[Filter coated with phenyl fluorone for enrichment and determination of indium by GFAAS]

The filter fiber column coated with phenyl fluorone was extended to pre-concentrate trace amount of indium determined by GFAAS. The optimized condition for filter fiber coated with phenyl fluorone was obtained. The enrichment condition was achieved when the pregnant solution at pH 5 flowed through the filter fiber column at the rate of less than 2.0 mL x min(-1), then 8mL HNO3 of 5.00 mol x L(-1) was used as an eluent. With a general graphite tube coated with tungsten and silver as matrix modifier, the sensitivity was enhanced with GFAAS. The method was validated by the determination of trace indium in water, artificial zinc, and aluminium samples. The detection limit of the method was 0.32 ng x mL(-1), the recovery was in the range of 95.0%-101%, and the RSD was between 1.8% and 7.0%.