Method of storing tetrazolium compound, stabilizer for use therein, and tetrazolium compound reagent solution stored by the method

Abstract

A method for storing a tetrazolium compound stably is provided. The tetrazolium compound is stored in the presence of sodium azide. The tetrazolium compound (A) and the sodium azide (B) are present at a ratio (A:B) in the range from 1:0.02 to 1:6.2. Furthermore, when the tetrazolium compound is stored as a solution, the concentration of the sodium azide is in the range from 0.08 to 3.2 mmol/L and the concentration of the tetrazolium compound is in the range from 0.5 to 8 mmol/L. As the tetrazolium compound, it is preferable to use 2-(4-iodophenyl)-3-(2,4-dinitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium salt.

1 . A method for storing a tetrazolium compound stably, comprising: 
 storing the tetrazolium compound in the presence of sodium azide.    
     
     
         2 . The method according to  claim 1 , wherein the tetrazolium compound (A) and the sodium azide (B) are present at a ratio (molar ratio A:B) in a range from 1:0.02 to 1:6.2.  
     
     
         3 . The method according to  claim 1  or  2 , wherein the tetrazolium compound and the sodium azide are present in a solution, and a concentration of the tetrazolium compound is in a range from 0.5 to 8 mmol/L.  
     
     
         4 . The method according to any one of  claims 1  to  3 , wherein the tetrazolium compound and the sodium azide are present in a solution, and a concentration of the sodium azide is in a range from 0.08 to 3.2 mmol/L.  
     
     
         5 . The method according to  claim 3  or  4 , wherein a pH of the solution is in a range from 5.0 to 7.5.  
     
     
         6 . The method according to any one of  claims 1  to  5 , wherein the tetrazolium compound is 2-(4-iodophenyl)-3-(2,4-dinitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium salt.  
     
     
         7 . The method according to any one of  claims 1  to  6 , wherein a storage temperature is in a range from 4° C. to 60° C.  
     
     
         8 . A stabilizer for storing a tetrazolium compound stably, comprising sodium azide.  
     
     
         9 . A reagent solution comprising an aqueous solvent and a tetrazolium compound dissolved in the aqueous solvent, wherein sodium azide further is dissolved in the aqueous solvent.  
     
     
         10 . A dry reagent containing a tetrazolium compound, obtained by drying an aqueous solvent in which the tetrazolium compound and sodium azide are dissolved.