METHOD AND APPARATUS FOR CHARACTERIZING MICROPARTICLES OR MEASURING THEIR RESPONSE TO THEIR ENVIRONMENT

摘要

A process and apparatus is disclosed for characterizing an ensemble of microparticles and monitoring their response to environmental factors such as chemically and biologically active agents. The apparatus permits the very accurate measurement of light or radiation intensity scattered by the microparticles at two well-defined scattering angles with respect to the direction of the incident beam. This is achieved by measuring the scattered radiation at two sets of scattering angles each subtending the two defined angles, processing the detected intensities with a computer means to remove spurious data arising from artifacts in the scattering ensemble, and then functionally averaging the so-processed intensities of each set to yield a mean value for the scattered intensity at each of the two defined angles. Monitoring these two values before and after the addition of an environmental factor permits the calculation of a quantitative ensemble response to said environment. Applications include the quantitative determination of bacterial response to antimicrobials, determination of antigen or antibody concentrations in various fluids, detection of chemical residues in foods and other materials, identification or characterization of unknown particles ensembles by comparison with known scattering values, and detection of bactiurea. Appropriate processes and protocols are disclosed.