Automated and portable solid phase extraction platform for immuno-detection of 17β-estradiol in water

A fully automated and portable system for solid phase extraction (SPE) has been developed for the analysis of the natural hormone 17β-estradiol (E2) in environmental water by enzyme linked immuno-sorbent assay (ELISA). The system has been validated with de-ionized and artificial sea water as model samples and allowed for pre-concentration of E2 at levels of 1, 10 and 100 ng/L with only 100 ml of sample. Recoveries ranged from 24±3% to 107±6% depending on the concentration and sample matrix. The method successfully allowed us to determine the concentration of two seawater samples. A concentration of 15.1±0.3 ng/L of E2 was measured in a sample obtained from a food production process, and 8.8±0.7 ng/L in a sample from the Adriatic Sea. The system would be suitable for continuous monitoring of water quality as it is user friendly, and as the method is reproducible and totally compatible with the analysis of water sample by simple immunoassays and other detection methods such as biosensors.