离子色谱法测定一次性筷子中二氧化硫的含量

Determination of sulfur dioxide in disposable chopsticks by ion chromatography

目的：建立一次性筷子中二氧化硫的离子色谱测定方法。方法：用0．05％甲醛热缓冲液浸泡样品，4h后浸泡完全，用0．22μm滤膜过滤后离子色谱法直接测定SO3^2-。结果：浸泡液中SO3^2-在3d内稳定性好，二氧化硫浓度在0～23．00mg／L范围内方法的线性关系良好（r=0．9995），方法的检出限为0．59mg／kg，相对标准偏差在1．33％～2．05％之间，回收率在92％-105％之间，与国标法比较两者无显著性差异。结论：离子色谱法快速、灵敏、准确、选择性高，适用于一次性筷子中二氧化硫的测定。

Objective： To establish a method for determination of sulfur dioxide in disposable chopsticks by ion chromatography. Methods：After immersed with 0.05% formaldehyde buffer solution （100℃） for 4 hours and filtrated with 0.22 μm menbrane,the samples were injected and analyzed. Results： Sulfite was stabilized in 3 days by adding formaldehyde into samples. The method had good linearity（r=0.9995） for the concentration of sulfur dioxide ranged from 0 to 23.00 mg/L. The rates of recovery were between the range of 92% -105%, with the detection limit of 0.59 mg/kg, and the RSD between 1.33% 2.05%. There was no significant difference between the results by this method and those by the national standard method. Conclusion：The method is fast, sensitive, accurate and highly selective. Thus it can be used for determination of sulfur dioxide in disposable chopsticks.