Stabilized and Functionalized Self Assembled Nanoparticle Arrays for Protein Separation

• Author / Creator

  Shaabani, Narges

• This thesis reports a facile method to stabilize colloidal self-assembled (CSA) 310 and 50 nm nanoparticles packed in microchannels for high speed size-based separation of denatured proteins. Silica nanoparticles, self-assembled in a network of microfluidic channels, were stabilized with a methacrylate polymer prepared in situ through photopolymerization. The entrapment conditions were investigated to minimize the effect of the polymer matrix on the structure of packing and the separation properties of the CSA beds. Scanning electron microscopy (SEM) shows the methacrylate matrix links the nanoparticles at specific sphere-sphere contact points that improves the stability of the CSA structure at high electric fields (up to at least 1,800 V/cm) and allows fast and efficient separation. The optimized entrapped CSA beds demonstrated better separation performance than similarly prepared on-chip CSA beds without the polymer entrapment. Polymer entrapped CSA beds also exhibited superior protein resolving power. The minimum resolvable molecular weight difference of proteins in the polymer entrapped CSA bed is 1-2 kDa comparing ~9 kDa for the native silica CSA bed without polymer entrapment. The method and the processes required to photograft charged monomer to 310 nm silica nanoparticle surface for native protein separation is described. Photo-initiated polymerization enabled coating the nanoparticles in microfluidic devices. The surface chemistry was then tailored to fit the specific application by subsequent photografting of the surface. This coating strategy allows a fast and robust wall coating with controlled surface chemistry and surface biocompatibility. The results indicate that the coatings are quite effective in reducing protein adsorption, compared to a native silica particle packed bed.

• Subjects / Keywords

  • Self Assembled Nanoparticle Arrays, Protein Separation, Stabilized and Functionalized Self Assembled Nanoparticle

• Graduation date

  Fall 2016

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R33F4M23K

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.