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Beverages or mineral water ions, preservatives, sweeteners, iodine analysis methods are many, AAS, UV-visible spectroscopy, fluorescence spectroscopy, enzymatic, gas chromatography and high performance liquid chromatography. In recent years, the rapid development of ion chromatography technology, a breakthrough in hardware is \. This paper attempts to exploit this latest development reagent-free ion chromatography techniques routinely used in beverages and mineral water analyte determination to establish a continuous, rapid, simple and accurate analytical method. Conclusions are as follows: 1, using eluent generator, IonPac CS16 cation exchange column, ion suppressed conductivity detection simultaneous determination of the seven kinds of mineral cations Li , Na , NH 4 , K , Mg 2 , Ca 2 , Sr 2 content. Seven kinds of cations between the minimum detection limits 0.2μg/L-1.1μg/L, the correlation coefficient of linear equations are greater than 0.9943, a good linear relationship, peak area and peak height RSD (n = 8), respectively 2.31% and 2.01% or less, and the spiked recoveries between 94.0% -103.1%; studied the suppression condition and cation trap column on the determination of the impact; fixed eluent concentration, changing suppressor current, the size of the one found in the current price cations has little effect on peak shape and response, while a greater impact on divalent cations, 40mA current inhibition relative standard deviation obtained minimum and maximum peak response; experiments show that cation trap column can effectively reduce the background conductivity and baseline drift, improve the measurement re- now sex; addition, cation inhibition mechanism was discussed, derived cationic conductance and suppression of current intensity response relationship, seen from the relationship, under certain conditions, inhibition of the peak current will directly affect the response. 2, the establishment of eluent generator conductance suppressed ion chromatography method of bromate in drinking. The method uses a high-capacity anion column for the separation column IonPacAS11HC automatically eluent pure KOH eluent generator, some organic matter samples were removed and chloride ions, can be directly analyzed. The linear range, high sensitivity, good reproducibility relative standard deviation (RSD) sample was 2.09% -3.94%, the average recovery of 97.8% -104.8% and the detection limit was 0.2μg/kg. 3, first established for the analysis to Ionpac-AS11 column, gradient elution ion chromatography reagent free suppressed conductivity detection beverage additives commonly used method, both quickly and efficiently in common to both detection of drink four kinds of preservatives and sweeteners : benzoic acid, sorbic acid, A Siba sweet, sodium cyclamate, acesulfame and saccharin. Not only low background conductivity was measured with high sensitivity and without the impact of UV absorption samples, experimental operation is simple; six kinds of additives in 0.035mg/L-1.35mg/L between the detection limit, the linear correlation coefficients were greater than 0.998, the peak area RSD (n = 8) were small 1.64%, and the spiked recoveries of 97.2% -102.5%, respectively. 4, the establishment of a reagent-free beverages iodide ion chromatography pulsed amperometric detection method for integration. Beverage samples were diluted to remove molecular weight greater than 10,000 substances after direct injection analysis, determination of the relative standard deviation RSD (n = 8) 2.41% -3.62%, the sample average recovery in 91.8% -102.6%, and inspection the limit was 0.1μg / L, method is simple and fast.
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