The versatility of DNA as a reversible materials assembly tool has been demonstrated by several past studies using changes in temperature. We are interested in extending DNA as a tunable and reversible biomaterials assembly tool and are thus limited to fixed salt concentration and temperature conditions. Specifically, we are investigating using primary hybridization events between immobilized complementary DNA sequences to assemble a model multiparticle drug delivery vehicle. In order to release particles from the assembly once delivered to the targeted tissue, we rely on secondary or competitive hybridization events to displace duplexes linking complementary particle surfaces. Our current focus involves studying the effects of DNA sequence length and concentration on the kinetics of competitive hybridization events to control the timing of particle release. We quantify both the number of displaced soluble target strands and the extent of disassembly of DNA-linked colloidal satellites. Using flow cytometry, we have found that the kinetics of competitive displacement depend strongly on the overall target length, the differences in length of the primary and competitive targets, and the concentration of competitive targets. We find that the kinetics of competitive displacement of soluble targets are on the order of minutes whereas disassembly of DNA-linked colloidal satellites requires several hours and even days. In addition, the kinetics of particle release from assemblies appears more sensitive to sequence characteristics. Through careful choice in sequence length and concentration, we propose that DNA provides a unique recognition-based tool to program the assembly and disassembly over a large time-scale for biomaterials applications ranging from drug-delivery to degradable scaffolds.