השוואת שיטות

	ATR-FTIR	דיכרואיזם מעגלי	ספקטרומטריית מס (Mass Spectrometry) מסוג FT-ICR
תחום	ספקטרוסקופיה	ספקטרוסקופיה	ספקטרוסקופיה
משפחה	Process / pipeline	Process / pipeline	Process / pipeline
שנת המקור	1961	1969	1974
הוגה השיטה	Joop Fahrenfort	Jean-Claude Fasman	Alan Marshall
סוג	Vibrational spectroscopy technique	Spectroscopic method	Mass spectrometry technique
מקור מכונן	Harrick, N. J. (1960). Study of physics of internal reflection from metals. Journal of Physics and Chemistry of Solids, 13(2), 143-155.	Greenfield, N. J., & Fasman, G. D. (1969). Computed circular dichroism spectra for protein secondary structures. Biochemistry, 8(10), 4108-4116.	Comisarow, M. B., & Marshall, A. G. (1974). Fourier transform ion cyclotron resonance spectroscopy. Chemical Physics Letters, 25(2), 282-283.
כינויים	ATR-IR, attenuated total reflectance, FTIR spectroscopy	CD spectroscopy, circular dichroism, CD analysis	FT-ICR-MS, Fourier Transform ICR, ICR mass spectrometry
קשורות	3	3	4
תקציר	Attenuated Total Reflectance (ATR) Fourier Transform Infrared (FTIR) spectroscopy is a variant of conventional FTIR that measures infrared absorption through evanescent-wave interrogation of samples in direct contact with a high-refractive-index crystal. Developed by Harrick and Fahrenfort in the 1960s, ATR-FTIR is now the dominant form of FTIR spectroscopy, enabling rapid, non-destructive characterization of organic compounds, polymers, coatings, and biological materials without extensive sample preparation.	Circular Dichroism (CD) spectroscopy measures the differential absorption of left- and right-circularly polarized light by optically active molecules, particularly proteins and nucleic acids. Introduced by Greenfield and Fasman in 1969, CD is a rapid, non-destructive technique for characterizing secondary structure (alpha-helix, beta-sheet), monitoring protein folding transitions, and assessing conformational changes in response to pH, temperature, or ligand binding.	Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometry is an advanced analytical technique that combines magnetic confinement of ions with Fourier transform data processing to achieve exceptional mass accuracy and resolution. Developed by Comisarow and Marshall in 1974, FT-ICR-MS enables the determination of exact masses and elemental compositions of complex molecules, making it invaluable for environmental chemistry, metabolomics, petroleum characterization, and structural elucidation of unknowns.