Supercritical Fluid Technology: A Promising Approach for Preparation of nano-scale Drug Delivery Systems

Various technological approaches are widely used to prepare drug nanocarriers in order to protect the active substances from the unfavourable impact of the environment (hydrolysis, enzymatic degradation, etc.) and to improve the dissolution and bioavailability. Conventional methods like grinding, spray drying, polymerization, coacervation, lyophilisation etc., are extensively used but they have some drawbacks. Ensuring a control on the particle size, particle size distribution and drug loading during the processing is the main challenge. These particle characteristics have enormous impact on the dissolution and bioavailability of the drug used. Moreover, these traditional technologies are very expensive in terms of materials, time and energy. Conversely, supercritical fluid technologies could save time and energy and provide mild conditions for the preparation of nanocarrier drug delivery systems, notably, using supercritical carbon dioxide. This mini-review aims to highlight the advantages of the supercritical fluid technologies and to emphasize the benefits of their usage compared to conventional technologies without having the claims to refer to all known methods applied already in the practice.