| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a DNA measurement apparatus capable of carrying out a real-time measurement in a total electronic fashion as to existence of hybridization and extension reactions of a target DNA and a DNA probe. <P>SOLUTION: An insulated gate field effect transistor 4 is provided wherein the DNA probe 12 is immobilized on a gold electrode 11, and an extension reaction is carried out on the gold electrode by using a DNA polymerase, and phosphoric acid, i.e., negative charge increased by the extension reaction is measured directly from changes in current flowing through a source 13 and a drain 14 of the insulated gate field effect transistor 4, thereby detecting the existence of hybridization and extension reactions of the target DNA and the DNA probe 12. The immobilization density of the DNA probe 12 on the gold electrode is optimized to 4×10<SP>12</SP>number/cm<SP>2</SP>. Furthermore, a high-frequency voltage of 1 kHz or more is applied across the gold electrode 11 and a reference electrode 5 by using a power supply 6, in order to reduce instability of a surface potential which is caused by external fluctuations (influences of foreign substances and the like) and poses a problem when using the gold electrode 11 in a solution. <P>COPYRIGHT: (C)2007,JPO&INPIT |
