Synthesis And Analysis Of ATP-Independent Enzyme-Powered Micropumps

Open Access
Author:
Agrawal, Arjun
Area of Honors:
Chemistry
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Ayusman Sen, Thesis Supervisor
  • Raymond L Funk, Honors Advisor
Keywords:
  • Enzymes
  • Nanomotor
  • Chemistry
  • Urease
  • Catalase
  • Lipase
  • Glucose
  • Insulin
  • Hydrogel
  • Imprinted
  • Intelligent
Abstract:
The next generation of smart devices will need to incorporate the ability to self-regulate, in the absence of a constantly supplied source of energy, and be bio-friendly. The system demonstrated here displays these characteristics using enzymatic reactions as a power source for micropumps that can be used for sensing and detection. Surface-immobilized enzymes can function as both sensors and micropumps that create the pumping of fluid in a directional manner in response to increasing substrate concentration. These systems are independent of cellular energy in the form of adenosine triphosphate, and depend only on the enzyme’s substrate to create fluid flow. They are minutely self-regulating depending on the amount of substrate concentration available in surrounding fluid. The robustness of this system was demonstrated via spatial and temporal analysis, and the pumping mechanism was determined to be density-dependent. These surface-immobilized enzyme systems were then adapted for use in more biocompatible hydrogel scaffold systems. These gels could be loaded with small molecules such as dyes or drugs and pump these molecules out in the presence of substrate. It was demonstrated here that enzymes electrostatically attached to the surface of gels could be used to generate fluid flows through their pumping mechanism and help to actively release various concentrations of drug in response to substrate concentration. This led to the eventual design of two important systems, one which pumped out insulin in the presence of glucose, and another which rapidly pumped out 2-PAM, a potent antidote to treat nerve agent poisoning. The creation of these systems will be intrinsic to the next generation of smart devices as sensors and pumps, potentially for use within the human body.