Colloidal Design at the Nano, Micro, and Macro Scales: Materials that Can Move, Morph, Protect and Heal

Abstract

Our laboratory seeks to engineer colloidal building blocks (polymers, surfactants, and particles) into a variety of functional fluids and soft materials. Our work extends across the length scales. Many of our systems are ‘smart’, i.e., their properties can be tuned by an external stimulus. 

At the nanoscale, we study molecular self-assembly into micelles, vesicles, and tubules. In addition, we have created self-assembling biopolymers that convert liquid blood into a gel; thereby, these ‘hemostatic’ materials stop bleeding from injuries. This research has resulted in a commercial product (Rapid-Seal Wound Gel) that is available across the USA.

At the microscale, we create polymer capsules inspired by the architecture of biological cells or tissues. Examples include: capsules with many inner compartments; onion-like capsules with multiple layers; capsules that move in water in the presence of a chemical fuel; and capsules that act as ‘miniature factories’, synthesizing products on-demand.

At the macroscale, we make hydrogels with unusual properties. Examples include: gels that can protect a delicate object from impact, and ‘gel-sheets’ that  absorb water and blood better than cloth, paper, or gauze. We have also found a way to adhere gels to tissues by applying a low electric field, which may enable surgeries to be performed without sutures.  

Biography

Professor and Fischell Fellow Srinivasa Raghavan received his BTech and PhD in chemical engineering from the Indian Institute of Technology, Madras, and North Carolina State University, respectively. His research has resulted in more than 200 publications and 20 patents, which have been cited more than 21,000 times (h index of 80). At UMD, he has been named a Distinguished Scholar-Teacher, recognizing excellence in both research and teaching. He won a UMD Invention of the Year in 2009 and 2022 and has been elected a Fellow of the National Academy of Inventors (NAI). He is also the scientific co founder of five startup companies based on technologies invented in his laboratory.