离子色谱法检测牙膏粉中的甘油磷酸及其它离子

Simple, reliable and sensitive analytical methods to determine the anions, such as fluoride, monofluorophaosphate, glycerophosphate related to
anticaries are necessary for basic investigations of anticaries and quality control of dentifrices. A method for the simultaneous determination of
organic acids, organic anions and inorganic anions in the sample of commercial toothpaste is proposed. Nine anions (fluoride, chloride, nitrite,
nitrate, sulfate, phosphate, monofluorophaosphate, glycerophosphate and oxalic acid) were analyzed by means of ion chromatography using a
gradient elution with KOH as mobile phase, IonPac AS18 as the separation column and suppressed conductivity detection. Optimized analytical
conditions were further validated in terms of accuracy, precision and total uncertainty and the results showed the reliability of the IC method. The
relative standard deviations (RSD) of the retention time and peak area of all species were less than 0.170 and 1.800%, respectively. The correlation
coefficients for target analytes ranged from 0.9985 to 0.9996. The detection limit (signal to noise ratio of 3:1) of this method was at low ppb level
(<15 ppb). The spiked recoveries for the anions were 96103%. The method was applied to toothpaste without interferences.