Abstract
Magnetic microspheres are supramolecular particles that are small enough to circulate through capillaries without producing embolic occlusion (<4 μm) but are sufficiently susceptible (ferromagnetic) to be captured in micro vessels and dragged into the adjacent tissues by magnetic fields of 0.5-0.8 Tesla (T). Methods of preparation of magnetic microspheres are namely phase separation emulsion polymerization (PSEP) and continuous solvent evaporation (CSE). Ideally less than 125 p that can be suspended in aqueous vehicle and injected by an 18 or 16 number needle. The amount and rate of drug delivery via magnetic responsive microspheres can be regulated by varying (i) Size of microspheres; (ii) Drug content; (iii) Magnetite content; (iv) Hydration state; (v) Drug release characteristic of carrier. different approaches for magnetic targeting:- Chemical approach prodrug are Compartment delivery, Natural targeting, Ligand mediated targeting, Physical. There are various types of methods are used to prepare magnetic microshere along with different evaluation paremeters.
