摘要
在弱酸性介质中,碘与荧光素反应导致荧光素荧光强烈猝灭,而SO_3^(2-)的存在可以有效地抑制这种猝灭作用,使得体系荧光强度增强,籍此可测定痕量SO_3^(2-).线性范围为25～150μg/L;检出限为8.7μg/L.该法快速、灵敏、选择性好、操作简便,用于大气中二氧化硫实际样品分析,结果令人满意.
A novel fluorimetric method has been developed for rapid determination of atmospheric sulphurdioxide with fluorescein as a fluorogenic reagent (λex= 485 nm, λem = 515 nm) at pH 5.6～6.0. Inweak acidic medium, iodine reacted with fluorescein to produce a non-fluorescence species and cause the fluorescence quenching. However, this fluorescence quenching effect was largely decreased in the presence of SO32-due to the reaction between iodine and S032-. Thus, the fluorescence intensity offluorescein-I2 system enhanced when SO32- was added. The calibration graph is linear over the range 25-150μg/LSO32-. The detection limit is 8.7μg/L SO32-. The method is rapid, sensitive and simple,it has been applied to the determination of atmospheric sulphur dioxide with satisfactory results.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
1999年第11期1303-1305,共3页
Chinese Journal of Analytical Chemistry
