The emerging need of nanorobots and microrobots in therapeutic applications
By Vivek Agrahari, CONRAD / Eastern Virginia Medical School (EVMS), Arlington, VA, USA and Puneet Tyagi, Dosage Form Design and Development, Biopharmaceutical Development R&D, AstraZeneca, Gaithersburg, MD, USA.
The authors are part of the AAPS Nanotechnology Community Leadership Team.
The recent progresses made in the fields of nanotechnology and microfabrication methods have created programmable nanorobots and microrobots (NMRts) as innovative drug delivery products. The NMRts represent a promising option to improve the therapeutic efficacy of drugs (small or large molecules) and cells for targeted and personalized biomedical applications.1-3 NMRts are a new generation of programmable systems comprising multiple components, which can actively navigate in complex biological environments controlled by various externally-controlled (magnetic, light, acoustic, ultrasound, heat, etc.), self-controlled (chemicals or enzymes from their surroundings), or bio-hybrid (bacteria-, virus-, sperm-, and cell-based) propulsion mechanisms.4,5 These systems can also be designed to provide stimuli-responsive drug release at the target site. Encouraging results using these novel modalities have been achieved in cancer, and other indications (gastrointestinal, neurological, cardiovascular, ocular), along with oral vaccine delivery.
Another promising application of NMRts is in cell transplantation and transforming the body’s own cells, such as red blood cells (RBCs), leukocytes, and platelets, for biocompatible drug delivery. Due to their higher biocompatibility, negligible immunogenicity, long blood circulation, and intrinsic binding specificity, these cells have a natural edge compared to synthetic nanocarriers, and ultimately increase therapeutic efficacy while reducing unwanted side effects. Based on these promising developments, we present an overview of emerging therapeutic applications of NMRts in drug or cell-based therapy. The development and translational challenges for a successful clinical applicability have also been briefly discussed.