A new modified silica gel doped with 5-(4-dimethylaminobenzylidene)-rhodanine was prepared for separation, preconcentration and determination of silver ion by atomic absorption spectrometry. This new modified silica gel was used as an effective adsorbent for the solid phase extraction of Ag(+) from aqueous solutions. The variables that influence the adsorption/desorption of trace levels of Ag(+...

Phthalate esters are endocrine disrupters or mutagens. They are widely used as plasticizers and can be usually found in environmental samples, such as food, soil and polluted air. However, it is difficult to directly determine phthalate esters owing to their relatively low concentration and complex matrices. Therefore, preconcentration and separation have become increasingly important. In recen...

Solid-phase extraction (SPE) is an effective tool for the preconcentration of trace elements and their separation from various sample constituents. Octadecyl and other alkyl-bonded silica gels are most widely used for these purposes. The fundamentals of the SPE of inorganic ions are reviewed and compared with those of related techniques (liquid-liquid extraction and reversed-phase liquid chroma...

Spectrometric techniques for the analysis of trace lead have developed rapidly due to the increasing need for accurate measurements at extremely low levels of this element in diverse matrices. This review covers separation and preconcentration procedures, and considers the features of the application with several spectrometric techniques. The use of an appropriate sample handling technique is a...

Spectrometric techniques for the analysis of trace lead have developed rapidly due to the increasing need for accurate measurements at extremely low levels of this element in diverse matrices. This review covers separation and preconcentration procedures, and considers the features of the application with several spectrometric techniques. The use of an appropriate sample handling technique is a...

This paper presents a bipolar electrode (BPE) device in a microfluidic dual-channel design for concurrent preconcentration and separation of composite DNA containing samples. The novelty of the present effort relies on the combination of BPE-induced ion concentration polarization (ICP) and end-labeled free-solution electrophoresis (ELFSE). The ion concentration polarization effect arising from ...

The potential of integration of functions in microfluidic chips is demonstrated by implementing on-chip preconcentration of proteins prior to on-chip protein sizing by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Two polymeric elements-a thin (approximately 50 microm) size exclusion membrane for preconcentration and a longer (approximately cm) porous monolith for protei...