ENHANCED PARTICLE DIFFUSION THROUGH ENZYME CATALYSIS AND SILVER TITANIA NANOMOTORS

Open Access
Author:
Surve, Shraddha Vishwas
Graduate Program:
Chemistry
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
October 18, 2010
Committee Members:
  • Ayusman Sen, Thesis Advisor
Keywords:
  • enzymes
  • catalysis
  • nanomotors
Abstract:
In the first part of this thesis, I explore the use of enzymes as catalytic motors in order to drive nanoparticles. The two enzymes on which this thesis focuses are horseradish peroxidase and glucose oxidase. Chapter 2 describes the synthesis of carboxylated polystyrene-silica Janus particles. Horseradish peroxidase is immobilized on the carboxylated polystyrene half of the Janus particle, both with and without a linker between the enzyme and the Janus particle. Diffusion coefficients of these particles are measured to check for enhanced diffusion. In Chapter 3, an enzyme cascade system of horseradish peroxidase and glucose oxidase has been investigated for predator-prey like behavior. Both the enzymes are immobilized on different polystyrene nanospheres and motion of the spheres is observed in substrate solution of glucose and oxygen. Optical microscopy experiments and diffusion coefficient measurements are carried out in order to study the predator-prey behavior of these nanoparticles. Chapter 4 describes the second part of the thesis, which involves design and synthesis of Ag-TiO2 particles. Autonomous motion of Ag-TiO2 particles can be observed in the presence of hydrogen peroxide solution. Particle motion and inter-particle interactions can be altered by subjecting the system to UV light trigger.