Apparatus for supporting an array of layers of amphiphilic molecules and method of forming an array of layers of amphiphilic molecules

A method of preparing an apparatus for forming an array of layers of amphiphilic molecules, the method comprising:

• providing an apparatus comprising a body, and, formed in a surface of the body, an array of wells, at least some of which are sensor wells capable of supporting a layer of amphiphilic molecules across the sensor wells after application to the sensor wells of a pre-treatment that is a fluid capable of interacting with the amphiphilic molecules, the sensor wells each containing an electrode for connection to an electrical circuit, and
• delivering across the surface of the body a pre-treatment, that is a fluid capable of interacting with the amphiphilic molecules, in a solvent to apply the pre-treatment to the wells;
• and
• drying the surface of the body to remove the solvent under a pressure below atmospheric pressure;
• wherein the method is performed so that each of the following conditions is met:
• visible coverage of the surface by the pre-treatment is less than 15% of an area in which the array of sensor wells is located;
• a proportion of sensor wells that are filled is less than 5%;
• and
• values of rectangularity and a perimeter of all annuli of pre-treatment around the respective sensor wells falls within 40% of average values.