Filtern
Dokumenttyp
- Zeitschriftenartikel (2) (entfernen)
Schlagworte
- Analytical chemistry (2) (entfernen)
Organisationseinheit der BAM
El desarrollo de receptores sintéticos complejos basados en conceptos de la química supramolecular no garantiza en ocasiones un reconocimiento molecular selectivo. Una alternativa en ciertos aspectos más simple y prometedora es el empleo de materiales híbridos orgánico-inorgánicos preparados mediante la funcionalización de sólidos inorgánicos porosos con receptores sintéticos adecuados. El anclaje de estos sistemas coordinantes a un soporte sólido da lugar a ciertos efectos sinérgicos que no están presentes ni en el material inicial ni en el receptor por separado y que sugieren que estos nuevos materiales híbridos pueden ser empleados en el desarrollo de nuevos sensores y nuevos protocolos de reconocimiento molecular y/o iónico.
The development of synthetic receptors based in supramolecular chemistry concepts will no allow a selective molecular recognition. A more simple, convenient and innovative approach relies on the use of organic-inorganic hybrid materials. These hybrid materials will be prepared by the grafting of certain synthetic receptors onto porous inorganic solids. The grafting of these coordinating systems onto a solid support leads to synergic effects that are hardly achievable with only the synthetic receptors or the solids alone. The presence of these synergic effects suggests that these organic-inorganic hybrid materials will be used for the development of novel sensory systems and novel molecular and/or ionic recognitionprotocols.
Capillary electrophoresis (CE) is a powerful and sensitive tool for speciation analysis when combined with inductively coupled plasma mass spectrometry (ICP-MS); however, the performance of this technique can be limited by the nature of pneumatic nebulizers. This study compares two commercially available pneumatic nebulizers to a newly introduced vibrating capillary nebulizer (VCN) for on-line coupling of CE with ICP-MS. The VCN is a low-cost, non-pneumatic nebulizer that is based on the design of capillary vibrating sharp-edge spray ionization. As a piezoelectrically driven nebulization source, the VCN creates an aerosol independent of gas flows and does not produce a low-pressure region at the nebulizer orifice.
To compare the systems, we performed replicate analyses of sulfate in river water with each nebulizer and the same CE and ICP-MS instruments and determined the figures of merit of each setup. With the CE-VCN-ICP-MS setup, we achieved around 2–4 times lower sensitivity compared to the commercial setups. However, the VCN-based setup provided lower noise levels and better linear correlation from the analysis of calibration standards, which resulted in indistinguishable LOD and LOQ values from the in-house-built VCN-based and commercial setups for CE-ICP-MS analysis. The VCN is found to have the highest baseline stability with a standard deviation of 3500 cts s−1, corresponding to an RSD of 2.7%. High reproducibility is found with the VCN with a peak area RSD of 4.1% between 3 replicate measurements.