University of Pittsburgh researchers have designed and built a rapid, affordable, and reliable tuberculosis (TB) diagnostic tool. Using semiconducting single-walled carbon nanotubes (SWCNT)-functionalized with an antibody-antigen, a field effect transistor (FET) nanobiosensor has been produced which successfully detects TB with high sensitivity in artificial sputum and human blood serum.
Using semiconducting SWCNT-functionalized with an antibody have been developed to detect the major MTB-secreted antigen 85B and allows for rapid and effective detection of TB.
Description
TB is the second leading infectious disease killer after COVID-19 and ending the global TB epidemic by 2030 is one of the UNﾒs Sustainable Development Goals. Caused by mycobacterium tuberculosis (MTB), TB is a highly contagious airborne disease that spreads when a patient coughs, speaks, or sneezes. There are two clinical classifications of TB, active (symptomatic and infectious) and latent, where concentrations of MTB are too low to show symptoms. The CDC estimates that 13 million people have latent TB in the USA which, if left untreated, can develop to active TB. Early diagnosis is key to the prevention of active TB and further spread, but current diagnosis can be costly and unattainable in low resource developing countries where TB remains a leading cause of morbidity and mortality. This novel fast, efficient, and inexpensive diagnostic tool could aid the global fight against TB.
Applications
• Mycobacterium tuberculosis
Advantages
Currently, TB diagnosis methods include chest X-rays, detection of bacilli by microscopic techniques and bacterial growth cultures, detection of host immune response to the pathogen (i.e., Mantoux test), bacterial nucleic acid amplification method, and interferon-g release assays. However, all have short comings including low sensitivity to latent TB (chest X-rays) the need for time and accuracy which depends on previous vaccinations (Mantoux), or assays that require specialized equipment or reagents which increase costs and are a barrier to their widespread use, especially in developing countries. This novel diagnostic tool is designed to provide rapid, simple, effective TB detection allowing for extensive use, especially in low resource settings. This FET-based device requires only small samples and has high sensitivity with a limit of detection (LOD) in the region of 1 fg/mL, like that of PCR with none of the time or resource requirements of PCR.
Invention Readiness
A prototype SWCNT-based FET device has been built. The SWCNT was functionalized with an antibody to detect the major MTB-secreted antigen 85B. Fabricated from commercially available economical semiconductor-enriched SWCNTs, this FET device has a high on/off ratio of ~104. The devices were found to detect MTB in spiked phosphate-buffered saline (PBS), artificial sputum, and serum samples within 10 minutes with LOD of ~1 fg/mL with high specificity and a large dynamic range. These sensors could provide rapid, accurate, and low-cost TB diagnosis.
IP Status
https://patents.google.com/patent/WO2025042890A1
