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Nowadays, drug delivery has an important role in medical therapy. The use of biopolymers in developing drug delivery systems (DDSs) is increasingly attracting attention due to their remarkable and numerous advantages, in contrast to conventional polymers. Biopolymers have many advantages (biodegradability, biocompatibility, renewability, affordability, and availability), which are extremely important for developing materials with applications in the biomedical field. Additionally, biopolymers are appropriate when they improve functioning and have a number of positive effects on human life. Therefore, this review presents the most used biopolymers for biomedical applications, especially in drug delivery. In addition, by combining different biopolymers DDSs with tailored functional properties (e.g., physical properties, biodegradability) can be developed. This review summarizes and provides data on the progress of research on biopolymers (chitosan, alginate, starch, cellulose, albumin, silk fibroin, collagen, and gelatin) used in DDSs, their preparation, and mechanism of action. [ABSTRACT FROM AUTHOR]

Biochar gained attention due to its definite physico-chemical characteristics and because it is a cost-effective and efficient adsorbent. In this paper, commercial biochar was tested for the removal of tartrazine from aqueous solutions. Thus, the optimum experimental conditions were determined for several parameters (pH, temperature, initial concentration of tartrazine, biochar dose, and contact time). The concentration of tartrazine residues was determined using UV-Vis spectrophotometry. The best experimental results were obtained at 1 mg L−1 concentration of tartrazine, pH 2, 30 °C, 18 min, and 0.9 g L−1 adsorbent dose. The maximum removal efficiency of tartrazine obtained in optimum conditions was 90.18%. The experimental data were analyzed by the isotherm and kinetic models. The isotherm and kinetics of tartrazine removal on biochar follow the Langmuir isotherm and pseudo-second-order kinetics, respectively. According to the Langmuir isotherm model, the biochar showed a maximum adsorption capacity of 3.28 mg g−1. In addition, biochar demonstrated a good reuse potential and therefore can be used for the removal of tartrazine from aqueous solutions. [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]

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]

The aim of this paper consisted of the carbon nanotube nanocomposite testing for the removal of ampicillin from aqueous solutions. To determine the optimum experimental conditions for ampicillin adsorption on nanocomposite, several parameters were selected: the pH, initial concentration of pollutant, adsorbent dose and contact time. The highperformance liquid chromatography was used to determine the residual ampicillin concentration from aqueous solutions. The best removal of the antibiotic on the tested nanocomposite was obtained with an initial concentration of 40 mg L−1 with 1 g L−1, pH 2 in 20 min. [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]

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]

Salt metathesis reactions between K[{SP(OEt)2}(O2SC6H4Cl-4)N] and the copper(I) species CuCl and (Ph3P)2CuNO3, respectively, resulted in the new complexes [Cu({SP(OEt)2}(O2SC6H4Cl-4)N)] (1) and [Cu(PPh3)2({SP(OEt)2}(O2SC6H4Cl-4)N)] (2). The two compounds were characterized by multinuclear NMR (1H, 13C, 31P). Single-crystal X-ray diffraction studies revealed a monomeric structure with a bidentate, monometallic biconnective behavior of the organophosphorus(V) ligand in case of compound 2. For compound 1 the NMR spectra suggest intermolecular associations in solution. [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]

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]

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 m 2  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., (Copyright © 2020 Elsevier B.V. All rights reserved.)