ug A majority of biomaterials used for drug delivery systems have release profiles which begin with a quick burst of the drug followed by a gradual decrease in the release rate overtime as seen in the figure below. One way to model the amount of drug released is assume a linear profile for the initial burst and an exponential decay for the latter portion. For a specific biomaterial the initial rate of drug release is 66.7 t for the first 36 hours and day2 the following profile is 150 ug e 3.7days. day Assume that a this biomaterial is implanted in the cartilage of the knee, if the initial amount of drug is 700ug what amount of drug left in the biomaterial after 15 days? -t . ug release = 66.7 t day2 Drug release (ug/day) releasez ug 150 3.7days . e day Time (hrs) 36 hrs