Master of Science
Walter Henne, Jr., Ph.D.
Joseph B. Addison, Ph.D.
Aheda Saber, Ph.D.
Folate receptor is a membrane bound protein which is highly expressed by cancer cells and macrophages. Folic acid is required for the normal growth of cells and it has been found that rapidly growing cancer cells require high levels of folic acid. Folic acid binds to folate receptors and through receptor mediated transport folate enters cells. This property has been used to synthesize a probe using folate as ligand through polyethylene glycol-Biotin linker. This can be used to attach a drug which is ultimately delivered at the site of infectious cells. The study involved here was to determine how folate and magnetic beads can be used to develop imaging systems and transport drugs to identify and treat pathologies. Folate-PEG-Biotin probe (already synthesized from Dr. Walter Henne and Mr. Rohan Patel) was purified by HPLC and LC/MS which was then used to perform cell binding studies with streptavidin coated magnetic beads on L1210 type cancer cells. Biotin which is a B-complex vitamin is also required for the growth of cells. This biotin has the highest non-covalent affinity to streptavidin in nature and hence was used to link streptavidin coated magnetic beads to folate. Polyethylene glycol was used as a spacer. This streptavidin protein in the form of magnetic beads captures cells from solution when used with the Folate-PEG-Biotin probe. Cells were observed under a high resolution light microscope and the images were taken with a high resolution camera available from Dr. Tim Gsell’s laboratory. Cells were also studied by just adding streptavidin beads alone to observe if they were captured. To another control, Folate-PEG-Biotin/Streptavidin coated magnetic beads were added along with 1000 fold excess of folic acid.
This method is economical and can be used to replace other cancer cell detection techniques. Future studies include the conjugation of folate-peg-biotin probe with a proprietary drug conjugate to determine the drugs activity on cancer cells which will be carried out at Purdue University.
Vanga, Kuldeep Reddy, "Evaluation and In Vitro Studies of Folate-PEG-Biotin" (2011). All Capstone Projects. 64.