Determination of N-nitrosamines in water by nano iron-porphyrinated poly(amidoamine) dendrimer MCM-41 generation-3 through solid phase membrane tip extraction and HPLC

This study described a method comprising solid-phase membrane tip extraction (SPMTE) with nano iron-porphyrinated poly(amidoamine) dendrimer Mobil Composition Matter-41 Generation-3 (FeP-Dend-MCM-41-G3) and high-performance liquid chromatography for analysis of N-nitrosamines in water samples (tap, lake, and hospital water). The studied carcinogenic nitrosamines were N-nitrosopyrrolidine (NPYR), N-nitrosomorpholine (NMOR), and N-nitrosopiperidine (NPIP). Nano FeP-Dend-MCM-41-G3 SPMTE was evaluated in terms of efficiency for the extraction of nitrosamines from waste, lake, and tap water samples. The suitability of the chromatographic system for the separation of nitrosamines was also established. The capacity factor, k′ for NMOR, NPYR, and NPIP were 1.67, 2.50, and 6.75, respectively, with excellent selectivity factors (NMOR-NPYR, 1.497 and NPYR-NPIP, 2.70) and resolution, Rs (NMOR-NPYR, 1.81 and NPYR-NPIP, 6.00). Under the optimized conditions, the proposed method showed good relative recovery within 84%-100% and acceptable reproducibility with intra- and inter-day relative standard deviations of <11.8%. The method also showed good linearity within 1-1000 ng/mL, high enrichment factor (71-406), and low detection limits (<5.7 ng/L). The limits of detection and quantification for nitrosamines were within 0.6-0.75 ng/mL. Overall, the proposed method was efficient and required only small amounts of the adsorbent and organic solvent and, thus, contributed toward green chemistry.