A cushion clip may include a cushioning portion made of a soft material and capable of being elastically deformed when a compression force is applied thereto, an attachment portion made of a hard material, and a connecting portion integrally formed with the attachment portion. Methods of forming vesicles and methods of delivering nucleic acid, in particular, iRNA into cells, are also provided. The system further comprises one or more programming objects, such as RFID cards, by means of which a time schedule can be programmed in the controller, the programming object being removable from the controller during its normal operation.