Magnetic liposomes

In Drug Delivery

Magnetic Particles

Magnetic liposomes can provide a minimally invasive method to treat tumors and other diseases that would be difficult for surgeons to access and treat. This method can also be used to guide drugs to a specific location within the body when the vesicles are in the presence of a magnetic field, thus becoming magnetized.

Along with the drugs of interest, ferrofluids (Figure 3) are also encapsulated into the liposome and are the items which magnetize the liposome. Ferrofluids are liquids consisting of an aqueous dispersion of magnetic iron oxides or other magnetic particles in the nanometer size range, causing the ferrofluid to become polarized in the presence of a magnetic field. The nanometer size of the particles is favorable since they would be small enough to flow through blood capillaries to reach most areas within the body.

A potential problem associated with these magnetic particles is clumping.  But this issue is somewhat resolved by coating the particles with soap or detergent suspended in an organic solvent or water.  This prevents agglomeration due to magnetic attraction between the particles and van der Waals forces.

These particles impart its magnetism to the liposome, and will only exhibit magnetic properties when exposed to an external magnetic field.  This is advantageous in inhibiting clumping or agglomeration in undesirable areas.

Once the liposome reaches the desired area, it must be broken to release the drugs of interest. Liposomes are broken when when heated by being exposed to an alternating magnetic field which vibrates the magnetic particles. The liposome is broken by the particles, thus the encapsulated drug is massively released.

 

 

E-mail: bshergil@uci.edu

Figure 3: Ferrofluid under influence of a magnetic field

Bhupinder Shergill

BME 240 UC Irvine