Detection and analysis of soft nanoparticles by the resistive pulse method

Soft nanoparticles have become increasingly important to the scientific and medical communities particularly in drug delivery systems due to their ability to deliver drugs in a time-dependent or site-specific manner. However, much is left unexplored in their permeation and translocation through porous biological membranes, such as those found in the body. This dissertation presents investigations of the resistive-pulse detection and analysis of soft nanoparticles including microgels and liposomes, using conical nanopores embedded in glass membranes. This analysis provides a first look at the permeation and translocation of soft nanoparticles through a porous membrane. Chapter 1 overviews nanoparticles and their uses in the scientific and medical communities, as well as the resistive-pulse technique and the glass nanopore membrane. Chapter 2 describes investigations on the pressure dependent deformation and translocation of 570 nm radius pNIPAm-AAc microgels through small conical nanopores in glass membranes using the resistive-pulse technique. Translocation event rates, durations, and current pulse heights are found to be a function of the relative conductivities of the microgel and the electrolyte solution. Also, a statistical analysis technique is used to determine the probability of coincident events.