Affordable cellulose-based solid phase extraction adsorbent for efficient chromatographic analysis of trace contaminants in environmental waters for developing countries

The current work reports on a new low-cost solid phase extraction (SPE) material obtained by crosslinking cellulose with 4,4 –methylenebisphenyldiisocyanate (CMDI-1) for the pre-concentration of two contaminants of emerging concern (CEC): Chloramphenicol (CAP) and Bisphenol-A (BPA) from water. The results obtained show good analytical performance with low Limit of Detection of 71.9 ng/L and 10 ng/L for the pre-concentration of CAP and BPA respectively, and a good linear range between 0.5 and 8 µg/L, with r2 values > 0.99. The application of the developed method for the analysis of spiked real water samples achieved good percentage recoveries (86.8 – 96.2 %), comparable to that of an expensive commercial HLB adsorbent (89.8 – 107 %). Response Surface Methodology modelling indicates that adsorbent dose, elution volume, and sample volume had a significant influence on CAP recovery, while solution pH, elution volume, and ionic strength had a significant influence on BPA recovery. From our economic assessment, a pack of 30 SPE tubes of 500 mg CMDI-1 SPE adsorbent costs 82 % less than a similar amount of Oasis HLB adsorbent. This study demonstrates and validates a feasible and inexpensive approach to the use of cellulose to develop low-cost SPE adsorbents for the effective pre-concentration and determination of trace contaminants in water. The CMDI-1 SPE adsorbent can be easily prepared and adopted for use by water professionals in developing countries to enhance understanding on the presence and fate of such contaminants in the environment and also in technical systems, towards developing relevant environmental protection measures for sustainability.