ABSTRACT:The sorption of cadmium and humic acids from aqueous solutions using surface-modified nanozeolite A has been investigated under various examination conditions. The morphology of untreated and treated nanozeolite was studied under scanning electron microscope and transmission electron microscope. Isotherms of cadmium adsorption onto surfacemodified nanozeolite A were studied at different pH, solid to liquid ratio, adsorbate concentration and interaction time. Kinetic and equilibrium studies were conducted and the equilibrium data have been analyzed using Langmuir and Freundlich isotherm models. The study revealed that experimental results were in agreement with the Freundlich model. The Langmuir monolayer adsorption capacity was found to be 1666.67 g cadmium and 6.75 g humic acid per gram of modified nanozeolite A, which is higher than that of reported value for other zeolites. The sorption ability was enhanced by surface modification and reduction in size and enabled the zeolite to adsorb cadmium. The adsorption of cadmium and humic acid on nanozeolite was found to be the highest at pH 6 and 3, respectively. Results showed that solid to liquid ratio and pH are the most important factors for cadmium and humic acid removal, respectively. Effect of competitive ions was studied and results showed that there is no competition between cadmium and humic acid sorption and presence of these ions.

Diazinon, a commonly used organophosphorus pesticide, has been widely used throughout the world in agriculture and horticulture to control insects that feed on crops, ornamentals, lawns, fruits, vegetables and other food products. The toxicity of the DZN causes adverse effects on many organs. The purpose of this study was to examine the protective effect of vitamins A, E and C on liver enzymes alanine transaminase (ALT), Aspartate aminotransferase (AST) and Lactate Dehydrogenase (LDH) in rats exposed to diazinon. In this study, male wistar rats were randomly divided into 10 different groups. The groups were administered normal saline, soybean oil (as the solvent for diazinon and fat-soluble vitamins), diazinon, (30 mg kg(-1), vitamins E, C and A (100, 500 mg kg(-1) and 400 IU kg(-1), respectively) and a combination of diazinon with the same dose of each vitamin intraperitoneally i.p.daily for 14 days. Seven days after the final injection, the animals were anesthetized and blood samples were taken. The photometric method was used to measure the activity of the enzymes. The activities of ALT and AST in the diazinon group were significantly higher than that observed in the control group; however, the diazinon/vitamin E, A, C group displayed significant reduction in ALT and AST activities compared to the diazinon group. The lowest level of LDH enzyme activity was observed in the dazinon/vitamin C group and this was statistically lower than the diazinon group. The results of this study revealed that vitamin E, A and C have a potent protective effect against diazinon-induced hepatotoxicity in rats, which may be due to the scavenging of free radicals and increased antioxidant status.

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Octreotide as a synthetic cyclic octapeptide is a somatostatin analog with longer half-life and more selectivity for inhibition of the growth hormone. The acetate salt of octreotide is currently used for medical treatment of somatostatin-related disorders such as endocrine and carcinoid tumors, acromegaly, and gigantism. Octreotide contains both cysteine and tryptophan residues which make the hydrolysis part of its amino acid analysis procedure very challenging. The current paper introduces a fast and additive-free method which preserves tryptophan and cysteine residues during the hydrolysis. Using only 6 M HCl, this hydrolysis process is completed in 30 min at 150 °C. This fast hydrolysis method followed by pre-column derivatization of the released amino acids with 4-N,N-dimethylaminoazobenzene-4'-sulfonyl chloride (DABS-Cl) which takes only 20 min, makes it possible to do the complete amino acid analysis of an octreotide sample in a few hours. The highly stable-colored DABS-Cl derivatives can be detected in 436 nm in a reversed phase chromatographic system, which eliminates spectral interferences to a great extent. The amino acid analysis of octreotide acetate including hydrolysis, derivatization, and reversed phase HPLC determination was validated according to International Conference of Harmonization (ICH) guidelines.

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