Table 1.

Investigative strategies used to contemplate protein structure, folding, and aggregation.

TECHNIQUES	PRINCIPLE	SIZES	OBSERVABLE
Atomic force microscopy	Topographical scanning	0.01 nm	Molecular resolution
Size exclusion chromatography	Separation through porous matrix based on size.	5–50 nm	hydrodynamic scattering
Analytical ultracentrifugation	Sedimentation rate in response to centrifugal force.	1–100 nm	Molecular weight and confirmation
Field flow fractionation	Separation by flow retention based on the diffusion coefficient	1–1000 nm	Hydrodynamic diameter
Dynamic light scattering	The fluctuation of scattered light signals	0.5–10 μm	Hydrodynamic diameter
Mass spectroscopy	Detection of mass/charge ratio of ionized molecule	Atomic resolution Dalton	Mass/charge ratio
Optical microscopy	Visualization of protein particles	1 μm-mm	Size and morphology
Electron microscopy	Visualization of protein particles and detection of chemicals at high resolution	nm-mm	Size and morphology