Fabrication of a novel radiopharmaceutical: lutetium-177 loaded MCM-41mesoporous silica

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Targeted therapy of cancer, by binding the radionuclide with a carrier agent, provides more accurate delivery to focal tumor cell with low uptake in normal organs. In this paper, a new radio-loaded nanoparticle has been explored. A method for loading [superscript 177]Lu into MCM-41 was evaluated by varying starting material and loading reaction factors. For the procedure of [superscript 177]Lu loaded MCM-41, cetyltrimethylammonium bromide was dissolved in a solution of 384 ml of MilliQ water heated at 45[degree sign]C and then 2 M NaOH aqueous solution was added. The mixture was stirred vigorously at 80[degree sign]C for 0.5 h. Then tetraethylorthosilicate was added dropwise with vigorous stirring for another 2 h, followed by filtration and drying in the oven at 100 [degree sign]C for 12 h. Grounded powder was calcined in furnace at 550 ?C for 5 hours to remove the surfactant. And then MCM-41 solution was prepared by its fine powder in MilliQ water to give a concentration of 50 mg/ml. The reaction mixture consisted of a 150 [micro]l aliquot of the stock solution containing 20 [micro]g MCM-41(0.2669 mmol) and 150 [micro]l of [superscript 177]LuCl[subscript 3] solution (76.5 MBq) to which was then added 500 [micro]l of 0.01 M LaCl3 ?5 ?mol) mixed at room temperature and then 1 M NaOH was added to reach pH =6.5 for 1 hour. This novel synthesis method shows an over 99 % loading percentage of [superscript 177]Lu-MCM-41.