Fig. 1.

Single-cell genome amplification device. (A) Photograph of a single-cell isolation and genome amplification chip capable of processing eight samples in parallel. To visualize the architecture, the channels and chambers have been filled with blue food coloring, and the control lines to actuate the valves have been filled with red food coloring. (Scale bar, 5 mm.) (B) Schematic diagram of a single amplification unit. The feed line is used to bring reagents into the chambers when the V_R valve is open and to the waste when the V_w valve is open. The V_in valve allows deposition of a single bacterium into the sorting chamber. The lysis (3.5 nl), neutralization (3.5 nl), and reaction chambers (50 nl) are used in sequence and are separated by individual valves V_L, V_N, and V_R, respectively. Valve V_out allows recovery of the amplified genomic material from the chip into an individual microfuge tube. (C) After a cell is trapped in the chamber, the feed line is filled with lysis buffer. (D) The lysis buffer is used to push the cell into the lysis chamber. (E) While the lysis buffer is mixing with the cell solution by diffusion, the feed line is flushed. (F) Neutralization buffer is loaded into the feed line and used to push the cell lysate into the neutralization chamber. (G) While the neutralization reaction is mixing by diffusion, the feed line is flushed. (H) The WGA reagents are loaded into the feed line and used to push the neutralized cell lysate into the reaction chamber. (I) The amplification reaction proceeds in a closed system comprising sorting, lysis, neutralization, and reaction chambers.