Compiled evaluation parameters for the protein nanoparticles.
S. number
Parameter
Specification
Ref. number
Particle size
Due to their size and mobility nanoparticles have higher intracellular uptake as compared to microspheres. It was also reported that nanoparticles have the ability to cross blood brain barrier due to the opening of tight junctions by hyper osmotic pressure which helps to give sustained release of therapeutic agents.
In this method the time decay of the near particle caused by the Brownian motion which helps to evaluate nanoparticle via Strokes–Einstein relation and the interpretation of particle size is least ambiguous with a narrow distribution, an effective diameter and polydispersity index are measurable even with broad distributions. The major disadvantage of this technique is it does not produce a high-resolution histogram of the size distribution.
To observe the physicochemical properties which lead to revolutionize electronic, diagnostic, and therapeutic applications.
Atomic microscopy (AFM)
This tool used for direct measurements of microstructural parameters and unraveling the intermolecular forces at nanoscale level with atomic-resolution characterization.
It helps to identify the signals that derive from electron-sample interactions reveal information about the sample including external morphology (texture), chemical composition, and crystalline structure and orientation of materials making up the sample. It has high resolution type of fractions, more than 1000 times better than the optical diffraction and particle surface was scanned under high energy beam.
Zeta potential analysis is a technique for determining the surface charge of nanoparticles in solution (colloids) which possess a positive or negative electrostatic charge. Zeta potential also helps to understand the nanoparticle surface and predicting the long term stability of the nanoparticle.
Drug loading can be defined as the amount of drug bounded per mass of polymer usually in moles of drug per mg of polymer. Drug can be bound to nanoparticles either by the polymerization or adsorption.
Determined the UV-spectrophotometer or HPLC absorbance. The amount of drug in supernatant was subtracted from the total amount of drug added during formulation . Effectively, will be amount of drug entrapped in the nanoparticles- Drug entrapment (%) = / × 100.
To analyze the nature and modification in confirmation, folding, and chemical bonding.
X-ray diffraction
The purpose of XRD is to investigate the structure of crystalline materials and also analyze their phase composition, crystallite size, shape, lattice, etc.
The principle of FTIR provides that a molecule is exposed to infrared rays absorbs infrared energy at frequencies which are characteristic to that molecule and provide information about the structural details of proteins in solution with greater spatial and temporal resolution.
Cellular uptake of nanoparticles is determined by tagging the nanoparticles with fluorescent tags followed by incubating these fluorescence-tagged nanoparticles with cells and their visualization under confocal laser scanning microscope.