Optimización del uso de las Placas de Inmunodifusión Radial Simple de la firma Siemens

Introduction: Single radial immunodiffusion assay is a technique with immunological base, which is reliable because of its specificity in the quantification of main immunoglobulins, although it is also used for other proteins.  Commercial immunodiffusion plates are offered with a determined number of holes where the biological samples containing protein to be quantified are placed. Objective: To evaluate the sensitivity and specificity of the modification implemented to optimize the usage of single radial immunodiffusion plates from Siemens by increasing the number of samples in the plates. Materials and Methods: An innovating procedure that allows to optimize the non-used biologically active area and use it in the quantification of other samples is presented. A parallel quantification of control samples from traditional  holes  and  the  other  ones opened in available spaces was performed in order to quantify IgG and albumin in serum and in cerebrospinal fluid.Results: Sensitivity was not affected significantly between the normal plates and the usage of the new procedure.  Regarding specificity, there are also no significant differences except in the plates used to quantify serum albumin; so, it is recommended to dilute serum samples before the application. In case of NOR and LC Partigens®, this proposed modification duplicates the number of samples to be quantified in each plate, but otherwise, it could be applied in other commercial immunoplates.Conclusions: This innovation allows to make an optimal usage of immunodiffusion plates with the consequent saving of import materials, which can be easily applied in all the laboratories of the country.Keywords: radial immunodiffusion, protein quantification, innovation, serum, cerebrospinal fluid, IgG, albumin, sensitivity, specificity, ROC curves.