Kyoto, Japan, November 14, 2001--- The Biomedical Group of Takara Shuzo Co., Ltd. announced today that the scientists had developed new diagnostic reagents that could be used to detect a target DNA amplified by the Group's original technology, ICAN method. The diagnosis can be achieved by detecting an amplified DNA of target on a paper strip with the original contrivance. Diagnostic items developed this time include the reagents to detect Mycobacterium tuberculosis, Chlamydia, and Neisseria gonorrhoeae. The diagnosis can finally produce a visible result as a red line on the test paper, if there are the infectious microorganisms in a sample. The target DNA amplification by ICAN method and the detection with the test paper can be completed in 90 minutes without a special instrument, so the bedside diagnosis can be realized by the combination.

Principle of the detection
A target DNA in a sample is amplified by ICAN method, followed by hybridization with a specific probe. The complex is spotted on a lower position of the paper strip and the end of the strip is dipped in a liquid reagent. The complex is moved to upper side by liquid absorption and is captured at the position where a special reagent was immobilized to produce a red line as a result. When there is no target DNA in a sample, the red line is never appeared.

Advantages of this system
At present, polymerase chain reaction (PCR) method is mainly used in diagnostic products to amplify a target DNA in a sample. This method, however, requires a special instrument like a thermalcycler to periodically change temperature. In addition, another instrument is also needed to detect or measure fluorescence or color of the reaction product. Consequently, clinicians cannot use this method at bedside for prompt diagnosis. As the samples are usually transported to professional examination laboratories, it takes 3 to 6 days to obtain results of diagnosis. The combination of ICAN method and the test paper will provide a simple tool for bedside diagnosis, because of no requirement of special equipments and visible results.

Future plans
The researchers are now developing diagnostic kits for simultaneous detection of multiple pathogens such as Chlamydia and Neisseria. In addition to the clinical purposes, the elegant technology can be applied to other purposes in areas of food, environment and animal testing, which require measurements in the field. A detection kit for anthrax will also be developed before long.

This article is translated from press release in Japanese for your convenience.