Cell-Based Assay for the Detection of Toxic Analytes

Abstract

Assays for detecting potentially toxicdanalytes utilize a preparation of eukaryotic or prokaryotic cells which have signal-generating metabolic activity. The sensitivity of such assays is significantly improved by the employment of a particulate solid-phase adsorbent e.g. silica gel, which can be preliminarily mixed either with the suspected toxic analyte or with the cellular reagent. It is found that the presence of either the adsorbent-analyte combination or the adsorbent-cellular reagent combination results in an amplification of the decrease of the intensity of the generated signal, thereby improving the detection capability of the assay, particularly with respect to low concentrations of toxicants.

1 - 20 . (canceled) 
     
     
         21 . An assay reagent comprising a preparation of eukaryotic or prokaryotic cells having signal-generating metabolic activity, wherein the preparation of cells is immobilized onto a particulate carrier. 
     
     
         22 . An assay kit comprising the assay reagent of  claim 21  and containers for contacting the assay reagent with an analyte. 
     
     
         23 . The assay kit of  claim 22  wherein the assay reagent comprises a preparation of cells that has been freeze-dried as a mixture with a carrier, and which kit further comprises a reconstitution buffer suitable for resuspending or reconstituting the freeze-dried assay reagent. 
     
     
         24 . An assay reagent comprising immobilizing or adsorbing onto a solid-phase carrier either a preparation of eukaryotic or prokaryotic cells having signal-generating metabolic activity. 
     
     
         25 . The assay reagent of  claim 24 , wherein the preparation of cells is immobilized onto a particulate carrier. 
     
     
         26 . An assay kit comprising the assay reagent of  claim 24  and containers for contacting the assay reagent with an analyte. 
     
     
         27 . The assay kit of  claim 26  wherein the assay reagent comprises a preparation of cells that has been freeze-dried as a mixture with a carrier, and which kit further comprises a reconstitution buffer suitable for resuspending or reconstituting the freeze-dried assay reagent.