METHOD FOR SUPPRESSING FORMATION OF ADAPTER DIMER

To provide novel methods and kits for suppressing the formation of adapter dimer, in a method and the like for preparing a nucleic acid library that can be used for sequence analysis with NGS.SOLUTION: The present invention provides a method and the like for suppressing the formation of adapter dimer by increasing the concentration of the buffer in the reaction solution used for terminal repair and terminal adenylation reactions. In a particular embodiment, the present invention provides a method for suppressing the formation of adapter dimer, the method including the following steps: (A) subjecting the nucleic acid fragment to a terminal treatment by coexisting a buffer solution of 100 mM or more in a reaction solution for performing the terminal repair of the nucleic acid fragment and/or the terminal adenylation of the nucleic acid fragment; and (B) reacting the nucleic acid fragment treated in the step (A) with an adapter...