A novel automatic stepwise injection headspace single-drop micro-extraction system is proposed as a versatile approach for automated determination of volatile compounds. The system application is demonstrated for ammonia determination in concrete samples. An ammonia gas was produced from ammonium ions and extracted on-line into 5 μL 0.1M H3PO4 to eliminate the interference effect of concrete species on the ammonia stepwise injection spectrophotometric determination. The linear range was 0.1-1 mg kg(-1) with LOD 30 µg kg(-1). The sample throughput was 4 h(-1). This system has been successfully applied for the determination of ammonia in concretes.

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http://dx.doi.org/10.1016/j.talanta.2014.04.081DOI Listing

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