Several Finnish universities have joined forces to develop an innovative drug delivery method that utilises silicon to transport drugs in the human body. Among other advances, the project has been able to sustain the effect of peptides controlling appetite, which may facilitate the use of nanotechnology for dieting purposes. The research is being carried out as part of the Academy of Finland's Research Programme on Nanoscience (FinNano).
Different types of drug molecules can be bound to the porous structure of silicon, thereby making it possible to alter their properties and control their behaviour within the body.
Porous silicon can be produced as both micro- and nanoparticles, which facilitates the introduction of the material through different dosing routes - orally, as injections or subcutaneous applications. Furthermore, biodegradable nanoparticles can be used for drug targeting.
Silicon is more familiar as a raw material used in computer microprocessors. In nanomedicine applications, the wafers are equipped with nano-sized pores instead of processors. The pores are slightly larger than the drug molecules loaded in them. The porous surfaces of the silicon particles, created through a process called electrochemical etching, are modified to be chemically suitable regarding the molecules to be loaded in the pores and the application. The drug is loaded by immersing the particles in a suitable drug solution, whereby sensitive substances, such as peptides and proteins, can also be easily loaded into the pores effectively.
The biopharmaceutical properties of the drug in the pores are different from those of the original drug. The rate of release for pore-bound drugs can be changed in a controlled manner by selecting the proper pore size and surface chemical properties in relation to the size and chemical properties of the drug molecule.