Cloud-point extraction/preconcentration on-line flow injection method for mercury determination

Comparison of traditional cloud-point extraction and on-line flow-injection cloud-point extraction with a chemiluminescence method using benzo[a]pyrene as a marker

“…Huie et al [9] investigated different filtering materials and found that cotton resulted in the best reproducibility. On the basis of previously reported results [9,11], moreover, an inner diameter of 3 mm and a length of 3.0 cm were used for the on-line FI CPE column in this work.…”

“…Paleologos [10] has reported the determination of metal species by on-line combination of CPE with FIA coupled with chemiluminescence detection. Analysis of mercury by on-line FI CPE has been reported by Garrido [11].…”

Enhancement in sample preconcentration by the on-line incorporation of cloud point extraction to flow injection analysis inside the chemiluminescence cell and the determination of total serum bilirubin

“…Therefore, compared to the results obtained by other authors [6][7][8][9][10][11][12][13], the present on-line CPE/FIA system had many advantages, such as high sensitivity, high sample throughput, high extraction efficiency and simplicity. Experimental factors which govern the magnitude of the preconcentration factors and the CL intensity were studied.…”

“…When compared to all the reported on-line CPE/FIA papers [6][7][8][9][10][11][12][13], the key difference/improvement of the present on-line CPE/FIA system was that the collection column served a dual function: (1) to entrap the analyte-containing surfactant aggregates and (2) to provide CL emission (i.e., the collection column was mounted directly adjacent to the detector). Table 1 shows the effects on the CL intensity as a function of the presence (or absence) of the analyte (bilirubin), surfactant (Triton X-114), salting-out agent (Na 2 SO 4 ) and/or filtering material (cotton).…”

“…The analytical capability of this automated system was demonstrated for the determination of coproporphyrin in pretreated urine samples. Subsequently, this on-line CPE/FIA methodology was adopted by other researchers for the rapid and sensitive determination of metal species [7][8][9][10][11][12] and PAHs [13]. However, the preconcentration/enhancement factors reported were lower than that predicted by theoretical calculations [14].…”