Self-propelled Janus micromotors for pH-responsive release of small molecule drug

Oral administration of drugs has received significant attention in the last 1, 2 decades, as it is the most comfortable and painless administration route, which leads to high patient compliance. Although oral delivery of drugs shows positive effects in patients, several hurdles must be overcome such as enzymatic degradation, large pH-variations found throughout the gastrointestinal (GI) tract, and continuous mucus secretion. We have studied biocompatible non-toxic micromotors as promising man-made microdevices for targeted furosemide release. Micromotors are micro-scale autonomous entities that can perform various tasks in the GI tract as a result of their impressive motion abilities. Their directional motion makes them ideal candidates to bring the necessary drug dosage to where it is needed. Herein, the micromotors were loaded for the first time with furosemide and coated with pH-sensitive polymer Eudragit® L100 using ultrasonic spray coating technique in order to achieve targeted drug delivery and pH-responsive release. Coherent anti-Stokes Raman scattering spectroscopy (CARS) was used for visualizing drug loading efficiency on the surface of micromotors. In vitro drug release was evaluated under acidic and neutral pH chemical environments and obtained results confirm their function as pH-sensitive microdevices for a drug release.