HIGHLY SENSITIVE AND SPECIFIC MICROTIP-IMMUNOFLUORESCENCE SENSOR FOR RAPID TB DIAGNOSIS

摘要

A microtip-immunofluorescence sensor enables the detection of Mycobacterium tuberculosis complex cells in sputum in 25 minutes. Three concentration mechanisms based on flow circulation and electric field are combined at different scales to concentrate target bacteria in 1 mL samples onto the surfaces of microscale tips. Specificity is conferred by genus-specific antibodies on microtip surface in combination with the capillary-induced capture when the microtip is withdrawn from the sputum. Immunofluorescence is then used to detect the captured cells on the microtip. The detection limit in sputum is 200 cfu/mL, which is equivalent to a PCR method.