Journal: Science Advances

Article Title: Innovative qPCR using interfacial effects to enable low threshold cycle detection and inhibition relief

doi: 10.1126/sciadv.1400061

Figure Lengend Snippet: ( A ) The DOTS qPCR device showing all components: semicircular channel with PID-controlled heaters positioned at both ends, feedback thermocouples mounted 5 mm above the heater surface, motor arm with looped thermocouple mounted for droplet suspension in heated oil, viewing window at the center of the channel, and lens tube to focus and magnify the droplet image onto the smartphone camera. All components are disposable after one use except for the motor, lens tube, and smartphone. ( B ) Alternate view showing the DOT moving to the low-temperature side of the heat gradient. ( C ) Two thermocouples mounted on the motor arm. The straight thermocouple is used for oil temperature measurement, and the looped thermocouple holds the droplet and measures the droplet temperature. ( D and E ) Still images of the submerged droplet moving back and forth continuously at the low-temperature region. The thermocouple junction is inside the droplet to monitor the reaction temperature. Droplet temperature feedback is used by the motor program to accurately position the droplet in the heat gradient. The still images are screen captures from the supplementary video showing device operation (movie S3). ( F ) Still image of the droplet moving away from the low-temperature region after completing annealing, to be positioned at a warmer region corresponding to the optimum temperature for Taq polymerase extension of the PCR amplicon.

Article Snippet: The standard PCR cocktail is composed of the following components: PCR Master Mix [GoTaq Green Master Mix 2X (Promega, M7122), GoTaq Colorless Master Mix 2X (Promega, M7132), or Fast SYBR Green Master Mix 2X (Applied Biosystems, 4385612)]; forward and reverse primers (10 μM); target; and nuclease-free water in the proportion 5:1:1:3.

Techniques: Suspension, Amplification