background & aim: according to the increase in diseases such as diabetes and obesity, using of saccharose alternatives for producing of low-calorie and sugar-free alternatives, are taken into consideration of researchers and industrialists. among them, steviosidewith the 300 times more sweetness than saccharose has special place, due to is a natural. the aim of this study is optimizing of stevi...

this study a novel high performance liquid chromatography for the assay of nystatin in oral and vaginal tablets were optimized and validated using box–behnken experimental design. the method was performed in the isocratic mode on a rp-18 column (30 °c) using a mobile phase consisting of 0.05 m ammonium acetate buffer/ methanol mixture (30:70) and a flow-rate of 1.0 ml/min. the method was valida...

purpose : fluoroquinolones are widely used antibiotic for prophylaxis of intra and postoperative infections in individuals undergoing cataract surgery. this study was designed to assess the penetration of ciprofloxacin into the ocular aqueous humor (topical only versus topical and oral administration). methods : studied population (n=47) consisted of two groups: group one (n=26) and group two (...

Surfactants are widely used in household and industrial products. The risk of incorporation of linear alkylbenzene sulfonates (LAS) from biosolids, wastewater, and fertilizers land application to the food chain is being assessed at present by the European Union. In the present work, a complete analytical method for LAS trace determination has been developed and successfully applied to LAS (C10-...

The occurrence and levels of benzo[a]pyrene in various heat-treated foods from China were evaluated by high-performance liquid chromatography-fluorescence detection. In a total of 119 samples, 105 were found to contain benzo[a]pyrene at levels of 0.03 to 19.75 μg/kg. The benzo[a]pyrene contents in 12 animal source foods were higher than the Chinese maximum permissible level in food (5 μg/kg) an...

This work describes the application of ultrasound-assisted matrix solid-phase dispersion as an extraction and sample preparation approach for aflatoxins (B1, B2, G1 and G2) and subsequent determination of them by high-performance liquid chromatography-fluorescence detection. A Box-Behnken design in combination with response surface methodology was used to determine the affecting parameters on t...

Background: Astaxanthin is widely and naturally distributed in marine animals including, crustaceans, such as shrimp, crabs, and fish, such as salmon and trout. Methods: A total of 20 trout samples were collected from local market and were analyzed for astaxanthin via HPLC-UV. Analyte extraction was done by water, methanol, dichloromethane, and acetonitrile 4.5:85:5:45.5, v/v/v/v. Results: Desp...

background and objectives: furfural (f) and hydroxymethyl furfural (hmf) are cyclic aldehydes, which are formed during the heat processing of foods. these chemical contaminants have received much attention due to their suspected health hazards and heat damage indicators. the aim of the present study was extraction and determination of f and hmf in baby-foods using dispersive liquid-liquid micro...

objective(s) a sensitive liquid chromatographic method for the analysis of clarithromycin- a macrolide antibiotic- in human serum, using pre-column derivatization with 9-fluorenylmethyl chloroformate (fmoc-cl) is described. materials and methods the method involved liquid-liquid extraction of the drug and an internal standard (amantadine) followed by pre-column derivatization of the analytes wi...

5-hydroxymethylfurfural (5-hmf) is known as an indicator of quality deterioration in a wide range of foods. the current study covered 70 samples taken from domestically produced foods and drinks available on the iranian markets (including honey, jam, fruit cakes tomato paste, ketchup, syrup, fruit juice, canned fruit, uht milk, instant coffee and jelly powder). hmf levels were determined using ...