In this study, a simple, fast, portable, environment-friendly and inexpensive method, CPE-scanometry, is applied for the determination of Phenylalanine (Phe) amino acid. The extraction of analytes from water samples (15 ml) was performed in the presence of Triton X-114 as a non-ionic surfactant in a water bath environment, diluting the extracted surfactant-rich phase with alkali ethanol as a suitable solvent to 0.5 mL and transferring an appropriate volume to a special cell. The individually cylindrical cavities in the sheet of Plexiglas serve as reaction chambers. These cylindrical cavities in the sheet of Plexiglas are fabricated with a laser beam. The cells containing the analyte solution were scanned with a scanner, then the color of each cell was analyzed, by software written in Visual Basic (VB 6), to obtain the red, green and blue values. The influence of operation parameters including pH, concentrations of surfactant and electrolyte on the cloud point extraction of analyte were studied and optimum conditions were established. Under optimum condition, limit of detection (LOD), relative standard deviation (RSD) and linear range for the proposed method are obtained 0.06, 3.42 and 0.2-10.0 mg L-1 respectively. Finally, the proposed method was utilized successfully for the determination of Phenylalanine in some water and waste water samples in recoveries range 94.1–107.7%.

In this research, scanometry was used as a new, simple, fast and inexpensive method for a colorimetric determination of Mn2+ ion in water samples and thermocouple wire through the use of periodate reagent in an acidic medium. The results showed the oxidization of colorless Mn2+ ion by periodate and the formation of a purplish MnO4- ion. The system had a linear range of 1.0 to 70.0 µg mL-1 Mn2+ ion with a detection limit of 0.314 µg mL-1 and a relative standard deviation of 2.77% for G color value. This method has the capability to determine low levels of Mn2+ ion in thermocouple wire and water samples.

A simple preconcentration method of silicon based on coprecipitation with aluminum hydroxide prior to its flame atomic absorption (FAAS) determination was established. The recovery values of analyte ion was higher than 95%. The parameters including types of hydroxide ion source for precipitation, acid type for dissolution step, amount of aluminum ion as collector, pH, temperature, standing and centrifuge time, and sample volume were optimized for the quantitative recovery of the analyte. The influences of matrix ions were also examined. The relative standard deviation was found to be 3.2%. The limit of detection was calculated as (0.1 mg L-1). The preconcentration factor is 100 for (200 mL) solution. The proposed method was successfully applied for the determination of silicon in some water and alloy samples.

A simple, sensitive and selective cloud point extraction procedure is described for the preconcentration and atomic absorption spectrometric determination of Zn2+ and Cd2+ ions in water and biological samples, after complexation with 3,3',3",3'"-tetraindolyl (terephthaloyl) dimethane (TTDM) in basic medium, using Triton X-114 as nonionic surfactant. Detection limits of 3.0 and 2.0 µg L-1 and quantification limits 10.0 and 7.0 µg L-1were obtained for Zn2+ and Cd2+ ions, respectively. Relative standard deviation was 2.9 and 3.3, and enrichment factors 23.9 and 25.6, for Zn2+ and Cd2+ ions, respectively. The method enabled determination of low levels of Zn2+ and Cd2+ ions in urine, blood serum and water samples.

A simple and fast approach for solid phase extraction is herein described, and used to determine trace amounts of Pb2+ and Cu2+ metal ions. The solid phase support is sodium dodecyl sulfate (SDS)-coated γ-alumina modified with bis(2-hydroxy acetophenone)-1,6-hexanediimine (BHAH) ligand. The adsorbed ions were stripped from the solid phase by 6 mL of 4 M nitric acid as eluent. The eluting solution was analyzed by flame atomic absorption spectrometry (FAAS). The sorption recovery of metal ions was investigated with regard to the effects of pH, amount of ligand, γ-alumina and surfactant and the amount and type of eluent. Complexation of BHAH with Pb2+ or Cu2+ ions was examined via spectrophotometry using the HypSpec program. The detection limit for Cu2+ was 7.9 µg L-1 with a relative standard deviation of 1.67%, while that for Pb2+ was 6.4 µg L-1 with a relative standard deviation of 1.64%. A preconcentration factor of 100 was achieved for these ions. The method was successfully applied to determine analyte concentrations in samples of liver, parsley, cabbage, and water.

A very simple cloud point extraction (CPE) methodology for the preconcentration of trace amounts of silver and magnesium as a prior step for their determination by flame atomic absorption spectrometry (FAAS) has been developed. The method is based on the extraction of silver and magnesium at pH 10 by using non-ionic surfactant Triton X-114 and 4 methyl-3-((1-H-Indol-3-iyl) (phenyl) methyl)) -1-H-Indol (MPBIM) as a complexing agent. Several important variables that affect the CPE efficiency and FAAS signal were investigated and optimized. The calibration curves, using the preconcentration system, were linear in the range of 0.007-0.200 μg mL-1 with a correlation coefficient of 0.999. The lower limits of detection (3s) obtained in the optimal conditions were 1.47 ng mL-1 and 3.00 ng mL-1 for Mg²+ and Ag+ ions, respectively. The relative standard deviation for five replicate determinations of magnesium and silver at 0.133 μg mL-1 concentration level, were 1.17 and 0.97, respectively. The proposed method was successfully applied to the ultra-trace determination of silver and magnesium in various water samples, blood serum, urine, and radiology film samples.

In this work carrier-facilitated transport of mercury(II) against its concentration gradient from aqueous 0.04 M hydrochloric acid solution across a liquid membrane containing isopropyl 2-[(isopropoxycarbothiolyl)disulfanyl]ethane thioate (IIDE) as the mobile carrier in chloroform has been investigated. Sodium thiocyanate solution (1.6 M) was the most efficient receiving phase agent among several aqueous reagents tested. Various parameters such as investigated. Under optimum conditions the transport of Hg(II) across the liquid membrane is more than 97% after 2.5 h. The carrier, IIDE, selectively and efficiently could able to transport Hg (II) ions in the presence of other associated metal ions in binary systems.

A simple cloud point extraction procedure is presented for the preconcentration of copper in various samples. After complexation by 4-hydroxy-2-mercapto-6-propylpyrimidine (PTU), copper ions are quantitatively extracted into the phase rich in Triton X-114 after centrifugation. Methanol acidified with 0.5 mol L-1 HNO3 was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). Analytical parameters including concentrations for PTU, Triton X-114 and HNO3, bath temperature, centrifugation rate and time were optimized. The influences of the matrix ions on the recoveries of copper ions were investigated. The detection limits (3SDb/m, n=4) of 1.6 ng mL-1 along with enrichment factors of 30 for Cu were achieved. The proposed procedure was applied to the analysis of environmental samples.