Amine Modified Magnetic Diatomite Particles as an Effcicent Adsorbent for Pecticide Removal

Pesticides are one of the most critical emerging contaminants which are highly toxic for the environment and have potential risk to human health. In this study, surface-modified magnetic diatomite particles (m-DE-APTES) have been suc-cessfully synthesized and used as a sorbent for the removal of endosulfan from an aqueous solution. Magnetic diatomite particles with surface modification were characterized by Fourier transform-infrared spectroscopy (FT-IR), scan-ning electron microscopy (SEM), energy dispersive X-ray (EDX), electron spin resonance (ESR), and surface area measurements. Characterization results sug-gest that magnetic diatomite has a high surface area and porous structure. In addition, m-DE-APTES has higher adsorption capacity (97.2 mg/g) for en-dosulfan pesticide than unmodified diatomite particles (DE) (16.6 mg/g). The adsorption data fit the Langmuir model (R2=0.9905), and the adsorption process took place spontaneously with the values of ΔGo as -2.576. In conclusion, the surface-modified diatomite particles are promising alternative adsorbents for pesticide removal from aqueous solutions.

Amine Modified Magnetic Diatomite Particles as an Effcicent Adsorbent for Pecticide Removal

Pesticides are one of the most critical emerging contaminants which are highly toxic for the environment and have potential risk to human health. In this study, surface-modified magnetic diatomite particles (m-DE-APTES) have been suc-cessfully synthesized and used as a sorbent for the removal of endosulfan from an aqueous solution. Magnetic diatomite particles with surface modification were characterized by Fourier transform-infrared spectroscopy (FT-IR), scan-ning electron microscopy (SEM), energy dispersive X-ray (EDX), electron spin resonance (ESR), and surface area measurements. Characterization results sug-gest that magnetic diatomite has a high surface area and porous structure. In addition, m-DE-APTES has higher adsorption capacity (97.2 mg/g) for en-dosulfan pesticide than unmodified diatomite particles (DE) (16.6 mg/g). The adsorption data fit the Langmuir model (R2=0.9905), and the adsorption process took place spontaneously with the values of ΔGo as -2.576. In conclusion, the surface-modified diatomite particles are promising alternative adsorbents for pesticide removal from aqueous solutions.

Anticoagulant Glycosaminoglycans Activate Respiratory Burst in Neutrophils and Monocytes

Using four different glycosaminoglycans (un fractionated heparin, low-molecular-weight heparin, pen tosan polysulfate, lactobionic acid) and the polypeptide hirudin, we investigated the influence of these anticoag ulant substances on both polymorphonuclear neutrophils and monocytes respiratory burst in vitro. Using real-time analysis, we demonstrated that both unfractionated and low-molecular-weight heparins, as well as pentosan polysulfate, trigger the respiratory burst in neutrophils and monocytes within 3 to 5 s at clinically relevant con centrations. These effects could be antagonized by pre- incubating the anticoagulant drugs with protamine. Scan ning electron microscopy confirmed an activated neutro phil phenotype after exposure to the anticoagulant compounds. Furthermore, we demonstrated that neither increased intracellular Ca2+ levels nor tyrosine phos phorylation of proteins, both mechanisms commonly in volved in the signal transduction in neutrophils, partici pate in the glycosaminoglycan-mediated activation of the respiratory burst. Our results indicate that defined anti coagulant substances can trigger the respiratory burst in vitro, which might also have clinical implications in cer tain diseases. Key Words: Glycosaminoglycans— Hirudin—Polymorphonuclear leukocytes—Monocytes— Respiratory burst—Flow cytometry.