FORMULATION AND CHARACTERIZATION OF MAGNETIC POLYGLUTARALDEHYDE NANOPARTICLES AS CARRIERS FOR POLY-1-LYSINE-METHOTREXATE

Using the statistically optimised method, submicron magnetic polyglutaraldehyde nanoparticles (Fe-PGNP) with free surface carboxylic groups have been synthesized. A model anticancer agent methotrexate (MTX) has been chemically bonded onto the surface of these particles using poly-l-Lysine (PL) as a spacer. The drug release characteristics of the final delivery device, i.e. [Fe-PGNP]-PL-MTX, has been elucidated at 37°C in a medium containing a proteolytic enzyme. Results demonstrate that using particles containing about 8% w/w of Fe3O4, and PL-MTX conjugate constituting 256 μg MTX per mg of PL, almost 50% of the conjugate can be covalently linked onto the carrier surface. Release studies failed to demonstrate the presence of free drug. However it appears that MTX-oligopeptides are released from the carrier as a result of the enzymatic hydrolysis of biodegradable bonds. It is suggested that [Fe-PGNP]-PL-MTX may be useful in the intracellular active targeting of bonded drug(s). © 1990 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.