![]() Fluorescence interference with visible excitation of many fats was drastically reduced at NIR wavelengths. NIR-Raman was reported to measure the total unsaturation and the cis and trans isomers online during the production process. In the production of oils and fats, the determination of the amount of unsaturation, such as cis and trans isomers, can be important for food processing and food labeling. NIR-Raman has been introduced for use into the food processing industry. In the textile industry, NIR-Raman was used to examine ready-made textiles for the discrimination of the different raw materials. With excitation at 785 or 852 nm, a good quality Raman spectrum was obtained. With He/Ne laser excitation at 633 nm, several Raman features appeared above the background. In a study examining unleaded petroleum gasoline, with excitation at 514 nm from an argon laser, no Raman features were observed above the strong fluorescence. In this study, the authors describe the simultaneous detection of two pesticides, carbenazim and metazachlorine.Ī variety of industrial processes benefit from the use of NIR-Raman spectroscopy. This method uses NIR excitation and FT-SERS detection to detect parts per million of pesticides in aqueous solutions. A continuous method was developed by Weissenbacher and colleagues to detect trace organic pollutants using flow injection analysis and surface enhanced Raman spectroscopy (SERS). The environmental community has also found uses for NIR-Raman analysis. This work demonstrated the potential of NIR-Raman for online process monitoring. ![]() Using a library of spectra, identification of the pharmaceuticals in the vials was performed and identification was found to display accuracy between 88% and 96%. Even with the signal attenuation through the glass, adequate spectra were obtained for determination of vial content with 1–60 s integration times. McCreery and colleagues reported the use of the technique for identification of pharmaceuticals inside amber vials. NIR-Raman has found applications in the pharmaceutical industry. The usefulness of NIR-Raman coupled with CCD detection for studying cancerous changes in the colon, urinary bladder, breast, and soft tissue sarcomas has also been examined. Subsequent work showed that fluorescence interference in tissue Raman spectra could be reduced even further using 830-nm excitation without compromising CCD sensitivity. In a specific study, an 810-nm excitation wavelength was used for in vitro laboratory analysis of aorta tissues. Several research groups have described NIR-Raman instrumentation with CCD detection for biological tissue analysis, both in vivo and in vitro. Although spectra could not be collected in vivo due to long integration times, NIR-Raman was found to have specificity that was superior to standard methodologies, such as coloscopy and cytology, for differentiating squamous intraepithelial lesions (SIL) from non-SIL. NIR-Raman has been evaluated as a diagnostic tool for cervical precancers. Interest in both in vivo and in vitro use of NIR-Raman spectroscopy of tissues for diagnostics continues to grow. NIR excitation reduces interference from fluorescence and decreases photoinduced degradation of the sample, enabling researchers to obtain spectra for a variety of biomaterials and living cells. Fluorescence has been a limiting factor for much Raman analysis of biological samples, particularly whole-cell or whole-tissue samples. NIR-Raman spectroscopy has been used for a number of applications and is particularly useful for biological and biomedical uses. ![]() Carron, in Encyclopedia of Analytical Science (Second Edition), 2005 Applications
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |