About This Project

M. tuberculosis is slow growing pathogen, TB in early infection is difficult to diagnose correctly, so culture is the WHO-recommended gold standard for TB diagnosis, but it may take more than 1 to 3 months. The patient may inadvertently become a spreader while waiting for the results. We propose a solution using Raman spectroscopy that can detect pathogen more accurate than the current test. If our results are positive, we should be able to early detect and treat TB to prevent spread of disease.

Ask the Scientists

What is the context of this research?

In recent years, the application of Surface enhanced Raman scattering (SERS) as a detection platform is more popular1 2, SERS so that the weak Raman signal enhanced 10¹¹ times. we proposal the strategy consists of two phases: (i) Antibody or aptamer conjugated nanoparticles as probe, that can capture and concentrate the pathogen protein form the sputum sample, antibody can concentrate and confirm the pathogen specificity, and (ii) Raman spectrometer scanning Raman tag on nanoparticle surface. SERS technology can amplify Raman tag signal to 10¹¹ times. Therefore, we are able to detect TB in the pathogen is very rare period. By developing the Raman-based system to detect a particular target protein, we can potentially adapt this technology to diagnose a particular disease.

What is the significance of this project?

M. tuberculosis grows slowly. In the early stages of infection, the number of bacteria is very small so it is difficult to diagnose the disease. Traditional diagnosis (Smears Acid-Fast bacillus staining) needs 1 to 3 months to culture and is very time consuming. As a result, TB in early infection is difficult to diagnose correctly. We are proposing may be able to accurately detect tuberculosis early in infection. If the results are successful, it can become an important tool for prevention and treatment of tuberculosis. Our design provides a cheap, sensitive, accurate, and rapid diagnostic tool that can effectively prevent the spread of tuberculosis. Additionally, our detection model can theoretically be adapted to detect any particular target, allowing expansion to detect other diseases.

What are the goals of the project?

After infection, M. tuberculosis will secrete many proteins into the sputum and blood, such as Ag85b, ESAT-6, CFP-10 and so on. In early infection, the bacteria is rare, but it still will secrete a lot of ag85b protein into the sputum and blood, so our method is to use an anti-ag85b antibody conjugated Fe2O3 nanoparticles, and then another anti-Ag85b aptamer conjugated Au NP, which also conjugated DTNB. We plan to add the antibody–Fe NP and aptamer–Au NP-DTNB into sputum , after the magnet aggregates and then use the spectrometer to detect the Raman signal of the DTNB. We combine specificity of antibodies and sensitivity of SERS . The model can be applied to any antigen, thus making a detection system that will work for a multitude of diseases.