Real-time Non-invasive Technique Research Articles

Edible Oils Differentiation Based on the Determination of Fatty Acids Profile and Raman Spectroscopy—A Case Study

This study proposes a comparison between two analytical techniques for edible oil classification, namely gas-chromatography equipped with a flame ionization detector (GC-FID), which is an acknowledged technique for fatty acid analysis, and Raman spectroscopy, as a real time noninvasive technique. Due to the complexity of the investigated matrix, we used both methods in connection with chemometrics processing for a quick and valuable evaluation of oils. In addition to this, the possible adulteration of investigated oil varieties (sesame, hemp, walnut, linseed, sea buckthorn) with sunflower oil was also tested. In order to extract the meaningful information from the experimental data set, a supervised chemometric technique, namely linear discriminant analysis (LDA), was applied. Moreover, for possible adulteration detection, an artificial neural network (ANN) was also employed. Based on the results provided by ANN, it was possible to detect the mixture between sea buckthorn and sunflower oil.

In vivo fluorescence spectroscopic monitoring of radiotherapy in cancer treatment

Purpose: The primary purpose of this study is to introduce fluorescence spectroscopy technology as a tool for optical biopsy and to evaluate the reliability of this real-time non-invasive technique in assessing tumor therapeutic response in radiotherapy. Methods: Four oral cancer patients with inflammatory conditions of the oral cavity volunteered to participate in the study. Using FastEEM (Excited Emission Matrix), spectra were taken from both normal and tumor regions. Then the second optical diagnostic was taken from the tumor regions in 4 patients with time delay of 4 weeks. The fluorescence spectroscopy optical biopsy turned out to be more suitable for tumor diagnostics as there was a significant difference in fluorescence spectra. Results: The first fluorescence intensity of cancerous tissue was higher compared to the second fluorescence intensity of optical biopsy of cancerous oral tissue. From this result, it can be concluded that the fluorescence spectroscopy optical biopsy, which is a technique that does not require removal of tissue sample from body, is a reliable tool to be used in radiotherapy. Conclusion: FastEEM, which is a tool for fluorescence spectroscopy, enables a real-time non-invasive assessment of the chemical, biological, as well as morphological variations in the tissue composition following radiotherapy.