方法对比

	圆二色性	MALDI-TOF	小角X射线散射 (SAXS)
领域	光谱学	光谱学	光谱学
方法族	Process / pipeline	Process / pipeline	Process / pipeline
起源年份	1969	1988	1954
提出者	Jean-Claude Fasman	Michael Karas	Otto Kratky
类型	Spectroscopic method	Ionization and mass analysis technique	Synchrotron/X-ray technique
开创性文献	Greenfield, N. J., & Fasman, G. D. (1969). Computed circular dichroism spectra for protein secondary structures. Biochemistry, 8(10), 4108-4116.	Karas, M., & Hillenkamp, F. (1988). Laser desorption ionization of proteins with molecular masses exceeding 10,000 daltons. Analytical Chemistry, 60(20), 2299-2301.	Glatter, O., & Kratky, O. (1982). Small Angle X-ray Scattering. Academic Press.
别名	CD spectroscopy, circular dichroism, CD analysis	MALDI mass spectrometry, MALDI-TOF-MS, laser desorption mass spectrometry	SAXS, small-angle scattering
相关	3	3	3
摘要	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.	Matrix-Assisted Laser Desorption/Ionization (MALDI) combined with Time-of-Flight (TOF) mass analysis, or MALDI-TOF, is a soft ionization mass spectrometry technique that gently ionizes intact biomolecules and volatile organic compounds, then measures their mass-to-charge ratio by measuring flight time through a field-free drift region. Introduced independently by Karas, Hillenkamp, and Tanaka in 1988, MALDI-TOF revolutionized proteomics, microbiology, and organic analysis by enabling mass determination of proteins and polymers exceeding 100 kDa.	Small-Angle X-ray Scattering (SAXS) is a solution-phase X-ray scattering technique that measures the overall shape and size of macromolecules and nanoparticles by analyzing scattering intensity at low angles (0.1-10 degrees). Developed by Kratky and colleagues in the 1950s, SAXS provides information about molecular radius, aggregation state, and overall shape without requiring crystallization or fixing, making it ideal for studying native protein conformations and dynamics.