Oxidation of As(III) in aqueous solutions by means of macroporous redox copolymers with N-chlorosulfonamide pendant groups

The possibility of oxidizing As(III) to As(V) in aqueous solutions by means of heterogeneous oxidants, i.e. synthetic macromolecular redox compounds, was studied. The materials contain N-chlorosulfonamide functional groups in the sodium form: [P]-SO(2)NClNa (R/ClNa, 2.1 mmol/g) or in the hydrogen form: [P]-SO(2)NClH (R/ClH, 2.4 mmol/g), attached to a cross-linked macroporous poly(styrene-divinylbenzene) matrix. They were obtained through the transformation of Amberlyst 15 (Rohm and Haas) commercial cation exchanger's sulfonic functional groups. The experiments were conducted in the H(2)O and 0.01 M NaOH environment (R/ClNa) and in the H(2)O and 0.01 M H(2)SO(4) environment (R/ClH), using the batch process and the column process and NaAsO(2) solutions (93-375 mg As(III)/dm(3)). The experiments showed that the two copolymers' capacity to oxidize As(III) is high and depends on the process conditions. In the column process experiments, conducted using NaAsO(2) solutions with a concentration of ～ 93 mg As(III)/dm(3) at a flow rate of 4 BV/h (R/ClH) and 6 BV/h (R/ClNa), a breakthrough (defined as the exceedance of 0.05 mg As(III)/dm(3) in the effluent) would occur after the solutions amounting to about 400 bed volumes had been passed through the column.     

Sorption of zinc by novel pH-sensitive hydrogels based on chitosan, itaconic acid and methacrylic acid

Novel pH-sensitive hydrogels based on chitosan, itaconic acid and methacrylic acid were applied as adsorbents for the removal of Zn²⁺ ions from aqueous solution. In batch tests, the influence of solution pH, contact time, initial metal ion concentration and temperature was examined. The sorption was found pH dependent, pH 5.5 being the optimum value. The adsorption process was well described by the pseudo-second order kinetic. The hydrogels were characterized by spectral (Fourier transform infrared—FTIR) and structural (SEM/EDX and atomic force microscopy—AFM) analyses. The surface topography changes were observed by atomic force microscopy, while the changes in surface composition were detected using phase imaging AFM. The negative values of free energy and enthalpy indicated that the adsorption is spontaneous and exothermic one. The best fitting isotherms were Langmuir and Redlich-Peterson and it was found that both linear and nonlinear methods were appropriate for obtaining the isotherm parameters. However, the increase of temperature leads to higher adsorption capacity, since swelling degree increased with temperature.     

Porous chitosan/ZnO-doped bioglass composites as carriers of bioactive peptides

In this study, we aimed to assess whether the composite of chitosan/ZnO-doped bioglass can be applied as a suitable scaffold for the incorporation of bioactive peptides. Material of a porous composite with 1:1 ratio of bioglass:polymer was produced and used as a matrix for delivery of peptide. A peptide with the PEPTIDES sequence (Pro-Glu-Pro-Thr-Ile-Asp-Glu-Ser) was chosen as a model peptide. Microstructure and pore sizes of chitosan/ZnO-doped bioglass were assessed. Open porosity and pore sizes of the composite were suitable for enabling the migration of cells and ensuring the easy delivery of nutrients within the implant. In addition, composite showed bioactivity and bactericidal activity against Staphylococcus aureus and Pseudomonas aeruginosa strains. Peptide alone did not have any cytotoxic activity on human fibroblasts and keratinocytes. Also it did not show any antibacterial properties and did not cause hemolysis of red blood cells. The peptide incorporated in composite showed a rapid release in the kinetics profile. The obtained results indicate that there is the technological possibility to incorporate peptides in chitosan/ZnO-doped bioglass scaffolds. Such biomaterials have potential application in bone tissue engineering.     

Particle swarm intelligence tunning of fuzzy geometric protoforms for price patterns recognition and stock trading

A novel approach for detecting patterns in price time series is shown. The proposed system for identifying consolidation phases is based on fuzzy geometric protoforms and classification trees. Promising results of the empirical studies prove that the suggested fuzzy geometric protoforms are very useful for identifying patterns in graphical visualizations of data. Moreover, the architecture of the system enables successful incorporation of genetic optimization what enables capturing various data sets structure and unstable conditions on financial markets.     

Diet with linseed oil and organic selenium yields low n‐6/n‐3 ratio pork Semimembranosus meat with unchanged volatile compound profiles

The aim of this was to improve n‐6/n‐3 ratio without affecting the volatile compounds profiles of pork. Different feeding strategies were designed for 60 Polish Landrace pigs with the goal to enhance the health attributes of Polish pork. Composition, colour, hardness, fatty acid contents and volatile compound profiles of the semimembranosus muscles were determined. Results showed that with the basic diet with the addition 3% of linseed oil, 100 mg kg^?1 of vitamin E and 1 mg kg^?1 of organic selenium, the level of polyunsaturated fatty acids (PUFA) in the meat samples was increased by 26% (P ≤ 0.05) as compared to the control. Principal component analysis (PCA) demonstrated that the aroma profile of semimembranosus muscles from pigs fed with the diet supplemented with 3% of linseed oil and 1 mg kg^?1 of organic selenium was close to that of control. Results demonstrated that healthy functional meats could be produced by designing feeding strategies.     

Determination of the botanical origin of honeybee honeys based on the analysis of their selected physicochemical parameters coupled with chemometric assays

Food Science and Biotechnology - The aim of this paper was to study the select physicochemical parameters of 58 honey samples of 4 different botanical origins (buckwheat, linden, rape and acacia)...     

Bacterial nanocelullose in biomedical applications: a review

This review reports recent advances in the application of bacterial nanocellulose (BNC) in biomedical fields. BNC has attracted both academic and industrial attention as it shows interesting properties for both biomedical and cosmetic applications. Herein, the structure, properties and selected applications of BNC in the preparation of wound dressings and artificial skin are discussed in general, and detailed examples are also drawn from the scientific literature. In this review the most common applications are presented in detail together with issues related to regenerative medicine and biomedicine, skin tissue engineering, auricular cartilage reconstruction, bone regeneration and the treatment of traumatic tympanic membrane perforation. © 2019 Society of Chemical Industry     

Synthesis and characterization of ceramic - polymer composites containing bioactive synthetic hydroxyapatite for biomedical applications

Presented research involved preparation of hydroxyapatite and synthesis of composites based on gelatin, albumin and polyvinylpyrrolidone (PVP) modified with the obtained compound. Hydroxyapatite was attained as a product of two-stage processing of pig bones. Applied procedure involved hydrolysis of the raw material in acidic environment and double calcination. Molar ratio Ca/P of hydroxyapatite has been determined and its chemical structure has been characterized using X-ray diffraction and FT-IR spectroscopy. Ratio Ca/P calculated on the basis of conducted research was 1.50?±?0.05. Thus prepared material met the ISO requirements, which assume that the Ca/P ratio should be in the range 1.5–2.0, which qualifies the material for further studies. Next, series of polymer matrix on the basis of gelatin, albumin and polyvinylpyrrolidone (PVP) has been synthesized and subjected to some analyzes. On the basis of the conducted studies, matrixes with the most favorable features such as desirable strength, flexibility and crosslinking degree were modified with previously prepared hydroxyapatite. Surface morphology and elemental composition of the composites have been analyzed using SEM-EDS method. Additionally, sorption capacity of modified composites and their behavior in simulated body fluids have been determined. Based on the conducted research it can be concluded that pig bones represent a good material for preparation of hydroxyapatite. Furthermore, composites based on proteins of natural origin modified with attained hydroxyapatite constitute a promising material that can be used for biomedical purposes.     

Micro-cantilevers for optical sensing of biogenic amines

Microsystem Technologies - This paper discusses the functionalization of micro-cantilevers in order to bind and sense specific biogenic amines related to meat degradation (cadaverine). The...