Prof. Yang Sung develops high sensitivity anthrax detection technology

 

- Raised detective function of electrochemical sensor by making use of affordable and stable artificial peptide –

 

 

 

 

 

The joint research group between GIST (Gwangju Institute of Science and Technology, President žYoung Joon Kim) and Caltech successfully developed a small-sized electrochemical sensor to detect protein formed in response to anthrax infection to a minimal concentration level in a short span of time. The sensor is expected to be useful in anthrax detection and infection diagnosis.

 

This research was conducted by a team of Korean researchers led by Prof. Yang Sung of GIST’s Medical System Engineering Dept. and School of Mechatronics and a team of US researchers led by Prof. James R. Heath of Caltech, with sponsorship of the Senior Researchers Support Project (take-off research) co-administered by the Ministry of Science, ICT and Future Planning and Korea National Research Foundation. Their research findings were published by the on-line edition of ACS Nano, an international Nano science journal, on September 24.

 

(Title of paper: A Chemically Synthesized Capture Agent Enables the Selective, Sensitive, and Robust Electrochemical Detection of Anthrax Protective Antigen)

 

The initial symptoms of anthrax infection are similar to the general symptoms of infective respiratory diseases such as pneumonia, but gradual spread of toxin in the body leads to death. That’s why early diagnosis is crucial for anthrax treatment.

 

However, existing sensors were too sensitive to temperature and had only limited sensibility since they used antibody* to detect the concentration level of anthrax protective antigen** which is manifested from anthrax bacteria once a human body is infected by anthrax.

 

* Antibody: Immune protein formed in response to a particular antigen and whose structure easily changes when affected by heat and acidity.

 

** Protective antigen: one of toxins manifested from anthrax bacteria in an anthrax-infected human body, and protective antigen itself is taken as a diagnostic sign of anthrax infection.

 

As an alternative, an ultra-sensitive anthrax sensor was made by laying peptide which was developed by Caltech researchers and selectively captures protective antigen on the surface of gold Nano-particles developed by GIST researchers.

 

The sensor is capable of detecting protective antigen at as low concentration as approx. 2pM which is 500 times the sensitivity of anthrax diagnostic value suggested by DARPA.

 

Gold Nano-particles were sprayed on gold electrodes, thus expanded the surface space by 6 times and raised sensitivity.

 

In addition, the sensor used synthetic peptide which has a relatively simple structure instead of complex-structured antigens, and hence is less prone to change regardless of temperature, making itself a more advantageous option for field application.

 

Prof. Yang said “The ultra-sensitive anthrax sensor uses highly selective and reliable peptide to detect anthrax protective antigen and hence is expected to become a useful tool to diagnose anthrax infection.”