A method is disclosed for improving the efficiency of producing chitin and chitosan, particularly biocompatible chitosan. According to the present invention, there is provided a method of analyzing double stranded DNA present in an analyte, which comprises the steps of: contacting the analyte with a double stranded DNA recognizing substance immobilized on a support, and measuring double stranded DNA bound to the double stranded DNA recognizing substance. An example audio device contains a channel selector, a control interface, and an audio interface. Alternatively, the notification may include recognizing the storage being freed and communicating the recognition to the storage device. The outer sensing region, disposed on the sensing panel, is at the outer edge of the inner sensing region.