Method for immobilizing protein a on a self-assembled monolayer

Abstract

The object of the present invention is to provide a method for increasing an amount of Protein A to be immobilized on the self-assembled monolayer. Immobilizing Protein A to the self-assembled monolayer through the structure represented following formula (II) obviates the object.

1 . A method for detecting or quantifying a target substance contained in a sample with a sensor, comprising the following steps (a) to (c) in this order,
 a step (a) of preparing the sensor comprising a self-assembled monolayer, a one molecule of the amino acid, a Protein A, and an antibody, wherein,   the one molecule of the amino acid is interposed between the selfassembled monolayer and the Protein A,   the Protein A is interposed between the antibody and the one molecule of the amino acid, the antibody is bound specifically to the target substance,   the Protein A is bound to the self-assembled monolayer through two peptide bonds represented by the following chemical formula (II),   
       
         
           
           
               
               
           
         
         wherein R represents a side chain of one molecule of the amino acid, the one molecule of the amino acid is selected from the nineteen kinds of amino acids consisting of cysteine, lysine, histidine, phenylalanine, tyrosine, glycine, asparagine, methionine, serine, tryptophan, leucine, glutamine, alanine, isoleucine, threonine, proline, glutamate, aspartate, and valine, 
         a step (b) of supplying the sample to the sensor to cause the target substance to be bound to Protein A, and 
         a step (c) of detecting or quantifying the target substance contained in the sample from the captured target substance or the amount thereof. 
       
     
     
         2 . A method according to  claim 1 , wherein the chemical formula (II) is represented by the following chemical formula (III), 
       
         
           
           
               
               
           
         
         wherein R represents a side chain of one molecule of the amino acid. 
       
     
     
         3 . A method according to  claim 1 , wherein the one molecule of the amino acid is selected from the group consisting of cysteine, lysine, histidine, phenylalanine, tyrosine, glycine, asparagine, methionine, serine, tryptophan, leucine, glutamine, alanine, isoleucine, threonine, proline, glutamate, and aspartate. 
     
     
         4 . A method according to  claim 1 , wherein the one molecule of the amino acid is selected from the group consisting of cysteine, lysine, histidine, phenylalanine, tyrosine, glycine, asparagine, methionine, serine, tryptophan, leucine, glutamine, alanine, isoleucine, and threonine. 
     
     
         5 . A method according to  claim 1 , wherein the one molecule of the amino acid is selected from the group consisting of cysteine, lysine, histidine, phenylalanine, tyrosine, glycine, asparagine, methionine, serine, and tryptophan. 
     
     
         6 . A method according to  claim 1 , wherein the one molecule of the amino acid is selected from the group consisting of cysteine, lysine, histidine, phenylalanine, and glycine.