Monolithic protein stationary phases prepared by the sol-gel method for use in affinity chromatography

Capillary monolithic silica columns used for normal and reversed phase separations offer the advantage of lower backpressure and higher efficiency compared to packed columns. However, capillary monolithic columns have not been applied to affinity chromatography. We used the sol-gel method to encapsulate proteins in a silica matrix for capillary affinity chromatography. A monolithic protein stationary phase was prepared by the tetramethyl orthosilicate procedure. The protein containing sol was injected into a 75um i.d. capillary that had been pretreated with sodium hydroxide. The sol gelled into a rigid micro-porous and macro-porous stationary phase. The porosity of the gel was characterized by scanning electron microscopy and Brunauer-Emmett-Teller adsorption/desorption isotherms. Ubiquitin, bovine serum albumin (BSA), and catalase at different loadings were used in preliminary tests to determine the effects of protein size and concentration on the stationary phase properties. Preliminary separations were performed using the pumps from a capillary electrophoresis instrument with BSA doped monolithic columns

Ionic liquids: MALDI-MS matrices and gas chromatography stationary phases

This thesis shows the systematic variation of both the cation and anion to find an ionic liquid matrix that produces the greatest analyte S/N ratio. It is also demonstrated that these new ILMs have a greater mass detection range and can be used for a wider variety of analytes. Analytes tested include peptides, proteins, and carbohydrates. Also reported is the characterization of sixteen biodegradable polymers with two ILMs and five solid matrices. It is shown that the ILM produces less degradation and typically allows detection of an almost Gaussian distribution of analyte peaks. This allows detection of a more accurate and precise number average molecular weight and weight average molecular weight. It is also shown that the use of an ionic liquid stationary phase as the secondary column, in 2D-GC, for the separation of volatile organic compounds and 13 chemical markers found in the headspace of US currency. Tthe use of 2D-GC in the stop flow operation mode is also shown. It is also shows the separation of phosphorus-oxygen (P-O) containing compounds from a complex mixture using a triflate ionic liquid column as the secondary column in 2D-GC. These phosphorus-oxygen containing compounds are chemical warfare agent simulants. The separation of the P-O containing compounds on the triflate ionic liquid and the commercial DB-WAX (polyethylene glycol) columns are compared. It was found that the triflate IL column was much more selective for the P-O containing compounds than was the DB-WAX column