Methods of determining active levels of drugs in fluid samples

Abstract

Methods for determining the presence and level of active drugs in fluid samples are provided. Advantageously, entire families or classes of drugs can be tested for in one test by identifying the enzyme or receptor upon which members of that drug family act and measuring enzyme activity levels or binding activity levels of receptors. Methods for establishing standard activity levels of these drugs based upon results from samples having known quantities of drug therein are also provided.

We claim:  
     
         1 . A method of determining standard enzyme activity levels on a selected substrate comprising the steps of: 
 providing a sample containing said enzyme;    adding a known quantity of said selected substrate to said sample;    measuring the activity level of said enzymes on said selected substrate; and    using said measured activity level as said enzyme's standard activity level for said known quantity of selected substrate.