The role of modifiers in supercritical fluid extraction (SFE) technology is to augment the solubilizing characteristics of supercritical carbon dioxide for achieving efficient extractions of target analytes. This work will serve to investigate the effects of various modifiers from a mechanistic point of view to determine extraction kinetics and modifier efficiencies. This will be done while incorporating sample matrix effects as well as secondary modifiers. Target analyte collections will be accomplished by the trapping of the extraction efffluent in a cryogenic trap packed with an adsorbent. Moreover, the effect of modifiers on different adsorbents will also be explored. Statistical data obtained from these various experiments will be used to obtain protocols for off-line SFE when using modifiers and cryogenic absorbent trapping for use in various applications. This base of knowledge will then be applied in Phase II to the development of analytical methodologies effecting agricultural/agrichemical research such as the development of methods to extract pesticides and herbicides from soils, feeds, fruits and vegetables.
Anticipated Results:Commercial applications resulting from this work will include analytical methods that can be used by agricultural and other research laboratories. This is of significance due to the need to replace the widespread laboratory use of toxic liquid solvents (i.e. freons, methylene chloride) that are used extensively in analytical methodologies. In addition, dedicated sample preparation instrumentation incorporating these new analytical methods will be developed to allow the widespread use of the new sample preparation technology.
