Designing point-of-care (POC) molecular diagnostics systems that are accurate but also easy-to-use, portable, and cost-effective is challenging. In a recent article in Biosensors and Bioelectronics, Shu and colleagues described their battery-powered, pocket-sized, closed-loop convective PCR device, which integrates both sample preparation and product detection.
First, a bacterial sample is loaded into the capillary tubing. The bacteria bind to vancomycin-modified magnetic beads which are then captured by a magnetic array. Bacterial DNA is released by photothermolysis and vibration. The DNA travels into the reaction loop, a capillary attached to a metal triangular scaffold with a thermal gradient (95 °C at one end and 60 °C at the other). Convective PCR occurs without the need to actively heat and cool the system, during which a wireless fluorescence imaging module monitors the fluorescence of the PCR products. The authors used EvaGreen® dye for detection of PCR amplification in real time.
The authors report that the device has a run time of less than 25 min, and a dynamic range of 106 to 101 DNA copies/μL showing proof-of-concept for accurate, portable and affordable POC diagnostics.
To read the original article, click here.
B. Shu, C. Zhang, D. Xing. A sample-to-answer, real-time convective polymerase chain reaction system for point-of-care diagnostics. Biosensors and Bioelectronics, 2017. DOI: http://dx.doi.org/10.1016/j.bios.2017.06.014
EvaGreen® dye is the only qPCR dye that can be used for both real-time PCR and high resolution melt curve analysis. It also has applications in isothermal DNA amplification, droplet digital PCR and more. In addition, EvaGreen® dye is non-toxic, non-mutagenic, and not hazardous to aquatic life. To learn more about EvaGreen®, click here.