Comparison of specific protein assays in biological fluids by radial immunodiffusion and laser nephelometer.

Laser immuno-nephelometry is presently being used for measuring concentrations of specific proteins in biological fluids. Our findings have not substantiated the highly correlative results with radial immunodiffusion that have been reported. The reason for our poor correlation was found in the lack of uniformity in expressing concentrations of the different specific proteins in the calibrating standards. One value of the laser nephelometer was the greater precision obtained when comparing results to those measured by radial immuno-diffusion. Also, the laser was found to be more sensitive for measuring low level concentrations.