Investigation of the antimicrobial activity and hematological pattern of nano-chitosan and its nano-copper composite.

Novel synthesized Chitosan-Copper oxide nanocomposite (Cs-CuO) was prepared using pomegranate peels extract as green precipitating agents to improve the biological activity of Cs-NP's, which was synthesized through the ionic gelation method. The characterization of biogenic nanoparticles Cs-NP's and Cs-CuO-NP's was investigated structurally, morphologically to determine all the significant characters of those nanoparticles. Antimicrobial activity was tested for both Cs-NP's and Cs-CuO-NP's via minimum inhibition concentration and zone analysis against fungus, gram-positive and gram-negative. The antimicrobial test results showed high sensitivity of Cs-CuO-NP's to all microorganisms tested in a concentration less than 20,000 mg/L, while the sensitivity of Cs-NP's against all microorganisms under the test started from a concentration of 20,000-40,000 mg/L except for the C. albicans species. The hematological activity was also tested via measuring the RBCs, platelet count, and clotting time against healthy, diabetic, and hypercholesteremia blood samples. The measurement showed a decrease in RBCs and platelet count by adding Cs-NP's or Cs-CuO-NP's to the three blood samples. Cs-NP's success in decreasing the clotting time for healthy and diabetic blood acting as a procoagulant agent while adding biogenic CuO-NP's to Cs-NP's increased clotting time considering as an anti-coagulant agent for hypercholesteremia blood samples.

Immobilization of chitosan nanolayers on the surface of nano-titanium oxide as a novel nanocomposite for efficient removal of La(III) from water.

A novel nanocomposite has been designed and synthesized via surface crosslinking of chitosan nanolayers (NChit) with titanium oxide nanoparticles (NTiO2) using glutaraldehyde (Glu) as the crosslinking agent. A simple and green surface chemical reaction was accomplished by the aid of microwave heating process to enforce surface encapsulation and functionalization for the production of the aimed NTiO2-Glu-NChit nanocomposite. The average particles size of nanocomposite was characterized in the range of 52-58nm using SEM and confirmed by the HR-TEM. The XRD, TGA and FTIR were also employed to assure the immobilization and crosslinking processes. NTiO2-Glu-NChit was studied to estimate the sorption efficiency towards La(III) from aqueous solution by the batch technique under different experimental controlling physicochemical parameters such as, initial pH of metal ion solution, contact time, nanocomposite dosage and initial metal ion concentration. The optimum sorption condition for La(III) as the target metal ion was identified at pH=1.0, 3.0 and 6.0. The adsorption process of La(III) was characterized to follow the postulates of Langmuir and Freundlich isotherm models and the adsorption mechanisms were identified to obey the pseudo-second order kinetic model based on the best compatible results with the experimental data.

Magnetically active biosorbent for chromium species removal from aqueous media.

A magnetically active composite as adsorbent was synthesized via a facile in situ one-pot impregnation of magnetic nano-iron oxide (Fe3O4) on the surface of activated carbon (AC) for the formation of AC-Fe3O4. Baker(')s yeast was physically loaded on the resultant adsorbent AC-Fe3O4 to form a novel yeast coated magnetic composite AC-Fe3O4-Yst as biosorbent. The two synthesized adsorbents were characterized by using a scanning electron microscope (SEM) and assessed using Langmuir, the Brunauer-Emmet-Teller (BET) and Dubinin-Radushkevich (D-R) isotherm models. The validity and applicability of these two sorbents in adsorptive removal of chromium species, Cr(VI) and Cr(III), from aqueous solutions under the effect of a magnetic field were studied and evaluated in the presence of various controlling parameters in order to identify the optimal pH, contact time, mass dose and chromium concentrations for such adsorption process. Also, single and multi-stage micro-column techniques were used to study the potential applications of AC-Fe3O4 as magnetically active adsorbents and AC-Fe3O4-Yst as magnetically active biosorbents, for the removal of chromium species from various real water samples.

Enhanced removal of lead by chemically and biologically treated carbonaceous materials.

Hybrid sorbents and biosorbents were synthesized via chemical and biological treatment of active carbon by simple and direct redox reaction followed by surface loading of baker's yeast. Surface functionality and morphology of chemically and biologically modified sorbents and biosorbents were studied by Fourier Transform Infrared analysis and scanning electron microscope imaging. Hybrid carbonaceous sorbents and biosorbents were characterized by excellent efficiency and superiority toward lead(II) sorption compared to blank active carbon providing a maximum sorption capacity of lead(II) ion as 500 µmol g(-1). Sorption processes of lead(II) by these hybrid materials were investigated under the influence of several controlling parameters such as pH, contact time, mass of sorbent and biosorbent, lead(II) concentration, and foreign ions. Lead(II) sorption mechanisms were found to obey the Langmuir and BET isotherm models. The potential applications of chemically and biologically modified-active carbonaceous materials for removal and extraction of lead from real water matrices were also studied via a double-stage microcolumn technique. The results of this study were found to denote to superior recovery values of lead (95.0-99.0 ± 3.0-5.0%) by various carbonaceous-modified-bakers yeast biosorbents.

Chemically and biologically modified activated carbon sorbents for the removal of lead ions from aqueous media.

A method is described for hybridization of the adsorption and biosorption characteristics of chemically treated commercial activated carbon and baker's yeast, respectively, for the formation of environmental friendly multifunctional sorbents. Activated carbon was loaded with baker's yeast after acid-base treatment. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) Spectroscopy were used to characterize these sorbents. Moreover, the sorption capabilities for lead (II) ions were evaluated. A value of 90 µmol g(-1) was identified as the maximum sorption capacity of activated carbon. Acid-base treatment of activated carbon was found to double the sorption capacity (140-180 µmol g(-1)). Immobilization of baker's yeast on the surface of activated carbon sorbents was found to further improve the sorption capacity efficiency of lead to 360, 510 and 560 µmol g(-1), respectively. Several important factors such as pH, contact time, sorbent dose, lead concentration and interfering ions were examined. Lead sorption process was studied and evaluated by several adsorption isotherms and found to follow the Langmuir and BET models. The potential applications of various chemically and biologically modified sorbents and biosorbents for removal of lead from real water matrices were also investigated via multistage micro-column technique and the results referred to excellent recovery values of lead (95.0-99.0 ± 3.0-5.0 %).

Speciation, selective extraction and preconcentration of chromium ions via alumina-functionalized-isatin-thiosemicarbazone.

A method is presented and described for speciation, extraction and preconcentration of Cr(III) and Cr(VI) based on dynamic and static solid phase extraction techniques. Three newly designed alumina phases-physically adsorbed-isatin-thiosemicarbazone (I-III) were synthesized, characterized, tested for stability and applied as inorganic ion exchangers and chelating solid sorbents for various metal ions. The selectivity characteristics incorporated into these alumina phases were studied and evaluated via determination of the distribution coefficients and separation factors of chromium species versus other interacting metal ions. Quantitative recovery of Cr(VI) was accomplished by alumina phases (I-III) in pH 1.0 giving percentage extraction values of approximately 99.9-100.0%, while Cr(III) was found to be quantitatively recovered by these sorbents in pH 7.0 leading to percentage extraction values approximately 100.0% with minimal or no interference between these two species under the studied buffering conditions. Selective solid phase speciation and preconcentration of Cr(III) and Cr(VI) in various real water samples were successfully performed and accomplished by newly designed alumina phases (I-III) via a preconcentration micro-column.