Abstract: MALDI-MS operated slightly under matrix storm conditions with a high-energy-transfer, acidic matrix, or these conditions with a high sample to matrix ratio, can with ultrasensitivity detect a nucleobase, modified or canonical, of a nucleic acid species as a jettisoned, protonated molecule.

Abstract: Disclosed is a method of desorbing an adsorbed material by subjecting to energy a diazirine adsorbed on a solid surface or a layer on the solid surface, which causes the diazirine to form a carbene and nitrogen gas; and using the energy of the resultant nitrogen gas to desorb the adsorbed material from the solid surface or a layer on the same. Also disclosed is a method of reacting the resultant carbene with (a) a material in the gas phase proximal to the first solid surface; (b) a material adsorbed on a second solid surface proximal to the first solid surface; or (c) a second solid surface proximal to the first solid surface.

Abstract: The present disclosure relates to a method for detecting a compound, comprising the steps of: contacting a compound with a solid analytical surface (SAS), thereby forming an SAS with an absorbed compound; contacting the SAS with the absorbed compound with a mass tag, wherein the mass tag reacts with the absorbed compound, thereby forming an SAS with a covalently mass-tagged absorbed compound; and detecting the covalently mass-tagged absorbed compound by mass spectrometry. Also disclosed is a device for collecting breath aerosol, comprising a card or an envelope, wherein the card or the envelope comprise a tab, wherein the tab is a SAS.

Abstract: The disclosure relates to a diazirine precursor mass tag compound represented by structural formula (I) Also disclosed is a method for detecting analytes in a sample, comprising derivatizing the analytes with the compound of formula (I), and detecting the resulting derivatized analytes by a mass or ion mobility spectrometry.

Abstract: Disclosed is a method for detecting the presence of a DNA adduct in DNA. The method involves the pre-labeling of an adducted nucleotide in the DNA with a quaternary ammonium compound.

Abstract: MALDI-MS operated slightly under matrix storm conditions with a high-energy-transfer, acidic matrix, or these conditions with a high sample to matrix ratio, can with ultrasensitivity detect a nucleobase, modified or canonical, of a nucleic acid species as a jettisoned, protonated molecule.

Abstract: The present disclosure relates to a method for detecting a compound, comprising the steps of: contacting a compound with a solid analytical surface (SAS), thereby forming an SAS with an absorbed compound; contacting the SAS with the absorbed compound with a mass tag, wherein the mass tag reacts with the absorbed compound, thereby forming an SAS with a covalently mass-tagged absorbed compound; and detecting the covalently mass-tagged absorbed compound by mass spectrometry. Also disclosed is a device for collecting breath aerosol, comprising a card or an envelope, wherein the card or the envelope comprise a tab, wherein the tab is a SAS.

Abstract: Systems and methods employing beds of bagged and caged absorbent and adsorbent materials are disclosed. These inventions are useful in the area of solid phase extraction.

Abstract: Disclosed are devices comprising a porous sorptive tab and a substructure, such as a face mask, for collecting breath aerosol from a subject. The device is configured such that, in use, a subject breathes onto or through the sorptive tab. Also disclosed are specific methods of analyzing breath aerosol from a subject.

Abstract: Disclosed herein are gel and plastic compositions comprising tightened layers of polymerized vinyl monomers, as well as methods of making the same, where the layers are tightened in having smaller pores. The tightened layers comprise tightened inner layers and exterior layers, and the compositions comprise polymer-attached (pendant) initiator or helper residues.

Abstract: Systems and methods employing beds of bagged and caged absorbent and adsorbent materials are disclosed. These inventions are useful in the area of solid phase extraction.

Abstract: Disclosed herein are gel and plastic compositions comprising tightened layers of polymerized vinyl monomers, as well as methods of making the same, where the layers are tightened in having smaller pores. The tightened layers comprise tightened inner layers and exterior layers, and the compositions comprise polymer-attached (pendant) initiator or helper residues.

Abstract: Analytical chemical reagents termed non-signal imidazoles and a method for their use that provide a host of advantages for analysis of phosphomonoesters are described. The method and compounds of the invention provide a host of advantages for the analysis of phosphomonoester-containing compounds, namely characteristic, multi-analyte detection with high sensitivity and specificity of known and unknown phosphomonoester-compounds simultaneously.

Abstract: Ultrasensitive detection of a chemical substance (analyte) by mass spectrometry is achieved by employing a molecular tag that yields an intense parent ion and then an intense daughter ion in a multi-stage mass spectrometer.

Abstract: Analytical methodology is disclosed in which a trace analyte in a sample is tagged to increase its signal strength for measurement, and an affinity substance is used at least after the tagging step (late in the method) to separate the tagged analyte from tagging noise, wherein the affinity substance is directed at the reactive part of the tag, at the reagent-reacted part of the tag, or at a nonreactive part of the analyte. This method includes the case where exposure of the sample to the affinity substance begins prior to and continues after the tagging reaction. The affinity substance comprises an affinity reagent such as an immobilized anti-body (immuno-affinity chromatography). This late use of an affinity substance (after the tagging reaction) is particularly important for methods in which trace analytes are reacted with a charge tag (tag possessing a charge) prior to detection by mass spectrometry.

Abstract: Ultrasensitive detection of a chemical substance (analyte) by mass spectrometry is achieved by employing a molecular tag that yields an intense parent ion and then an intense daughter ion in a multi-stage mass spectrometer.

Abstract: Analytical chemical reagents termed non-signal imidazoles and a method for their use that provide a host of advantages for analysis of phosphomonoesters are described. The method and compounds of the invention provide a host of advantages for the analysis of phosphomonoester-containing compounds, namely characteristic, multi-analyte detection with high sensitivity and specificity of known and unknown phosphomonoester-compounds simultaneously.

Abstract: Ultrasensitive detection of a chemical substance (analyte) by mass spectrometry is achieved by employing a molecular tag that yields an intense parent ion and then an intense daughter ion in a multi-stage mass spectrometer.

Abstract: Ultrasensitive detection of a chemical substance (analyte) by mass spectrometry is achieved by employing a molecular tag that yields an intense parent ion and then an intense daughter ion in a multi-stage mass spectrometer.

Abstract: Secondary amide xanthene derivatives, termed “xanthamides”, and other xanthene derivatives, are obtained in one form as fluorescent dyes which can have much higher photostability than related dyes such as fluorescein and BODIPY-FL. Examples are presented in which the synthesis begins with 5-carboxyfluorescein, an inexpensive reagent. Related carboxyxanthenes employed in other dyes such as rhodamines can also be used as starting materials. Simple synthetic steps yield compounds which exemplify this invention. Other notable properties of the xanthamide dyes include the option of pH-independent fluorescence, and the ease of controlling their functional and other groups. This means that a diversity of xanthamide and related xanthene dyes can be prepared with a broad variation of physicochemical properties to enhance the usefulness of fluorescence in biological and chemical analysis, and in other areas.