Preparation of nylon-6 modified cellulose paper for extraction and determination of perfluoroalkyl substances in water

A nylon-modified cellulose paper was prepared from raw cellulose paper by esterification reaction and physical coating, and then used to extract emerging contaminants of perfluoroalkyl substances (PFASs) in water, followed by UPLC-MS/MS analysis. The SEM, FT-IR, TGA and XPS analysis indicated that the modifier nylon-6 was successfully adsorbed on the surface of raw cellulose paper. The solution pH had little effect on PFASs extraction by nylon-modified cellulose paper, and the recoveries of the nine targeted PFASs had a maximum at pH 5.0. Adsorption experiments showed that nylon-modified cellulose paper can adsorb the PFAS targets mainly by a combination of hydrogen bonding and hydrophobicity. The recoveries of PFASs extracted by nylon-modified cellulose paper in real water samples such as groundwater and wastewater under external standard method conditions ranged from 54.5% to 90.5%. The limits of detection (LODs) and limits of quantification (LOQ) were in the range of 0.05-1.85 ng/L. The nylon-modified cellulose paper had similarly excellent recovery performance as the commercial HLB columns. Thus, the use of environmentally friendly cellulose resources for the enrichment and detection of PFASs in water is informative for green and sustainable development.