Many methods in use today for the isolation, purification, and
identification of the staphylococcal enterotoxins involve lengthy
steps with significant loss of enterotoxin, are subject to interference
from contaminating sample components, and lack sufficient specificity.
Culture extracts of enterotoxin producing Staphylococcus
aureus strains (enterotoxins A-E), crude enterotoxin preparations
The distribution of hydrophobic ionogenic organic compounds
(HIOC's) between aqueous and nonaqueous phases has been
investigated. The HIOC's are aniline and methyl substituted
anilines. The aqueous phases are methanol-water mixed solvents with
varying pH and ionic strength. The nonaqueous phases are silica and
alkyl derivatized silica with ethyl- (C-2), octyl-...
The challenges prompted by miniaturization of chromatographic systems have led
scientists to explore new avenues in the synthesis of stationary phases. Packed capillary
columns have found limited application in routine analysis due to a number of technical
difficulties, most of which are attributable to the frits. New column designs insure...
For a number of reasons, miniaturization of chromatographic columns has been
a general trend over the past three decades. Methods designed to enhance selectivity
and efficiency can offer improved separation power and speed, expanding on the
advantages of miniaturized columns. This dissertation describes novel approaches in
this direction, focusing on...
Over the last decade, the miniaturization of analytical systems has become
an increasingly important and interesting research area. Miniaturized systems offer
many advantages, including reduced reagent and sample consumption, shorter
analysis times, portability and disposability. This dissertation describes novel
approaches in this direction, focusing on two areas: the miniaturization of...
Metabolomics is a comprehensive analysis of small molecules, or metabolites, in a system. Metabolomics is a hypothesis-generating experiment and offers an unbiased analysis of cell metabolism that can aid in the understanding of fundamental biological processes. Metabolomics is widely and broadly applicable in the biological sciences and has been used...
A new general method is developed for the optimization of
HPLC ternary or pseudo-quaternary mobile phases which are
represented by the trilinear coordinate system. This method can
predict the global optimum of the mobile phase composition. The
global optimum composition along each edge of the triangle and
the corresponding selectivity...
A sensitive, selective, rapid analytical method based on large-volume injection (LVI)
liquid chromatography/ tandem mass spectrometry was developed using
commercially-available hardware that eliminates the need for either off-line or on-line
solid phase extraction. Centrifugation followed by the direct injection of 1,800 µL
was used for the quantification of illicit drugs,...