Surface modification of a polymeric contrast agent for cancer targeting

In order to develop a targeted contrast agent that enhances ultrasound images, polylactic acid (PLA) microcapsules were coated with fibronectin peptide sequences. The microcapsules were coated with either GRGDS or REDV peptide sequences that target integrins expressed in angiogensis, /spl alpha//sub v//spl beta//sub 3/ and /spl alpha//sub v//spl beta//sub 5/. Preliminary in vitro (static and flow regimes) results indicate that the modified capsules remain highly echogenic and adhere to the breast cancer cell line MDA-MB-231 as opposed to unmodified control capsules. Specific targeting of ultrasound contrast agents could be used as a means of targeted imaging for tumor cells and potentially as a drug delivery vehicle.