A new sensitive method using high performance liquid chromatography (HPLC) and liquid extraction for the analysis of acrylamide (AA) in potato chips is reported. The method comprises extraction with acetone using ultrasonic bath and reversed phase C18-AQ (2 × 250 mm) column with water as eluent. Flow rate was 0.15 ml min -1 and the column temperature was kept constant at 40 °C. The analysis was performed using a 20 μl injection loop and a UV detector adjusted at 202 nm. In this condition, the retention time for AA was 8 min. A linear calibration curve (regression coefficient = 0.999) in the range of 20-400 ng g -1 was used for quantitative purposes. Limit of detection (LOD) (signal-to-noise ratio of 3:1) and limit of quantification (LOQ) (signal-to-noise ratio of 10:1) for the method was 2.46 and 3.14 ng g -1 , respectively. Extracted samples and standard solutions with different concentrations of AA were analyzed repeatedly in one day and different days to estimate the repeatability and reproducibility of the method. Analysis of variance on the obtained data showed no significant difference between variances in different days. Using the proposed method, different potato chips samples were analyzed in different days in another laboratory. Paired t-test showed no significant difference between the obtained results from the two laboratories.

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Square-wave voltammetry is a fast technique used for determination of trace amounts of acrylamide. When cobalt(II) ions were added to the acrylamide solution, a catalytic peak at about À1.35 V vs. Ag=AgCl was observed, which was proportional to acrylamide concentration. The calibration curve showed good linearity in the range of 200-800 ng mL À1 of acrylamide with a regression coefficient of 0.9989. The limit of detection of the method was 3.52 ng mL À1 , and the relative standard deviations for concentrations of 300 ng mL À1 and 700 ng mL À1 were 99.8% Â 10 À2 and 79.7% Â 10 À2 , respectively.

BACKGROUND: This study introduces a method for simultaneous removal of 2-mercaptobenzoxazole (2MBO) and 2mercaptobenzothiazole (2MBT) from water samples. The method uses a cartridge loaded with copper oxide nanoparticles as an efficient adsorbent to separate these hazardous mercaptans from aqueous solutions in a flow process. RESULTS:The effects of some important parameters such as amounts of adsorbent, pH, buffer type and its volume, electrolyte concentration, contact time, flow rate, tolerable volume of solution, reusability of cartridges and interfering ions on removal efficiency were studied. Data on adsorption were analyzed using linear and non-linear forms of first-and second-order kinetic equations and also Langmuir and Freundlich isotherm models and results showed that maximum adsorption amounts of 90.9 mg g −1 and 158.7 mg g −1 , were obtained for 2MBO and 2MBT, respectively. CONCLUSION: The proposed removal method is independent of pH level of the sample solution and is effective over a wide range of pH values. Using a copper oxide nanoparticle loaded cartridge (CONLC) has the advantage that there is no need to collect nanoparticles after the removal process and that CONLC can be reused for further removal processes (at least three times). This method was successfully applied to remove 2MBT (≥95% removal) from the cooling water of a 3000 MW power plant.

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