A lid for a well plate is provided. Pins penetrate the lid and project downwardly into the wells of the well plate. Thermal energy is applied to the upper end of the pin to regulate the temperature of liquid samples in the well plate. Ultrasonic energy is applied to the upper end of the pin to sonicate the liquid sample. An electrical charge is applied to the upper end of the pin to attract charged materials, such as DNA, and to selectably segregate charged materials from the liquid sample.