The U.S. Patent and Trademark Office (USPTO) issued an allowable letter on July 21, 2011 for a patent application titled Nanopore structured Electrochemical Biosensors. The inventor is Dr. Ellen Chen. This patent will be issued in January, 2012. The present invention provides a novel biosensor and measuring method. The novel biosensor of the present invention comprises an electrode having a nanopore structured and catalytically active cyclodextrin attached thereto. The biosensor of the present invention has demonstrated robust analytical performance for direct glucose measurement without mediators or without using native enzyme, which is especially beneficial in the hypoglycemia range.