TANG Jinlan, LU Yanfei, BAO Yilin, ZHAO Yuan, SHANG Linwei, YIN Jianhua
Abstract (
)
Download PDF (
)
Knowledge map
Save
Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic technique can be used to directly measure infrared spectra of biological tissues. In this study, a home-made hollow core optical fiber (HOF)-ATR probe coupled FTIR spectrometer was firstly used to achieve in-situ spectral detection of healthy and cancerous breast tissues. The deconvolution, second derivative and curve fitting methods were used to analyze the amide I band (1700-1600 cm-1) of the measured spectra for content information of each secondary structure of protein in breast tissue. The significant difference in the secondary structures was found as below. The content of β-sheet, random coil and atypical helix in cancerous breast tissue is lower than that in normal breast tissue, and the content of α-helix and β-turn is higher than that in normal breast tissue. Comparing with normal breast tissue, secondary structure-content analysis shows that collagen and fibroin decrease and alpha-keratin synthesis increases in cancerous breast tissue, preliminarily indicating the related cancerization mechanism. Furthermore, partial least squares discrimination analysis model was established by using the amide I band and the full spectra, respectively, and it was found that the distinguish accuracy (81.8%) and stability of the discriminant model established only with the amide I band were significantly lower than those of the full spectra model (97%). This indicates that although the amide I band contains a lot of information of the changes in protein secondary structure, it is still not enough to replace the changes in other major biological components to accurately distinguish cancerous tissues. The study on HOF-ATR-FTIR spectroscopic technology applied on secondary structure analysis of protein is very helpful for deeply understanding the cancerization mechanism of breast tissue at the molecular level, and provides an effective method for in-situ detection and accurate identification of tissue cancerization.
