Chemometrics-enhanced high performance liquid chromatography strategy for simultaneous determination on seven nitroaromatic compounds in environmental water

Nitroaromatic compounds pose a significant risk to human health and other living organisms. However, conventionally high performance liquid chromatography (HPLC) methods are complicated and time-consuming for complete separation of multiple nitroaromatic compounds due to their high structure-similarity. In the work, a facile yet effective strategy, which combines HPLC embedded by diode array detection (HPLC-DAD) with multivariate curve resolution-alternating least squares (MCR-ALS), is explored to improve the HPLC analysis. Based on the strategy, seven nitroaromatic compounds with similar structures could be rapidly quantified under a simple isocratic elution condition (acetonitrile/water: 65:35, v/v) within 10 min. With the aid of the second-order advantage of MCR-ALS, acceptable quantification results are still achieved for the real water samples, despite of significantly overlapping peaks resulted from the similar structures of the analytes and the unexpected interferences from the real water sample. The error analysis and the elliptical joint confidence region (EJCR) test further confirm the reliability of the predicted result. Thereby, the HPLC method coupled with the second-order calibration algorithm could provide a simple, quick and accurate strategy for simultaneous determination on the multiple nitroaromatic compounds in environmental monitoring.