SAMIR MITRAGOTRI
University of California, Santa Barbara

BIO-INSPIRED STRATEGIES FOR TARGETED DRUG DELIVERY

Abstract

Polymeric nanoparticle drug delivery systems are widely explored to improve the biological outcome of encapsulated drugs for therapeutic effects. Unfortunately, nearly all synthetic materials, polymeric particles included, suffer from limited abilities in vivo.  Poor vascular circulation, limited targeting and the inability to negotiate many biological barriers have prevented the overwhelming majority of polymeric particle drug delivery systems from entering the clinic. To further complicate this, the above requisites must be performed simultaneously while also limiting toxic side effects. Mother Nature has provided us with several examples of successful carriers in the form of circulatory cells and they provide inspiration for advanced drug carriers. We have developed blood-cell-inspired drug delivery systems that benefit from the natural delivery abilities of the main individual cellular components of blood: (i) erythrocytes, (ii) leukocytes and (iii) thrombocytes.

Two main strategies have been developed in our laboratory to take advantage of blood-cell delivery mechanisms: the first, known as cellular hitchhiking, involves non-covalent attachment of nanoparticles to the surface of mammalian cells and the second, design of synthetic cells, involves incorporating key biophysical and biochemical design parameters of natural platelets into platelet-like nanoparticles. The cellular hitchhiking of: (i) adsorbed nanoparticles to the surface of red blood cells for prolonged circulation and lung targeting in vivo, and (ii) antibody attached flat disc shape “cellular backpacks” to the surface of monocytes for specific targeting to inflamed tissues in vivo will be discussed. Synthetic platelets which mimic the shape, flexibility and complex biochemical interactions of natural platelets have also been developed in our laboratory to induce hemostasis, like their real life counterparts, and prevent blood loss following vascular damage in vivo. The use of circulatory blood cells offers a new design paradigm for nanomedicine.

SAMIR MITRAGOTRI is a Professor of Chemical Engineering at the University of California, Santa Barbara (UCSB). He also serves as the Founding Director of UCSB’s Center for Bioengineering and the Director of Translational Medical Research Laboratories. He received Ph.D. from MIT and B.S. from Institute of Chemical Technology, Mumbai. Prof. Mitragotri’s research is focused in fields of transdermal drug delivery, oral drug delivery and nanoparticle-based drug delivery systems. Professor Mitragotri has published over 175 publications in leading scientific journals. He is an inventor on over 80 pending or issued patents. Prof. Mitragotri has co-founded seven companies focused on various drug delivery and detection technologies. Professor Mitragotri is an elected fellow of National Academy of inventors (NAI), American Institute of Medical and Biological Engineering (AIMBE), and American Association of Advancement in Science (AAPS). He is also the recipient of American Institute of Chemical Engineering’s Allan P. Colburn, Controlled Release Society’s Young Investigator award and Technology Review Young Inventor award (TR35). He serves as the Associate Editor of Journal of Controlled Release.

For more info: www.chem-eng.utoronto.ca/news.htm

Websites of Interest

• University of Toronto
• Faculty of Applied Science & Engineering
• Department of Chemical Engineering & Applied Chemistry