Sıvı sistemlerde azaltılmış toplam yansımalı fourier dönüşümlü kızılötesi spektroskopisi : biyomedikal ve gıda alanlarında tanı ve taramada uygulama örnekleri


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye

Tezin Onay Tarihi: 2013

Tezin Dili: İngilizce

Öğrenci: Seher Gök

Danışman: FERİDE SEVERCAN

Özet:

ATR-FTIR spectroscopy offers highly specific, sensitive, label free and non-destructive analytical examination opportunity for biological systems. Despite the many progresses in order to improve biological applications of this powerful technique, there has not yet been acquired enough end user data that were exemplified by proper case studies. Here, two case studies, from biomedical and food areas were retrieved to illustrate the influential potential of ATR-FTIR technique for diagnosis and screening of biological systems. In the first case study, ATR-FTIR spectroscopy was used for the investigation of bladder tumor presence, using bladder wash sample. Current gold standard diagnosis techniques have some inadequacies. Macromolecular investigations on the ATR-FTIR spectra showed up many carcinogenesis induced differences between control and carcinoma groups. Conspicious increase in nucleic acid and protein content was revealed in carcinoma group in addition to the structural changes in carbohydrate and proteins. Discrimination sensitivity and specificity in the 1100-900 cm-1 spectral region, with the values of 92.5% and 68% respectively, were achieved by hierarchical clustering of control and carcinoma samples. Attained results demonstrated that, ATR-FTIR can be used for bladder tumor detection from bladder wash sample with higher overall sensitivity than urine cytology. In the second case study, ATR-FTIR spectroscopy was coupled with multivariate analysis including Principal Component and Hierarchical Clustering analysis for the classification of Turkey honey samples based on their botanical origin. For botanical origin estimations, new analytical techniques have been looked for as an alternative to labor intensive and less sensitive classical techniques. It is the first time that the Turkish honey samples have been investigated experimentally for botanical origin estimation with ATR-FTIR. Discrimination was achieved with 100% sensitivity and specificity over the spectral range of 1800-750 cm-1 with cluster analysis. PCA results also in consisted with the hierarchical clustering analysis results.