摘要:

The sol-gel process provides a versatile method to prepare size, shape, and charge selective materials for chemical analysis. Ion-exchange sites or functionalities can be introduced into the inorganic framework as a means to preconcentrate an appropriately charged analyte into a film for detection. Template-based approaches can be utilized to design porous inorganic hosts with improved molecular recognition capabilities. Chromatographic stationary phases with excellent thermal and hydrolytic stability can be designed to separate complex mixtures. Through variations in the sol-gel processing conditions (silicon-to-water ratio, pH, type of silicon alkoxide), membranes with optimal porosity and/or hydrophobicity can be prepared for gas separation and facilitated transport applications. In this review some of the unique features and new applications of sol-gel technology are described as it pertains to the development of materials with improved molecular specificity for chemical analysis.

ISSN:1040-8347    

DOI:10.1080/10408349891199310

出版商:TAYLOR & FRANCIS    

年代:1999

数据来源: Taylor

摘要:

Regardless the progress in detectability of various instrumentation for trace metal determination, the preconcentration steps are very often needed for the analysis of environmental samples. Among the different techniques that can be used for this purpose, solid-phase extraction using various sorbents has been developed very intensively in recent years. Besides preconcentration, it can also be used for matrix removal necessary in some procedures or for the speciation of trace elements.This review is based on 42 literature references and shows favorable properties of cellulose sorbents for this purpose. Depending on the functional groups attached, the sorbent can be directly used for sorption of target analytes or can be loaded with ligands specifically binding certain species. Applications are reviewed for conventional batch procedures, flow-injection sample processing, and speciation of certain trace elements.

ISSN:1040-8347    

DOI:10.1080/10408349891199329

出版商:TAYLOR & FRANCIS    

年代:1999

数据来源: Taylor

摘要:

This review discusses the advances in the design of chemiluminescence-based sensors and biosensors with particular emphasis on their classification. Several up-to-date applications are presented.

ISSN:1040-8347    

DOI:10.1080/10408349891199338

出版商:TAYLOR & FRANCIS    

年代:1999

数据来源: Taylor