| Capillary column gas chromatography and high performance liquid chromatography have revolutionized the analysis of organic molecules in biological and environmental systems. However, problems arise which limit the utility and scope of these methods for real world problems. For example, the development of sampling procedures that would enable gas chromatography to be utilized in the field could result in substantial reductions in the cost of analyses. Employing solid phase micro-extraction, a gas chromatographic method for use in the field was developed and to identify the type of fuel responsible for an underground spill. The information that is garnered from these analyses can be crucial for the design of effective remediation schemes.; Overlapping chromatographic peaks are encountered in high performance liquid chromatography. Two approaches can be taken to improve the resolution between adjacent peaks. The first approach uses mufti-wavelength detectors and mufti-variant curve resolution algorithms to resolve co-eluting species. Using principle component analysis it is possible to capture the concentration profile and spectrum of each analyte in the unresolved peak. However, the extracted chromatographic and spectral profiles are usually not in a form that is suitable for interpretation, which was the motivation for developing the varimax extended rotation. This rotation can be used to resolve chromatographic bands containing 2, 3, and 4 analytes.; The second approach takes advantage of improvements in chromatographic selectivity, which can be obtained when medium chained length alcohols (e.g. butanol and pentanol) are used as organic mobile phase modifiers. The decrease in retention time and the improvement in selectivity can be attributed to an increase in the contact surface area of the stationary phase, which is a direct result of the intercalation of the organic modifier into the bonded phase, which alters the sorbent properties of the stationary phase by changing the space available to the solute for intercalation. |
