在离子色谱法测定可口可乐饮料中3种阴离子(PO3-4,SO2-4及NO-3)时,单独用Dionex IonPac AG14A柱代替常规方法中的联合用两柱Dionex IonPac AS14及IonPac AG14作色谱柱.采用5 mmol·L-1 Na2CO3及6 mmol·L-1 NaHCO3的混合溶液作流动相,上述3种阴离子的分离可在3 min内完成.饮料试样在色谱分离之前需经脱气并先后通过Dionex On-guard P及RP两柱以除去“可乐”饲料中可能存在的酚类物质及大分子有机物.对方法的精密度作了试验,3种阴离子的峰面积的RSD(n=6)值均小于0.2%,回收率在90.5%~103.2%之间.

In the rapid ion-chromatographic determination of PO3-4,SO2-4 and NO-3 anions in the drink “Coca Cola”,the combining use of the columns of Dionex IonPac AS14 and IonPac AG14 was substituted by the single used of the IonPac AG14A,as chromatographic column which made the 3 anions separated satisfactorily within 3 min.A mixed solution of 5 mmol·L-1 Na2CO3 and 6 mmol·L-1 NaHCO3 was used as mobile phase.The drink sample,after de-gasing,was passed through columns of Dionex On-Guard P and RP successively to remove those possibly co-existing phenols and macromolecular compounds,before the separation in IonPac AG14A.Precision of the determination was tested,and values of RSD′s (n=6) found for the 3 anions were less than 0.2%.Values of recovery obtained were in the range of 90.5%-103.2%.