We present a system comprised of a PDMS microfluidic device and an injection system for dilution of DNA derived from whole blood to a single strand. We discuss two microfluidic architectures for ultra-high ratio dilution (1:1000 or more) as well as the necessity to move beyond previously reported dilution architectures. We describe a custom injection system used both for fabrication and operation of the system. The system is operated by placing syringes, one filled with water and one filled with DNA extracted from whole blood, into the injection system. This system fixes and plunges the syringes simultaneously to introduce both solutions into the microfluidic channels that produce the ultra-high ratio dilutions. The most significant constraint on the design is that the system is designed for fabrication, characterization and use in a clinical setting.