**4. Conclusions**

In conclusion, microfluidic technology allows for incredibly accurate fluid delivery. It could be coupled to an actuator system that delivers drugs on demand or continuously. Microfluidics has revolutionized the design of devices for direct drug delivery in general, as well as the manufacturing of drug carriers. Microfluidic technology is required for the manufacture of drug carriers with a reproducible release profile as well as the controlled release of several substances with varied release characteristics. Materials with smart properties can be manipulated to respond in a controllable and reversible way, modifying some of their properties as a result of external stimuli such as mechanical stress or a certain temperature.
