Adrug can be delivered to a specific site in the body in several ways, e.g. as a suspension in a liquid, intramuscular injection, subcutaneous injection or implant. Currently, rapid and effective methods of delivering and releasing a pharmacological agent at a particular site in the body in a tightly controlled manner are being sought.
Research involving controlled drug release has been ongoing for several years. Creating a matrix or carrier containing a pharmacological agent with special properties and high safety for the patient is a huge challenge. At present, the greatest interest among researchers in various scientific fields is:
- biodegradable polymeric systems
- micelles
- microparticles (of natural and artificial origin), e.g. microcapsules, microspheres
- nanoparticles, e.g. drug-polymer, nanocapsules
- liposomes.
The biggest problem so far has been to "create" a matrix that is free of its own pharmacological activity. A drug will be placed in it, the release of which will be strictly controlled. It must not accumulate in the human body and there will be no release of any toxic/adverse products during its resorption.