The semiquantitative estimation of the concentration of particles in a suspension (e.g. bacterial cells in an antigenic preparation), by means of comparing it with the standard suspensions in a nephelometer.
The measurement of the cloudiness of a medium. In particular, we can determine the concentration of a suspension of particles by measuring, at more than one angle, the scattering of light transmitted or reflected by the medium.
Test to determine the concentration of solids suspended in a liquid or gas. May be used to determine the number of bacteria in a specimen.
A readily available and rapid automated laboratory method to determine the amount of myeloma protein in the blood (see ‘immunofixationâ€(tm)). Nephelometry uses a light scattering technique and should be checked against electropohoresis to ensure accuracy.
A technique used to measure turbidity by measuring the scatter of radiation (in this case light) passing through a sample. Higher scattering indicates higher turbidity.
(NEPH), is used to quantitate antigen by analyzing increases in turbidity, as measured by increasing scatter of laser light. The interaction of specific antibodies in the reagent with the antigen from the sample results in the formation of antigen-antibody complexes which are rendered insoluble by the presence of precipitating reagents. Most modern nephelometers compare the rate of formation of antigen-antibody complexes (determined by computer analysis of laser light scatter data) to that of known antigentic standards in order to measure precisely the protein antigens (some of which are actually immunoglobulins) present in moderate concentrations.
From the Greek "nephele," cloud, usually applied to measurement of the angular dependence of scattering of electromagnetic radiation by a suspension of particles.
1. The study of suspensoids by means of light-scattering techniques. See nephelometer. 2. The study of the scattering properties of small samples of air and its suspensoids. 3. Chemical analysis by use of the nephelometer.