Determination of ~(90)Sr in environmental samples using solid phase extraction chromatography

摘要

A simple and rapid method based on solid phase extraction chromatography (SPEC) has been developed for the determination of ~(90)Sr in environmental samples. The SPEC method consists of three steps, namely, (1) carbonate precipitation of alkaline earths, (2) column separation of strontium using 4,4′(5′)-bis(tert-butylcyclohexano)-18-crown-6 based Sr spec resin and (3) beta counting of SrCO_3 using low background gas flow counter. Minimum detection limit (MDL) of low beta gas flow counter is 1.42 Bq/kg for 10,000 s counting time. The capacity of the column for strontium was about 12.2 ± 0.5 mg of Sr per g of Sr spec resin. The SPEC method using Sr spec resin was standardized with ~(90)Sr spiked samples and tested on sediment samples of Mumbai harbour bay. The average activity concentration of ~(90)Sr in sediment samples was found to be 2.2-13.7 Bq/ kg. The results obtained by SPEC method have been found to be in good agreement with conventional gravimetric method.