Time-resolved spectroscopy analytical applications

Volume 4 is intended to summarize the principles required for these biomedical applications of time-resolved fluorescence spectroscopy. For this reason, many of the chapters describe the development of red/NIR probes and the mechanisms by which analytes interact with the probes and produce spectral changes. Other chapters describe the unique opportunities of red/NIR fluorescence and the types of instruments suitable for such measurements. Also included is a description of the principles of chemical sensing based on lifetimes, and an overview of the ever-important topic of immunoassays. 

Fluorescence spectroscopy and its applications to the physical and life sciences have evolved rapidly during the past decade. The increased interest in fluorescence appears to be due to advances in time resolution, methods of data analysis and improved instrumentation. With these advances, it is now practical to perform time-resolved measurements with enough resolution to compare the results with the structural and dynamic features of macromolecules, to probe the structures of proteins, membranes, and nucleic acids, and to acquire two-dimensional microscopic images of chemical or protein distributions in cell cultures. Advances in laser and detector technology have also resulted in renewed interest in fluorescence for clinical and analytical chemistry. 

The application of vb-DMASP to MIPs was continued in subsequent works [64, 65], In these investigations, time-resolved fluorescence spectroscopy was applied to study bulk fluorescent MIP. The imprinted polymer fluorescence quenching with increasing concentrations of aqueous cAMP was determined from the fluorescence lifetime parameters. Two components in the fluorescence decays were identified and assigned to two different types of cavities present in the polymer matrix. One was accessible and open to binding, whereas the other was inaccessible, being buried inside the bulk polymer. The fluorescence lifetime decreased due to the increase in the concentration of the initial target analyte. However, the accessible... 

Time-resolved emission spectroscopy is gaining importance in the study of various chemical aspects of luminescent lanthanide and actinide ions in solution. Here, the author describes the theoretical background of this analytical technique and discusses potential applications. Changes in the solution composition and/or in the metal-ion inner coordination sphere induce modifications of the spectroscopic properties of the luminescent species. Both time-resolved spectra and luminescence decays convey useful information. Several models, which are commonly used to extract physico-chemical information from the spectroscopic data, are presented and critically compared. Applications of time-resolved emission spectroscopy are numerous and range from the characterization of the... 

This book is intended to introduce a student or practitioner of analytical chemistry to the technical elements and practical benefits of the Raman revolution. It is not intended to describe high-end Raman techniques such as nonlinear or time-resolved Raman spectroscopy, nor does it attempt to describe the many theoretical treatments of Raman scattering. The book emphasizes the concepts and technology important to applications of Raman spectroscopy in chemical analysis, with attention to calibration, performance, and sampling modes. While many recent innovations in analytical Raman spectroscopy are... 

Time-resolved luminescence spectroscopy complements the steady-state method and can provide essential kinetic information about the decay of excited states. Application of time-resolved fluorescence spectroscopy for analytical chemistry, where low concentrations might require the use of long... 

Molecular photophysics, especially the use of steady-state and time-resolved luminescence spectroscopy, have many important applications and there has been a progressive emergence of a new field of analytical chemistry based on these principles. It has been known for many decades that the excited state properties of certain molecules are highly sensitive to the local environment but it is only recently that a concerted effort has been made to use this sensitivity in a practical way. The main approaches to employing variations in photophysical properties as an analytical tool can be divided into two areas namely, (i) development of luminescent probes that respond to changes in the environment and (ii) identification of molecular systems for which the emission... 

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