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Colloidal Drug Delivery
Colloids may be defined as dispersed or encapsulated systems which typically have very small particle sizes (nanometers-to micrometers). These nano-scale dispersed systems have considerable application in drug delivery and formulation science.
For example there is a wide range of drugs that need to be encapsulated to be delivered efficiently. Hydrophilic drugs such as proteins need to be protected from chemical and enzymatic degradation when delivered orally and encapsulation in an appropriate matrix can help facilitate their protection and effective delivery. Meso-phases are an intermediate state of matter with the fluidity of a liquid and some of the molecular order of a solid. These systems further offer the ability to encapsulate both hydrophilic and lipophilic drugs and the means to release their drug load in a controlled manner. Encapsulation technology is also utilised in the application of herbicides and pesticides.
Colloids also play a significant role in the absorption of poorly water soluble, lipophilic drugs. This class of drug is typically poorly absorbed after oral administration, however their absorption may be enhanced by formulation in combination with lipids and in particular lipidic-colloidal systems such as emulsions and microemulsions. These systems maintain drug molecules in a lipidic dispersion in the gastrointestinal tract, thereby avoiding drug precipitation and promoting absorption. This technology has been successfully applied to current drug products such as Sandimmun Neoral® (cyclosporin) and Fortovase® (saquinavir).
Specific projects include:
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