An integrated microfluidic system for early detection of sepsis-inducing bacteria

Since early diagnosis of sepsis may assist clinicians in initiating timely, effective, and prognosis-improving antibiotic therapy, we developed an integrated microfluidic chip (IMC) for rapid isolation of both Gram-positive and Gram-negative bacteria from blood. The device comprised a membrane-based filtration module (90 min operating time), a bacteria-capturing module using a micro-mixer containing magnetic beads coated with flexible neck regions of mannose-binding lectin proteins for bacteria capture (20 min), and a miniature polymerase chain reaction (PCR) module for bacteria identification (90 min via TaqMan (R) probe technology). The filter separated all white blood cells and 99.5% of red blood cells from bacteria, which were captured at rates approaching 85%. The PCR assay's limit of detection was 5 colony-forming units (CFU) per reaction, and the entire process was completed in only 4 h. Since this is far less than that for culture-based approaches, this IMC may serve as a promising device for detection of sepsis.

Automated summary

The study developed an integrated microfluidic chip for rapid isolation of bacteria from blood, aiding in early sepsis diagnosis. The device is efficient with a high capture rate of 85% and the entire detection process can be completed in just 4 hours.