Methods for determining the amount of vitamin D compounds in a sample are provided. The methods can employ LC-MS/MS techniques and optionally the use of deuterated internal standards. Methods for diagnosing vitamin D deficiencies are also provided.

Provided are methods for determining the amount of lacosamide in a sample using mass spectrometry. The methods generally involve ionizing lacosamide in a sample and detecting and quantifying the amount of the ion to determine the amount of lacosamide in the sample.

Provided are methods of detecting the presence or amount of a dihydroxyvitamin D metabolite in a sample using mass spectrometry. The methods generally comprise ionizing a dihydorxyvitamin D metabolite in a sample and detecting the amount of the ion to determine the presence or amount of the vitamin D metabolite in the sample. In certain preferred embodiments the methods include immunopurifying the dihydroxyvitamin D metabolites prior to mass spectrometry. Also provided are methods to detect the presence or amount of two or more dihydroxyvitamin D metabolites in a single assay.

The invention relates to the detection of DHA and EPA. In a particular aspect, the invention relates to methods for detecting DHA and EPA by mass spectrometry and kits for carrying out such methods.

The invention generally relates to methods for rare event detection using mass tags. In certain embodiments, the invention provides methods for detecting a target analyte in a sample that involve conducting an assay that specifically associates a mass tag with a target analyte in a sample, generating ions of the mass tag, and analyzing the generated ions of the mass tag, thereby detecting the target analyte from the sample.

The invention generally relates to systems and methods for quantifying an analyte extracted from a sample. In certain embodiments, the invention provides methods that involve introducing a solvent into a capillary, introducing the capillary into a vessel including a sample such that a portion of the sample is introduced into the capillary, moving the sample and the solvent within the capillary to induce circulation within the sample and the solvent, thereby causing the analyte to be extracted from the sample and into the solvent, analyzing the analyte that has been extracted from the sample, and quantifying the analyte. In certain embodiments, the quantifying step is performed without knowledge of a volume of the sample and/or solvent.

The present invention is directed to a method and device to desorb an analyte using heat to allow desorption of the analyte molecules, where the desorbed analyte molecules are ionized with ambient temperature ionizing species. In various embodiments of the invention a current is passed through a mesh upon which the analyte molecules are present. The current heats the mesh and results in desorption of the analyte molecules which then interact with gas phase metastable neutral molecules or atoms to form analyte ions characteristic of the analyte molecules.

Provided are methods for determining the amount of lacosamide in a sample using mass spectrometry. The methods generally involve ionizing lacosamide in a sample and detecting and quantifying the amount of the ion to determine the amount of lacosamide in the sample.

Incendivity test systems and methods are disclosed. Incendivity test systems include a non-flammable gas mixture and a test article. The non-flammable gas mixture includes a thermally reactive reagent that is formulated to thermally react to produce a reaction product. Incendivity test systems also include an energy source configured to apply an energy discharge such as a simulated lightning strike to the test article. Incendivity test systems also include a detection device configured to measure an indicator species in the non-flammable gas mixture (e.g., the thermally reactive reagent and/or the reaction product). Incendivity test methods include contacting the test article with the non-flammable gas mixture, applying the energy discharge to the test article, and then measuring the amount of the indicator species and determining the incendivity of the test article in response to the energy discharge based upon the amount of the indicator species.

A sample preparation and analysis system. The system includes a sample preparation system and a sample analysis system. The sample preparation system prepares samples in accordance with an assay that is selected from a database containing a plurality of unique assays. The sample analysis system includes an analyzer that is dynamically reconfigurable based on the selected assay so as to analyze the prepared sample in accordance with that selected assay. A data communication link communicates data from the sample preparation system to the sample analysis system to reconfigure the analyzer in accordance with the selected assay.