Fabrication of biodegradable polymeric micro chambers encapsulated with pulverized drug for bacteria-based microrobots

This paper presents a method of fabricating pulverized drug, Lapatinib (Tykerb®), loaded micro chambers made of a biodegradable polymer, poly (ε-caprolactone) (PCL), for bacteria-based microrobots. The PCL is a biodegradable, biocompatible polymer which is approved by the U.S. Food and Drug Administration (FDA) for use in the implantable medical devices. Lapatinib is approved by the U.S. FDA for the treatment of advanced or metastatic breast cancer. In order to realize bacteria-based microrobots, selective bacterial adhesion is necessary which can enhance directional locomotion of the bacteria-based microrobots. The x-ray lithography process can be used for biodegradable polymer micromachining to fabricate structures with various shapes which can be applied for bacteria-based microrobots. A pulverized drug is used because a liquefied drug cannot be used for the x-ray lithography process. To fabricate pulverized Lapatinib loaded micro chambers, the PCL films are prepared by the solvent casting method and lamination process. Lapatinib is encapsulated between the PCL films by the screen printing method. The x-ray lithography process is then used for fabrication of micro chambers. The fabrication results indicate that the proposed method is appropriate for fabrication of biodegradable polymeric micro chambers encapsulated with the pulverized drug for bacteria-based microrobots.