Advances on Electrochemiluminescent Biosensors for TB Biomarkers

Tuberculosis (TB) is a highly contagious bacterial infection that remains a leading cause of death and persistent threat to global health. The spread of TB is exacerbated by the major limitations of conventional diagnostic approaches, such as complex technicalities, high cost, and low sensitivity. To address these challenges, recent research has focused on using electrochemiluminescence (ECL) as an alternative detection strategy coupled to biosensors. ECL biosensors leverage electrochemically generated chemiluminescence, converting electrical energy to light, as a novel transduction mechanism for TB biosensors. This unique approach offers several advantages, namely, wide linear dynamic ranges, improved device sensitivities, and prompt response times for sensitive early detection. This Review offers a comprehensive overview of advancements in ECL biosensor configurations, including detection and amplification strategies, substrates, and the development of luminophores and coreactants tailored for TB biomarker detection. The focus is on ECL biosensor designs, including biorecognition elements like immunosensors, DNA sensors, and aptasensors, along with various immobilization strategies tailored to target specific TB biomarkers. A comprehensive discussion spans biomarker detection trends over the past decade, clinical relevance, sensitivity thresholds, and detection limits. Furthermore, widely recognized TB biomarkers commonly detected in commercial diagnostic tests are discussed alongside novel markers that, while not exclusive to TB, have demonstrated clinical importance. This Review aims to highlight the potential of ECL-based biosensors as an effective means to advance an early, reliable, and accessible TB detection approach.