New Drug Delivery System Based on Mussel Adhesive Proteins

TAGS:  Sustainability / Natural Adhesives    

POSTECH research team led by Professor Hyung Joon Cha (Ph.D. candidate Hyun Sun Choi) in the Department of Chemical Engineering in collaboration with Professor Yun Kee Jo of the Department of Biomedical Convergence Science and Technology at Kyungpook National University have together developed magnetically guidable mussel protein-based adhesive microbots.

Magnetic guidance refers to the property of moving in the direction of a magnetic field in response to an external magnetic field.

Microparticles Provide Locoregional Delivery of Drugs

The microbots based on mussel adhesive protein (MAP) helps apply therapeutic drugs to a specific lesion site when esophageal disorders occur. Without microbots the drugs fail to remain in the target site for a long period of time due to hydrodynamic shear force¹ and drag force².

The microparticles developed by Professor Cha's team can control their movement in the direction in which a magnetic field is applied, and can provide locoregional delivery of therapeutic drugs to the targeted lesion site in dynamic fluid-associated conduit organs for a prolonged period.

Conventional magnetically guided drug delivery systems have a limitation in that drugs easily disappear in highly dynamic fluids environment of the body when the magnetic field is removed after the drugs are delivered to the target sites.

MAP Keeps Microparticles at Site After Magnetic Field Removal

To this, the research team loaded iron oxide nanoparticles in the microparticles. They are then delivered locally to the lesion site primarily by the magnetic field in the passageway through which fast fluid flows. Thanks to the superior underwater adhesive properties of the mussel adhesive proteins, the microparticles remain at the site for a prolonged period even after the magnetic field is removed.

From experiments, the researchers confirmed that the delivery efficiency was 5.17 times higher in the presence of a magnetic field than the magnetic field-free conditions. In addition to the excellent biocompatibility of the microparticles, Professor Cha's team experimentally verified their high anticancer effects by loading doxorubicin – a chemotherapy drug widely used for cancer treatment – in the microparticles to increase the cytotoxicity of cancer cells to about 84%.

The therapeutic effects were maintained at the delivery site for long periods of time even after the magnetic field was removed. This is significant in that it demonstrates excellent therapeutic effects for patients with esophageal disorders even with a small dose of drugs and low frequency of administration. Due to the nature of these microparticles,their location can even be tracked in real time via magnetic resonance imaging³.

“The microbot therapeutics delivery system developed in this study is widely applicable in treating disorders that occur in organs that involve rapid fluid flow, such as the esophagus as well as the intestine,” explained Professor Cha on the significance of the research.

1. Shear force
A force acting in parallel along a plane within an object when equal magnitude and opposite forces act simultaneously on an object. In particular, in fluid mechanics, it is also referred to as a deflection or shear stress.

2. Drag force
The resistant force exerted by a fluid when an object is moving or at rest in a flowing fluid, also called fluid resistance.

3. Magnetic resonance imaging (MRI)
A technique in which a device composed of magnets emits high-frequency waves to the human body to resonate hydrogen nuclei in body parts, and the difference in signals from each tissue is converted into digital information then visualized.

Source: POSTECH

Source: POSTECH