MICROPOROUS CARBON SPHERES SOLID PHASE MEMBRANE TIP EXTRACTION FOR THE ANALYSIS OF NITROSAMINES IN WATER SAMPLES (Pengekstrakan Muncung Membran Fasa Pepejal Sfera Karbon Berliang Mikro bagi Analisis Nitrosamin di dalam Sampel Air)

A simple solid phase membrane tip extraction (SPMTE) utilizing microporous carbon spheres (MCS) was developed for the analysis of nitrosamines in aqueous samples. The method termed MCS-SPMTE was optimized for various important extraction parameters namely conditioning organic solvent, extraction time, effects of salt addition and pH change, desorption time, desorption solvent and sample volume. Under the optimized conditions, the method indicated good linearity in the range of 10100 µg/L with coefficients of determination, r 2 ≥ 0.9984. The method also demonstrated good reproducibility with %RSDs values ranging from 2.2 – 8.9 (n = 3). Limit of detection (LOD) and limit of quantification (LOQ) for the method ranged from 3.2 - 4.8 µg/L and 10.9 – 15.9 µg/L respectively. Recoveries for both tap-water and lake water samples spiked at 10 µg/L were in the range of 83.2 - 107.5%.