Handheld battery-operated sample preparation device for qPCR nucleic acid detections using simple contactless pouring

[摘要] Sample preparation is an essential process that precedes nucleic acid detections which use quantitative polymerase chain reaction (qPCR). However, sample preparation is a labor-intensive process and requires skilled labor, thus limiting the public's access in low-resource settings to many high-quality nucleic acid-based detection mechanisms. In this paper, we present a simple, handheld, battery-operated sample preparation device to minimize user's involvement. The device uses a simple pouring method to process the DNA sample without pipetting or using disposable pipette tips. The developed device has a size of 12 × 8 × 8 cm3 and mass of only 364 g. The device is compared to gold standard methods, including magnetic bead-based and silica filter-based DNA extractions. For a short segment DNA target of 68 bp, the presented device captured 8.67× more DNA compared to that of the manual magnetic bead-based method. Because of automation, the measured capture efficiency is more consistent and has a smaller deviation between multiple repetitions than the manual method. To present a comprehensive, portable, battery-operated diagnostic system, the sample preparation device is tested in conjunction with a 3D-manufactured qPCR device. The test using three diluted target DNA samples, each spiked in whole blood (1×, 0.1×, and 0.01×), revealed a quantitative detection with ideal cycle threshold separations between the measurements. The combination of two devices will aid in resource-limited settings to promptly and accurately diagnose infections of patients.

[学科分类] 分析化学