Modified cyclodextrin coated magnetite nanoparticles for targeted delivery of hydrophobic drugs

Abstract

The invention discloses a composition comprising surface modified iron oxide nanoparticles with citric acid modified cyclodextrin with a hydrodynamic diameter of less than 10 nm and a hydrophobic molecule. The composition finds use in targeted delivery of a hydrophobic drug and as contrast agent in imaging applications.

1 - 4 . (canceled) 
     
     
         5 . A process for preparation of a hydrophobic drug loaded beta-cyclodextrin-citrate coated magnetic nanoparticles comprising the following steps:
 a. dissolving a hydrophobic drug in a suitable solvent and then adding beta-cyclodextrin-citrate coated magnetite nanoparticles and stirring gently for 6-8 hrs to obtain a mixture; and   b. stirring the mixture obtained in step (a) for 8-12 hrs, then centrifuging the mixture at 4000-5000 rpm for 5-8 minutes, and then drying to obtain the hydrophobic drug loaded beta-cyclodextrin-citrate coated magnetite nanoparticles.   
     
     
         6 . The process of  claim 5 , wherein the suitable solvent in step (a) is selected from the group consisting of acetone, cyclohexane, and DMSO. 
     
     
         7 . The process of  claim 5 , wherein the hydrophobic drug in step (a) is selected from the group consisting of curcumin, doxorubicin, taxol, methotrexate, and vincristine. 
     
     
         8 - 9 . (canceled) 
     
     
         10 . The process of  claim 5 , wherein prior to step(a) the beta-cyclodextrin-citrate coated magnetic nanoparticles are prepared as follows:
 i. dissolving β-cyclodextrin and citric acid in a ratio between 3:1 and 5:2 in water, to obtain a mixture and then stirring the mixture at a temperature of 70-80° C. for 3-4 hrs to obtain a transparent solution;   ii. treating the transparent solution obtained in step (i) with an alcohol, and then washing and drying at a temperature of 60-70° C. for 24-26 hrs to obtain a cyclodextrin-citrate complex;   iii. dissolving the cyclodextrin-citrate complex obtained in step (ii) in water to obtain a cyclodextrin-citrate solution;   iv. separately mixing ferric chloride hexahydrate and ferrous chloride tetrahydrate in a molar ratio from 2:1 to 5:3 in water and ammonium hydroxide solution and then stirring and washing to obtain magnetic nanoparticle;   v. redispersing the magnetic nanoparticles obtained in step (iv) and then adding the cyclodextrin-citrate solution obtained in step (iii) with stirring for 4-5 hours at temperature of 80-90° C. to obtain a stable dispersion of beta-cyclodextrin coated magnetite nanoparticles;   vi. dialyzing the beta-cyclodextrin coated magnetite nanoparticles dispersion obtained in step (v) against water for 3-4 days at a temperature of 60-70° C. to obtain coated solid nanoparticles; and   
       dispersing the coated nanoparticles obtained in step (vi) in water at the physiological pH to obtain the beta-cyclodextrin-citrate coated magnetite nanoparticles. 
     
     
         11 . The process of  claim 10 , wherein the alcohol used in step (ii) is 2-propanol.