Tip Enrichment System for Rapid Screening of Mycobacterium Tuberculosis

Rapid detection of tuberculosis (TB) has been critically demanded over the last century. To detect TB, numerous methods screening Mycobacterium tuberculosis (MTB) have been developed. However, the methods still have challenges of rapid and specific enrichment of MTB. In this study, we present a novel specific enrichment method of MTB using a microfabricated tip. Through our simulation study, a wavy-shaped microtip is designed to enhance capturing efficiency of bacteria. Using an optimized tip, bacteria are attracted by dielectrophoresis and captured by affinity binding and capillary action. In experiment, a surrogate marker of MTB, Bacilli Calmette-Guerin (BCG), is enriched with the micromachined tip. When a microtip decorated with capturing antibodies is used, BCG cells spiked in saliva are detected at the concentration of 5×10⁵ CFU/mL within 20 minutes. The tip enrichment system demonstrates the potential for rapid, culture-free detection of MTB in a raw sample.