Microfabrication-derived DDS: From batch to individual production

As a result of recent advances in microfabrication technology (MFT), microparticles including microcapsules and microspheres can be prepared individually and the disadvantages of the conventional microparticles produced by batch production, i.e. (i) low loading efficiency, (ii) large size variation, and (iii) initial burst release, have been remedied. In addition, all conventional microparticles have the same structure, a spherical shape, so they have only one function, sustained release. Threelayer microcapsules (TLMCs) have been designed to address these issues. TLMCs consist of a surface layer, a drug carrying layer, and a basement layer. TLMCs have sustained release as well as adhesiveness and targeting functions. TLMCs are prepared using ink-jet printer nozzle technology. The obtained TLMCs are used for the oral delivery of peptide/protein drugs and long-term sustained-release injection preparation. In addition, self-dissolving micropiles (SDMPs) can be individually produced by MFT as a percutaneous preparation. MFT allows biopharmaceutical drugs like insulin, erythropoietin, and growth hormone to be absorbed through the skin. Thus, advances in MFT have accelerated the development of pharmaceutical technology.