Reagent kit for detecting biofilm and method for detecting biofilm

A method for detecting the presence of biofilm in test tissue, comprising the following steps 1 to 4:

• (1) step 1 of bringing a membrane capable of adsorbing biofilm and/or components thereof into contact with test tissue;
• (2) step 2 of releasing the membrane from contact with the test tissue, and then treating at least the contact surface of the membrane with the test tissue with (a) a pretreatment liquid comprising at least one surfactant selected from the group consisting of nonionic surfactants, amphoteric surfactants, and cationic surfactants;
• (3) step 3 of treating, with (b) a staining liquid comprising a dye, at least the contact surface with the test tissue of the membrane treated with the pretreatment liquid (a);
• and
• (4) step 4 of treating, with (c) a decolorizing liquid comprising at least one surfactant selected from the group consisting of nonionic surfactants, amphoteric surfactants, and cationic surfactants, at least the contact surface with the test tissue of the membrane treated with the staining liquid (b).