Figure 3
From: Ultrafast photonic PCR
LED-driven photothermal heating of the thin Au films and PCR thermal cycling. (a) Absorption spectra of the thin Au films with different thickness. Absorption (%)=100–Transmittance (%)–Reflectance (%). Temperature profiles of liquids (b) as a function of Au film thickness with a 500 mA injection current and (c) as a function of the injection current of the LEDs using a 120-nm-thick Au film. The blue LED with a 450 nm peak wavelength was used. (d) Two-dimensional map showing the distribution of liquid temperatures with different thicknesses of the thin Au film and injection currents of the LEDs after heating for 3 min. (e) Demonstration of LED-driven photonic PCR thermal cycling, consisting of three different temperatures; 94 °C (denaturation), 60 °C (annealing) and 72 °C (extension). (f) Accurate temperature control and low temperature variation for PCR thermal cycling. The average values with standard deviation at 94 °C, 60 °C and 72 °C were 94.09±0.17 °C, 59.94±0.13 °C and 72.02±0.12 °C, respectively. LED, light-emitting diode; PCR, polymerase chain reaction.
