentration (10–60 mg L−1) on the adsorption process of acetamiprid on BC1 was studied. The adsorption capacity of BC1 was 17.8 mg g−1 under optimum conditions (i.e., 20 mg L−1 initial acetamiprid concentration, pH 8, 1 g L−1 adsorbent dose, 25 °C, and 15 min contact time). The equilibrium data obtained from the adsorption experiment fitted well with the Langmuir isotherm model. We developed an effective nanoporous adsorbent for the recycling of crab shells which can be applied on site with minimal laboratory infrastructure according to local needs. [ABSTRACT FROM AUTHOR]

Different microorganisms are present in nature, some of which are assumed to be hazardous to the human body. It is crucial to control their continuing growth to improve human life. Nanomaterial surface functionalization represents a current topic in continuous evolution that supports the development of new materials with multiple applications in biology, medicine, and the environment. This study focused on the antibacterial activity of different nanocomposites based on functionalized multi-walled carbon nanotubes against four common bacterial strains. Two metal oxides (CuO and NiO) and two antibiotics (azithromycin and ciprofloxacin) were selected for the present study to obtain the following nanocomposites: MWCNT-COOH/Antibiotic, MWCNT-COOH/Fe3O4/Antibiotic, and MWCNT-COOH/Fe3O4/MO/Antibiotic. The present study included two Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis) and two Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Ciprofloxacin (Cip) functionalized materials (MWCNT-COOH/Fe3O4/Cip) were most efficient against all tested bacterial strains; therefore, we conclude that Cu and Ni reduce the effects of Cip. The obtained results indicate that the nanocomposites functionalized with Cip are more effective against selected bacteria strains compared to azithromycin (Azi) functionalized nanocomposites. The current work determined the antibacterial activities of different nanocomposites and gave fresh insights into their manufacture for future research regarding environmental depollution. [ABSTRACT FROM AUTHOR]

In this study the adsorption and photodegradation capabilities of modified multi-walled carbon nanotubes (MWCNTs), using tartrazine as a model pollutant, is demonstrated. MWCNT-COOH/Fe3O4 and MWCNT-COOH/Fe3O4/NiO nanocomposites were prepared by precipitation of metal oxides in the presence of MWCNTs. Their properties were examined by X-ray diffraction in powder (XRD), Fourier-transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, synchrotron-based Scanning PhotoElectron Microscopy (SPEM), and Brunauer-Emmett-Teller (BET) analysis. It was found that the optimal adsorption conditions were pH 4 for MWCNT-COOH/Fe3O4 and pH 3 for MWCNT-COOH/Fe3O4/NiO, temperature 25 °C, adsorbent dose 1 g L−1, initial concentration of tartrazine 5 mg L−1 for MWCNT-COOH/Fe3O4 and 10 mg L−1 for MWCNT-COOH/Fe3O4/NiO and contact time 5 min for MWCNT-COOH/Fe3O4/NiO and 15 min for MWCNT-COOH/Fe3O4. Moreover, the predominant degradation process was elucidated simultaneously, with and without simulated sunlight irradiation, using thermal lens spectrometry (TLS) and UV–Vis absorption spectrophotometry. The results indicated the prevalence of the photodegradation mechanism over adsorption from the beginning of the degradation process. [ABSTRACT FROM AUTHOR]

Abiotic stress agents, among them metal stress, can cause oxidative damage to plant cells. In defense, plants can increase the production of secondary metabolites in order to mitigate the harmful effects caused by them. The purpose of this work was to evaluate the effect of two types of copper salts (CuSO4 and Cu(NO3)2), added in two different amounts in soil (150 mg/kg, respectively 300 mg/kg), on assimilating pigments, total polyphenols, antioxidant activity and the elemental composition of wheat. The obtained results were compared with those from control plants grown in the same conditions but without copper salts. The amount of assimilating pigments, total polyphenols, and antioxidant activity respectively increases or decreases in the plants treated with copper salts compared to the control depending on the stage of development of the plant. No significant damage induced in the leaves of the wheat plants treated with the selected salts was observed following the TEM analysis. In six-week-old plants it was observed by EDX analysis that the salts are transformed into nanoparticles. The bioactive compounds, elemental composition and their interaction is influenced by concentration of metal's salt, type of salt and exposure period. [ABSTRACT FROM AUTHOR]

The main goal of this work consists of synthesis of new magnetic multifunctional nanoplatforms based on Fe@FePt core, with principal target in applications regarding the capture and separation of amino acids. These expectations were fulfill by attaching amino functional groups on the core surface. Therefore, our Fe@FePt@SiO2@NH2 core-shell nanoparticles could serve as promising multifunctional nanoplatforms for molecular recognition and magnetic separation. In this way, these nanoplatforms are capable to catch the amino acids (lysine, cysteine, and alanine) from liquid media. The properties of the obtained nanoparticles were evaluated, and the retention level was determined by high-performance liquid chromatography. It was found that for a mass ratio of 10 and 40 between nanoparticles and amino acids, the lysine is best retained from liquid media. For a mass ratio of 20, the best level of retention was realized for alanine. The most responsive was the lysine followed by the alanine and then by the cysteine. [ABSTRACT FROM AUTHOR]

Tri- and diorganotin(IV) pseudohalides of type [2-(Me 2 NCH 2 )C 6 H 4 ]R 2 Sn(NCE) [E = S, R = Me ( 1 ); E = Se, R = Me ( 2 ), Ph ( 3 )] and respectively [2-(Me 2 NCH 2 )C 6 H 4 ]RSn(NCE) 2 [E = S, R = n Bu ( 4 ), Ph ( 5 ), 2-(Me 2 NCH 2 )C 6 H 4 ( 6 ); E = Se; R = 2-(Me 2 NCH 2 )C 6 H 4 ( 7 )] were obtained by reacting the appropriate organotin(IV) chlorides and alkali metal pseudohalides in stoichiometric amounts. The new species were characterized by multinuclear NMR ( 1 H, 13 C, 119 Sn and 77 Se where appropriate), IR spectroscopy and mass spectrometry. Both the 119 Sn NMR and the X-ray diffraction studies evidenced the formation of Sn–NCE bonds in these compounds. For compounds 1 – 4 , 6 and 7 the single-crystal X-ray diffraction studies revealed intramolecular Me 2 N→Sn interactions and the formation of hypervalent species 10- Sn -5 in compounds 1 – 3 and 12- Sn -6 in 4 , 6 and 7 , respectively. Compounds 1 – 3 are monomeric species, with monodentate isochalcogenocyanato ligands, while in 4 one of the NCE − ligands behave as a bridging moiety, thus resulting in dimeric associations. Short π CH γ-CH2 ⋯C g and respectively C g ⋯C g intermolecular contacts resulted in polymeric chains of dimmers in 4 and 3D supramolecular networks in 6 and 7 , respectively. The reactions of [2-(Me 2 NCH 2 )C 6 H 4 ]RSnCl 2 and MECN in an 1:1 molar ratio resulted in the formation of a mixture of [2-(Me 2 NCH 2 )C 6 H 4 ]RSnCl 2 , [2-(Me 2 NCH 2 )C 6 H 4 ]RSn(NCE) 2 and [2-(Me 2 NCH 2 )C 6 H 4 ]RSnCl(NCE) [E = S, R = Ph ( 8 ), 2-(Me 2 NCH 2 )C 6 H 4 ( 9 ); E = Se, R = 2-(Me 2 NCH 2 )C 6 H 4 ( 10 )]. [ABSTRACT FROM AUTHOR]

The present study reports the cymoxanil adsorption efficiency on carboxy-carbon nanotubes (CNT-COOH)/manganese(IV) oxide (MnO2)/iron(II,III) oxide(Fe3O4) nanocomposite. The optimum conditions were determined by studying the influence of pH (2-10), temperature (20-60 °C), initial cymoxanil concentration (7-20 mg L−1), adsorbent dose (0.5-5 g L−1) and contact time (2-30 min) on the adsorption process. The isotherm and kinetic models were used to analyze the experimental data. The Langmuir isotherm model was shown to provide the best fit with a 10.672 mg g−1 maximum adsorption capacity. Also, the cymoxanil adsorption follows the pseudo-second order kinetic model. According to these results, the CNT-COOH/MnO2/Fe3O4 nanocomposite may be used for cymoxanil removal from aqueous solution. [ABSTRACT FROM AUTHOR]

In this paper, the applicability of carboxylic functionalized carbon nanotubes modified with metal oxides of Fe and Mn (CNT-COOH/MnO2/Fe3O4) as adsorbent for the removal of two pesticides from aqueous solution in batch method was studied. The two pesticides studied were devrinol and triadimefon. Their adsorption on nanocomposite was studied in relation to several factors such as the effect of the pH, initial concentration of pollutant, amount of adsorbent dose, temperature and contact time. The residual pesticide concentration was determined using high-performance liquid chromatography coupled with photodiode array detector (HPLC–PDA). The experimental data best fit with Langmuir isotherm model and follow the pseudo-second-order kinetic model. Depending on the temperature, the adsorption capacity of pesticides on nanocomposite varies between 14.925 and 20.492 mg g−1 for devrinol and between 12.723 and 14.706 mg g−1 for triadimefon. The thermodynamic parameters indicated that the retention of devrinol and triadimefon onto CNT-COOH/MnO2/Fe3O4 was spontaneous and endothermic. The experimental results obtained reveal that CNT-COOH/MnO2/Fe3O4 nanocomposite is a promising adsorbent for pesticides removal from the wastewater. [ABSTRACT FROM AUTHOR]

Water contamination is a ubiquitous issue for all countries and territories worldwide. Among others, pesticides, drugs, heavy metals, and phosphates play a special role in terms of pollutants due to their toxicity and large-scale applications in industrial and agricultural activities. In order to provide cleaner freshwater for the world's population, two types of actions are required: preventing/limiting the pollution that might occur during our daily activities and decontaminating the already exposed/contaminated water sources. One of the key points in the decontamination process is to create as few as possible side effects with the solutions applied. For this reason, in the case of the mentioned types of pollutants but not limited only to them, the use of environmentally friendly materials is more than welcome. Biochar qualifies as one of these materials, and its field of applications expands to larger scientific and industrial areas every day. Moreover, it can be functionalized in order to improve its properties in terms of pollutant removal efficiency. This paper summarizes the most recent developments in the field of water decontamination using biochar or biochar-based materials in order to remove pesticides, drugs, heavy metals, and phosphates from contaminated aqueous environments. Also, the removal of phosphorus from wastewater using biochar is considered. This removal can be a key controlling factor for the wastewater, which is obtained as a residual of agricultural activities. Indeed, due to the excessive use of chemical fertilizers, eutrophication in such kinds of wastewater can be a serious challenge. [ABSTRACT FROM AUTHOR]

Plant extracts and essential oils have a wide variety of molecules with potential application in different fields such as medicine, the food industry, and cosmetics. Furthermore, these plant derivatives are widely interested in human and animal health, including potent antitumor, antifungal, anti-inflammatory, and bactericidal activity. Given this diversity, different methodologies were needed to optimize the extraction, purification, and characterization of each class of biomolecules. In addition, these plant products can still be used in the synthesis of nanomaterials to reduce the undesirable effects of conventional synthesis routes based on hazardous/toxic chemical reagents and associate the properties of nanomaterials with those present in extracts and essential oils. Vegetable oils and extracts are chemically complex, and although they are already used in the synthesis of nanomaterials, limited studies have examined which molecules are effectively acting in the synthesis and stabilization of these nanostructures. Similarly, few studies have investigated whether the molecules coating the nanomaterials derived from these extracts and essential oils would bring benefits or somehow reduce their potential activity. This synergistic effect presents a promising field to be further explored. Thus, in this review article, we conducted a comprehensive review addressing the main groups of molecules present in plant extracts and essential oils, their extraction capacity, and available methodologies for their characterization. Moreover, we highlighted the potential of these plant products in the synthesis of different metallic nanomaterials and their antimicrobial capacity. Furthermore, we correlated the extract's role in antimicrobial activity, considering the potential synergy between molecules from the plant product and the different metallic forms associated with nanomaterials. [ABSTRACT FROM AUTHOR]

Heavy metals represent a large category of pollutants. Heavy metals are the focus of researchers around the world, mainly due to their harmful effects on plants. In this paper, the influence of copper, cadmium, manganese, nickel, zinc and lead, present in soil in different concentrations (below the permissible limit, the maximum permissible concentration and a concentration higher than the maximum permissible limit) on lettuce (Lactuca sativa L.) was evaluated. For this purpose, the authors analyzed the variation of photosynthetic pigments, total polyphenols, antioxidant activity and the elemental content in the studied plants. The experimental results showed that the variation of the content of biologically active compounds, elemental content and the antioxidant activity in the plants grown in contaminated soil, compared to the control plants, depends on the type and concentration of the metal added to the soil. The biggest decrease was recorded for plants grown in soil treated with Ni I (−42.38%) for chlorophyll a, Zn II (−32.92%) for chlorophyll b, Ni I (−40.46%) for carotenoids, Pb I (−40.95%) for polyphenols and Cu III (−29.42%) for DPPH. On the other hand, the largest increase regarding the amount of biologically active compounds was registered for Mn I (88.24%) in the case of the chlorophyll a, Mn I (65.56%) for chlorophyll b, Pb I (116.03%) for carotenoids, Ni III (1351.23%) for polyphenols and Ni III (1149.35%) for DPPH. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the sun protection factor (SPF) of cosmetic emulsions with the addition of hydroalcoholic apple extract. First, the total polyphenolic content, the antioxidant activity and SPF properties of the extracts obtained by sonication and refluxing were evaluated. The two extraction methods were improved using the central composite design. For cosmetic emulsion that contained a different concentration of apple extract (10–40%), a SPF value between 0.51 and 0.90 was obtained. The most efficient apple extract was obtained by reflux using 50% ethanol and a 60 min extraction time. The concentrated extract was incorporated in a cosmetic emulsion whose SPF maximum was 0.90. Accordingly, due to photoprotective properties, the apple extract can be a candidate for use in cosmetic formulations. [ABSTRACT FROM AUTHOR]

The aim of this work was to obtain different extracts rich in polyphenols of the blackthorn by reflux and sonication and to test them in sunscreen formulation. In order to obtain the maximum content of polyphenols, a high antioxidant capacity and a high sun protection factor of these extracts, a central composite design was employed to optimize the extraction parameters. The extraction time (30–150 min) and the ethanol concentration (40–80%) were considered for refluxing, and the extraction time (5–30 min), temperature (30–70 °C) and the ethanol concentration (40–80%) were for ultrasound-assisted extraction. The optimal conditions were found to be 30% ethanol concentration and the time 45 min for reflux extraction and the temperature 67 °C, the ethanol concentration 40% and time 10 min for ultrasound-assisted extraction. Due to antioxidant and photo protective properties of the blackthorn extract and its usage in sunscreen formulation, in vitro sun protection factor and photostability of the sunscreen formulation were also determined. Results from this study showed that the blackthorn fruit extract has importance utility in formulation with solar protection properties. [ABSTRACT FROM AUTHOR]

• CNT-COOH/MnO 2 /Fe 3 O 4 nanocomposite prepared is a new adsorbent. • The adsorption process depends on pH, temperature, time, adsorbent dose, drugs concentration. • High adsorption capacity of ibuprofen and paracetamol was obtained on CNT-COOH/MnO 2 /Fe 3 O 4. The nanocomposite CNT-COOH/MnO 2 /Fe 3 O 4 was synthesized and characterized by different techniques, namely X-ray diffraction, Fourier-transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, energy dispersive spectroscopy, thermogravimetric analysis, Brunauer-Emmett-Teller analysis, magnetic measurement, point of zero charge and hydrophobicity index. Analyzes revealed the groups -COOH, MnO 2 and Fe 3 O 4 attached to the carbon nanotubes, the acidic character of the obtained nanocomposite and its stability. The surface area for the obtained nanocomposite was 114.2 m2 g−1. The prepared nanocomposite was used for adsorption of ibuprofen and paracetamol from aqueous solution. Isotherm, kinetic and thermodynamic parameters were determined for predicting the ibuprofen and paracetamol adsorption on synthetized nanocomposite. The equilibrium data obtained from adsorption were well represented by Langmuir model and kinetics data were well fitted by the pseudo-second order model. The maximum adsorption capacity obtained for ibuprofen and paracetamol was 103.093 mg g−1, 80.645 mg g−1 respectively. The thermodynamic analysis showed that the adsorption process for both pollutants was spontaneous and endothermic. The synthetized nanocomposite can be a suitable new absorbent for ibuprofen and paracetamol removal from aqueous solutions due to its high adsorbing capacity and it can be separated by an external magnetic field. [ABSTRACT FROM AUTHOR]

Nanocomposites based on half-metallic FePt (L10) magnetic nanoparticles coated with the semiconducting conjugated polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) show a significant reduction in the magnetic coercivity. This study adopts a physical approach based on chemical potential equalization at the interface. The underlying charge/spin transfer mechanism unveils an imbalance: only spin-down polarized electrons are allowed to be transferred from the semiconductor to the half-metal (spin-down) conduction band, while spin-up states remain blocked at the interface. This process determines an excess of spin-up states on the P3HT side, and due to a RKKY mechanism, this effective spin system becomes ferromagnetic polarized. Due to this proximity effect, the conjugate polymer becomes exchange coupled to the hard magnetic FePt (L10) phase, thus reducing the coercivity of the half-metal. These processes make this type of composite suitable for magnetic recording applications. [ABSTRACT FROM AUTHOR]

The present work aims to follow the influence of TiO2 nanoparticles (TiO2 NPs) on bioactive compounds, the elemental content of wheat, and on wheat leaves' ultrastructure. Synthesized nanoparticles were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and transmission electron microscopy (TEM). The concentration of phenolic compounds, assimilation pigments, antioxidant capacity, elemental content, as well as the ultrastructural changes that may occur in the wheat plants grown in the presence or absence of TiO2 NPs were evaluated. In plants grown in the presence of TiO2 NPs, the amount of assimilating pigments and total polyphenols decreased compared to the control sample, while the antioxidant activity of plants grown in amended soil was higher than those grown in control soil. Following ultrastructural analysis, no significant changes were observed in the leaves of TiO2-treated plants. Application of TiO2 NPs to soil caused a significant reaction of the plant to stress conditions. This was revealed by the increase of antioxidant capacity and the decrease of chlorophyll, total polyphenols, and carotenoids. Besides, the application of TiO2 NPs led to significant positive (K, Zn, Br, and Mo) and negative (Na, Mn, Fe, As, Sr, Sb, and Ba) variation of content. [ABSTRACT FROM AUTHOR]