Fourier transform infrared evanescent wave (FTIR-FEW) spectroscopy of tissue

Factor analysis of cancer fourier transform infrared evanescent wave fiberoptical (FTIR-FEW) spectra

“…A ik = ͚ j=1,n e ij c jk (2) where e ij is the molar absorptivity per unit pathlength of component j at wavelength i, and c jk is the molar concentration of component j in the k th mixture. The first component or factor has the largest eigenvalue and accounts for the greatest variance in the data matrix, the second factor is orthogonal to the first factor and has the second largest eigenvalue.…”

“…Specific biochemical constituents of tissue can be used to reflect the health or disease state of patients when probed spectroscopically [1][2][3][4][5][6][7][8]. Unlike conventional methods, FTIR-FEW spectroscopy, in the middle infrared (MIR), probes tissue biochemistry at a molecular level [1][2][3][4] and the observed MIR spectra exhibit superimposed or composite vibrational bands. It is therefore strategic for FTIR-FEW spectroscopy to employ advanced computational methods for analysis and interpretation of obtained spectra.…”

“…With recent advances in fiberoptic technology Fourier transform fiberoptic evanescent wave (FTIR-FEW) spectroscopy has become a powerful new method for human skin tissue analysis in vivo [1][2][3][4]. Specific biochemical constituents of tissue can be used to reflect the health or disease state of patients when probed spectroscopically [1][2][3][4][5][6][7][8].…”

“…However these type of pattern recognition techniques [9][10][11][12] are mathematically abstract and do not take advantage of the specific biochemical information contained in the MIR spectra. The aim of this study is to assess the useful-ness of FTIR-FEW spectroscopy method [1][2][3][4] combined with chemical factor analysis [13] to discriminate between different types of skin cancer and isolate eigenspectra of active biochemical species. In this work some of the eigenspectra extracted by chemical factor analysis have been preliminarily identified as due to peptide bonds and lipid carbonyls.…”

Vibrational spectroscopic studies of newly developed synthetic biopolymers

“…14 Particularly, two vibrational spectroscopic techniques namely FTIR and Raman spectroscopies are commonly used as complementary analytical tools for in situ and in vivo measurements of samples of biological origin. [15][16][17][18][19][20] This is mainly due to their unique capability of providing labelfree intrinsic chemical and structural information of living biological samples at tissue, cellular, or sub-cellular resolutions. 21 In addition, Raman spectroscopy is well-suited for studying the structure of lipids because this technique is noninvasive, nondestructive, and involves no labeling as well as minimal sample preparation.…”