Size Exclusion Chromatography (SEC) was employed to separate DNA fragments in the buffer near physiological conditions so that the attributes and activeness of DNA was best maintained. DNA mixture at ppm level in this kind of buffer was spiked with either uranium or holmium at low ppb level. The amount of metals bound to DNA was quantified by ICP-MS over time. The sizes of DNA fragments interacting with metals were determined by SEC. Putting SEC and ICP-MS in line made the dynamic investigation on kinetics of DNA-metal interactions possible. Uranium was chosen for this research due to its importance in industry and military and its widespread occurrence in our surroundings. Holmium was picked because of the chemical similarity between lanthanide elements and post-uranium actinides elements and the low radioactivity of holmium. ICP-MS was also used to quantify the phosphorous of phosphoprotein. It turned out the phosphorous of proteins can be determined by ICP-MS plus inorganic phosphorous reliably and accurately. The detection limit of phosphorous was as low as 8 pg if the spectrum method was in use and it was as low as 20 pg if the flow injection method was in use.