Table 3.

Summary of analytical techniques to conduct physico-chemical characterisation, monitor nanoparticle surface driven protein conformational changes and uptake of nanoparticles by cellular structures

Analysis of	Analytical technique	Brief description	Ref
Nanoparticle physical characterisation
Size and charge	Dynamic light scattering	Changes in the hydrodynamic diameter of NP upon binding to proteins	[1]
	Analytical Ultracentrifugation	Changes in the hydrodynamic diameter of NP	[6]
Dissolution	Inductively coupled mass spectrometry	For detecting elemental composition of the nanomaterial	[90]
Shape and structure	X ray diffraction	Determination of crystalline structure	[38]
	Electron microscopy	Visualisation of nanoparticle structure
Surface area	Braunauer Emmet Teller method	Measures specific surface area using adsorption of gas on the surface	[38]
De-agglomeration	Ultrasonication	Uses sound energy to disrupt large aggregates of NP	[36]
Nanoparticle protein interaction
Protein binding affinity	Isothermal calorimetry	To measure binding constant, thermodynamic parameters of NP-protein interactions	[2]
	Fluorescence spectroscopy	Measures change in fluorescence spectra due to NP-protein interaction	[65]
	UV–vis spectroscopy	Measures change in absorption spectra due to NP-protein interaction	[57]
	Quartz crystal balance	Detects change in mass at the oscillating quartz surface due to NP-protein interaction	[91]
	Surface Plasmon resonance	Detects change in oscillation of electrons on a metal surface due to NP-protein interaction	[92]
	Atomic force microscopy	Gives surface profile of the nanomaterial	[93]
	Fluorescence correlation spectroscopy	Binding characteristics depending on fluctuation in florescence	[94]
Nanoparticle surface induced protein structure changes
Protein structural changes after binding	Circular Dichroism spectroscopy	Measures changes in secondary structure of proteins depending on chiral properties of proteins	[61]
	Fourier transformed infrared spectroscopy	Measures adsorption of amide bonds in the proteins to derive structural change	[43]
	Raman spectroscopy	Studies molecular vibrations to predict structure	[52]
	Nuclear Magnetic Resonance	Relies on magnetic properties of atomic nuclei to predict structure	[4]
Nanoparticle- Cellular interactions
NP uptake	Confocal microscopy	Visualization of fluorescent nanoparticles in vitro	[59]
	Confocal micro Raman spectroscopy		[95]