A Molecular Computing Model for Graph Coloring Problem Using DNA Quantum Dot

We present a computing model using DNA/QD (quantum dot) conjugates to solve a graph coloring problem. In this model, an effective DNA strand displacement and specific sequence recognitions ensure the accuracy of constructing the initial solution space and deleting the false solutions. The DNA/QD conjugates play a key role in obtaining the true solutions through electrophoresis. Because the process is enzyme-free, the biological operation is fast and only needs to be carried out once to eliminate false solutions and gain the optimum solution. Compared with conventional algorithms, its time and space complexity is much lower owing to the high parallelism of molecular computing.