Monolithic separation media synthesized in capillaries and their applications for molecularly imprinted networks

• Main Author: Courtois, Julien
• Format: Doctoral Thesis
• Language: English
• Published: Umeå universitet, Kemiska institutionen 2006
• Subjects: bupivacaine; etching; phosphorylated tyrosine; poly(ethylene glycol); silanization; transmission electron microscopy; fused silica capillaries; isothermal titration calorimetry; local anæsthetic; molecularly imprinted polymer; monolith; nuclear magnetic resonance; Analytical chemistry; Analytisk kemi
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-923; http://nbn-resolving.de/urn:isbn:91-7264-207-6

The thesis describes the synthesis of chromatographic media using several different approaches, their characterizations and applications in liquid chromatography. The steps to achieve a separation column for a specific analyte are presented. The main focus of the study was the design of novel molecularly imprinted polymers. Attachment of monolithic polymeric substrates to the walls of fused silica capillaries was studied in Paper I. With a broad literature survey, a set of common methods were tested by four techniques and ranked by their ability to improve anchoring of polymers. The best procedure was thus used for all further studies. Synthesis of monoliths in capillary columns was studied in Paper II. With the goal of separating proteins without denaturation, various monoliths were polymerized in situ using a set of common monomers and cross-linkers mixed with poly(ethylene glycol) as porogen. The resulting network was expected to present “protein-friendly pores”. Chemometrics were used to find and describe a set of co-porogens added to the polymerization cocktails in order to get good porosity and flow-through properties. Assessment of the macroporous structure of a monolith was described in Paper III. An alternative method to mercury intrusion porosimetry was proposed. The capillaries were embedded in a stained resin and observed under transmission electron microscope. Images were then computed to determine the pore sizes. Synthesis of molecularly imprinted polymers grafted to a core mono-lith in a capillary was described in Paper IV. The resulting material, imprinted with local anaesthetics, was tested for its chromatographic performance. Similar imprinted polymers were characterized by microcalorimetry in Paper V. Finally, imprinted monoliths were also synthesized in a glass tube and further introduced in a NMR rotor to describe the interactions between stationary phase and template in Paper VI.