COMBINING FINGERPRINTING CAPABILITY WITH TRACE ANALYTICAL DETECTION -SURFACE-ENHANCED RAMAN-SPECTROMETRY

The demand to measure unique spectral information on trace analytes in complex samples continues to increase. This paper discusses surface-e nhanced Raman spectrometric (SERS) methods which are currently being e xplored for molecular recognition at trace concentration levels. SERS is amenable to the analysis of solids, liquids and gases in a variety of experimental configurations for both qualitative and quantitative t asks. Batch and flow systems are also easily implemented in colloid SE RS experiments. Typical instrumental systems for each of these analyti cal approaches are described and compared. The shape of the calibratio n graphs and the factors limiting the linear range of response are dis cussed. Other figures of merit, including limits of detection, precisi on and selectivity of measurement, are given. Applications to compound s of technical, environmental, biomedical and pharmaceutical interest are presented.