ABSTRACT
The coupling of an enzyme immunoassay with a superheated water extraction is an attractive technique because of the reduced use of hazardous solvents, due to their hostile impact on the environment. This paper describes the use of superheated water extraction and enzyme immunoassay (EIA) for the determination of polycyclic aromatic hydrocarbons (PAHs) in native (not spiked) surface soil and sediment samples. The extraction recoveries with superheated water were comparable to those achieved with conventional Soxhlet techniques. The benefits of superheated water extraction-EIA includes replacement of harmful organic solvents used in extraction, fast extractions (15-30 min.) with an inexpensive extractant, reduced number of steps in the determination of the target compounds, and the application of sensitive and relatively inexpensive assays. Further advantages of the superheated water extraction are higher extraction efficiencies compared with the methanol based extraction kits associated with the EIA and direct measurement of the extracts with EIA. Both techniques can be used as efficient screening methods in the field since the type of equipment used in superheated water extraction and EIA can be loaded into a van and operated on a car battery or a small generator.
ABSTRACT
The reaction of three platinum compounds, Pt(NH3)2Cl2, Pt(en)Cl2 and Pt(pn)Cl2 with nucleic acid fragments (Ade, Gua; GpG, GpA and ApA), both reactants (1:1, 1 X 10(-2) M; 1 X 10(-3) M) being dissolved in water, has been studied. UV measurements have been used to characterize the products. Kinetics and adduct formation in the nucleoside-Pt compound system were studied by reversed-phase high-performance liquid chromatography [gradient 0-30% methanol in 30 min, ammonium acetate buffer (0.1 M) at pH 4.25] at fixed intervals of time and the product formation was examined by measuring the peak heights. After 10 h, the reaction was complete for guanosine and showed a steady state for adenosine. The increasing lipophilicity in the sequence of the platinum compounds resulted in a shift to longer retention times.
