Rapid screening of Mycobacterium tuberculosis complex (MTBC) in clinical samples by a modular portable biosensor

Mycobacterium tuberculosis complex (MTBC) is the well-known causative agents of tuberculosis (TB). Transmission of bacteria via airborne routes makes infection control difficult. Hence, rapid and accurate identification of TB from clinical sputum samples is essential for minimizing the spread of the disease. However, traditional bacterial identification methods for TB are time consuming and labor intensive. The aim of this study is to propose a straightforward and rapid screening platform for MTBC using a portable organic light-emitting diode- (OLED-) based surface plasmon resonance (SPR) biosensor integrated with a nested PCR technique. Experimentally, the limit of detection (LOD) for MTBC PCR products measurement was estimated to be around 63 pg/mL. In addition, the biosensor can successfully differentiate MTBC from other nontuberculous mycobacterium strains. In 600 clinical sputum specimens, the sensitivity and specificity were 96.6% (86/89) and 98.4% (503/511), respectively. These results indicate that the portable OLED-based SPR biosensor may be taken into account as a suitable and convenient tool employed in the remote area and developing country for diagnosing TB diseases.