Conservative whole blood sample preparation technique

Abstract

The method of this invention is directed to the rapid preparation of a whole blood sample for photooptical analysis. In the preferred embodiments of this method, a whole blood sample, lytic reagent system and immunological stain (optional) are contacted with the sample in a common reaction vessel (i.e. cuvette or test tube), with gentle asymmetric vortex mixing, so as to maintain the particulate matter of the sample at an essentially homogeneous concentration throughout the sample. An aliquot of the contents of the reaction vessel can, thereafter, be analyzed for identification and/or quantification of the analyte of interest. This process is conservative of the various endogenous constituents of the sample since virtually all of the manipulative steps involved in the preparation of the sample occur within a common vessel and any excess (unconsumed or unreacted) reagents and stain need not be separated from the sample during such preparation, thus, avoiding the multiple wash steps traditionally associated with this process. This process is uniquely applicable to the conservative preparation of aged whole blood samples (samples in which the endogenous nutrients have been essentially completely consumed) and whole blood samples from diseased state patients wherein the disease is manifest by changes in the morphology, total number and/or relative concentration of one or more of the lymphocyte subpopulations (i.e. B and/or T-cells).