| 초록 |
Detecting traces amounts of pollutants in liquid samples is important in many areas such as water monitoring, food quality control, and biomedical diagnostics. Due to the low amount of pollutants in the sample, preconcentration methods are used to guarantee successful extraction. While different methods of sample preconcentration exist, their performance is often compromised by the solids contained in the sample that pose challenge during the separation of the extractant after preconcentration. Here, we use surface nanodroplets for one-step liquid-liquid extraction of trace chemicals from dense suspension samples. The nanodroplets are formed on a target substrate by phase separation of a ternary containing extractant. The ternary solution is replaced by fresh poor solvent causing oversaturation, nucleation and growth of the nanodroplets. The droplets are then exposed to continuously flowing sample to extract the pollutants. The extracted chemicals in the droplets are detected by in situ methods. Using the surface nanodroplets, model fluorescent analytes, e.g. Nile red and Rhodamine B, have been extracted and detected from dense suspension samples with a detection limit of 10-9 M. |
