Bead based microreactors for sensing applications
Abstract
The dissertation research described here focuses on the fabrication and
modification of the polymeric beaded sensing elements, one of the many critical
components of a Microbead Array Chip-Based Multianalyte Detection System.
Detection of biomolecules including proteins and oligonucleotides are based on
affinity interactions between carefully selected ligands immobilized on the sensing
microspheres. The current work relies on microspheres made of agarose gel shaped
into micron sized beads with intrinsic porosity associated to the concentration of
agarose in the gel. The beaded material described is considered of a homogeneous
nature with limited transport capabilities although superior to homogeneous latex
beads. The microbead array system potentially benefits from structural
modifications on the sensing elements and includes improvement on the mobile
phase mass transport, capture of larger particles, faster assays, and the increase in
the multiplexing capabilities. Efforts are also directed to preferentially modify gels
made of agarose to facilitate the transition from the existing sensing elements to the
new beaded designs made of the same polysaccharide. As a result the chemistry
utilized to attach affinity ligands to procure reactive sensing elements remained
practically the same. Collectively, these research activities have resulted in a
number of novel polymer-based reactive particles that have the potential to service
a variety of new sensing applications.