Baxter Travenol Laboratories, Inc.

Baxter Laboratories, Inc.

Rodolfo R Rodriguez

Eugene K Achter

Jerome C Kremen

Paolo Priarone

Stephen G Hauser

Charles I Soodak

James H Macemon

Herbert Goldsmith

James G Bruni

David L Lessner

George M Coker, Jr

Carlton D Deaton

Horton E Dorman

Paul Priarone

Keith S Keith

An improved nephelometer for immunochemical complex assay measures forward light scatter in samples. The angle of forward scatter, about 30.degree., is small enough to result in a large amount of forward scatter from the immunochemical complex particles which are to be assayed, whose size is of the order of the wave length of the light used in the optical system. Forward scattering from smaller particles, such as from molecules of buffer, antibody and serum, is constant during the course of a test, and is compensated for by the use of subtraction circuits which are readily and semiautomatically adjusted to subtract proper values, in accordance with the readings taken on standard or 'blank' samples of buffer, antibody and serum. Forward scattering from large particles, such as dust, is variable, and results in fluctuating signals, which are electrically processed to ignore the spurious peaks. The results of a test are displayed on a digital read out meter. Also described is a method of and protocol for immunochemical assay, whereby the amount of antigen originally present in a sample is determined by adding a known amount of antibody, and by assaying the 'blank' component ingredients and the resulting mixture.

Nephelometer having means semiautomatically canceling components from

Nephelometer and nephelometer method for assaying immunochemical complex

The modular chemical analysis system includes a first module or sample preparation apparatus for preparing sample solutions, a second module including a nephelometer apparatus comprising a stationary flow cell, mechanisms for moving sample solutions into and out of the flow cell, light generating means for passing light through the flow cell, electric circuitry for sensing the relative light scattered (R.L.S.) by the solution or particles in the solution in the flow cell and a third module comprising a microprocessing/calculator having a tape cartridge program. The microprocessor is coupled to the nephelometer apparatus (and, if desired, is also coupled to the sample preparation apparatus) for controlling operation of the nephelometer apparatus (and, if desired, to control the sample preparation apparatus). Also, the output from the nephelometer apparatus is coupled to the microprocessor which receives R.L.S. values and known concentration values for some solutions from which R.L.S. values were obtained. The microprocessor then calculates curve fit parameters for a polynomial regression curve equation, performs a Newton-Raphson inversion on the equation and calculated parameters to automatically calculate concentration values for R.L.S. values obtained from unknown test solutions thereby to obtain calculated concentration values from R.L.S. measurements.

Modular chemical analysis system

Nephelometer

A high pressure xenon arc illuminator bulb having a sapphire window generates a broad band of ultraviolet, visible and infrared radiation extending from about 180 nanometers to about 2000 nanometers. The emitted radiation in the range from about 180 to about 200 nanometers, in passing through the oxygen in the air, causes the molecules of oxygen in the form O.sub.2 to recombine to produce ozone, O.sub.3. Ozone is toxic. In the invention, a lens barrel, which holds a sapphire condensing lens, is joined to the xenon arc illuminator bulb with a lighttight and also hermetic connection. Thus, the condensing lens is optically rigid with the illuminator bulb and the ozone formed within the lens barrel is not released to the ambient environment, even though its local concentration within the lens barrel becomes high. Furthermore, the ozone confined within the lens barrel acts as an absorption filter for all of the wavelengths in the 180 to 200 nanometer band which are capable of producing ozone. The ultraviolet and other radiation leaving the sapphire condensing lens therefore does not produce toxic ozone in the ambient environment.

Integrally focused low ozone illuminator

Nephelometer having means semiautomatically cancelling  components from

Growing community of inventors

Columbia, MD, United States of America

Rodolfo R Rodriguez