Core-Shell nanoparticles as drug delivery vehicles

Targeted drug delivery, magnetic resonance imaging (MRI), diagnosis and treatment of diseases are just a few examples of the wide range of applications of polymer metal nano-particle (NP) hybrids. The field has received further impetus when it comes to controlled release of drug in response to external stimulus. The current project has investigated the synthesis and characterization of Fe@Ag NPs followed by their functionalization, with an aim to study the loading efficiency and release kinetics of a standard drug, paracetamol. Spherical Fe@Ag NPs with an average diameter of 39nm have been synthesized using a solution based synthetic route, employing heterogeneous nucleation on pre-synthesized Fe core NPs. These NPs were functionalized using functional polymers (PNIPAM and Poly Lysine) and a carrier protein, BSA (Bovine serum albumin) and thereafter used to study paracetamol loading. The loading efficiency was optimized with respect to particle concentration and drug concentration, achieving upto 8% of loading eeficiency. In order to further enhance the loading efficiency, modified BSA nanoclusters were used. A loading efficiency of upto 6% was achieved and to ascertain high loading efficiencies, a complete matrix of parameters needs to be comprehensively studied. Release kinetics of the paracetamol was observed to be very slow. The reason for this observation is attributed to hydrophobic interactions between the drug and the polymer/protein which accounts for a high loading efficiency and a non-efficient release kinetics. Within the scope of the work, it is hereby claimed that the interactions between the drug and the nano-carrier plays a major role in determining both loading efficiencies and release kinetics. Further understanding of these systems require a complete matrix study of the various parameters responsible for altering these interactions pH, temperature, nature of drug, surface functionalization of nano- carriers and so on