Abstract: The present disclosure discusses a method of separating a sample of tyrosine kinase inhibitors or metabolites of tyrosine kinase inhibitors which includes injecting the sample into the chromatographic system having one or more low-bind coated surfaces along the flow path; flowing the sample through the chromatographic system; separating the sample; and analyzing the separated sample. Consequently, the sample does not bind to the low-binding surface coatings (e.g., alkylsilyl coatings) of the flow path. The applied coating can reduce peak tailing and decrease carryover for tyrosine kinase inhibitor samples during chromatographic analysis.

Abstract: The present disclosure provides robust, high-throughput, and clinically applicable methods for simultaneously separating and quantifying the biologically active forms of Vitamin B1 (TPP) and Vitamin B6 (PLP) from human whole blood.

Abstract: Embodiments of the present invention are directed to methods and kits for determining the presence or absence, and the amount if present, of vitamin D analogs in samples. One embodiment of the present method for detecting the presence or absence of vitamin D analogs in a sample comprises the steps of adding an effective amount of a multiple charge cationic agent to the sample to form a cationic treated sample. The effective amount of a multiple charge cationic agent enhances the signal from vitamin D analogs upon analysis by mass spectroscopy.

Abstract: Embodiments of the present invention are directed to methods and kits for determining the presence or absence, and the amount if present, of vitamin D analogs in samples. One embodiment of the present method for detecting the presence or absence of vitamin D analogs in a sample comprises the steps of adding an effective amount of a multiple charge cationic agent to the sample to form a cationic treated sample. The effective amount of a multiple charge cationic agent enhances the signal from vitamin D analogs upon analysis by mass spectroscopy.

Abstract: Embodiments of the present invention are directed to methods and kits for determining the presence or absence, and the amount if present, of vitamin D analogs in samples. One embodiment of the present method for detecting the presence or absence of vitamin D analogs in a sample comprises the steps of adding an effective amount of a multiple charge cationic agent to the sample to form a cationic treated sample. The effective amount of a multiple charge cationic agent enhances the signal from vitamin D analogs upon analysis by mass spectroscopy.