Techniques are described for quantification of molecules in a sample. Mass spectrometry is performed to obtain ionization intensities for precursor and product ions originating from a particular molecule. A first stet of precursor ions having the highest ionization intensities and originating from the particular molecule is determined. For each of the one or precursors in the first set, determined is a second set of one or more product ions that are fragments associated with said each precursor and have the highest ionization in intensities of product ions associated with said each precursor. An intensity sum is calculated for the particular molecule by adding ionization intensities of product ions included in the second sets for the one or more precursors in the first set. The intensity sum is compared to information included in a calibration standard. A quantity of the particular molecule in the sample is determined based on said comparing.

An automated method of monitoring a state of an analyzer is provided including a mass spectrometer (MS) with an electrospray ionization (ESI) source coupled to a liquid chromatography (LC) stream, including monitoring an electrospray ionization current of the ESI source and identifying a condition of multiple conditions of the analyzer based on the monitored ionization current of the ESI source, one of the conditions being a presence of a dead volume in a liquid chromatography stream of the analyzer downstream of an LC column of the LC stream.

This disclosure provides ten (10) specific peptides, and particular peptide characteristics, from the cell membrane-bound Her2 protein and a diagnostic assay useful for determining the presence and amount of full length and truncated versions of the full-length Her2 protein in cells derived from formalin fixed paraffin embedded tissue.

An object of the invention is to provide a mass spectrometry apparatus capable of obtaining a highly accurate quantitative result and being low-cost. A small section measurement instruction unit 101 instructs a detector 9 to perform measurement on a plurality of small sections 5 in a channel 4, the signals detected by the detector 9 are stored in a data storage unit 102, the signals are integrated by a small section signal amount integration unit 103, and variance of the integrated signals is calculated by a signal variance calculation unit 104. A signal variance evaluation unit 105 evaluates the signal variance of signals of each small section 5 in the same channel 4. When the signal variance is evaluated to be stable, an operation control unit 106 controls operations of the ion source 6 to continue measurement without warning. When the signal variance is evaluated to be unstable, the warning is performed during the measurement or after the measurement.

The invention relates to the detection of vitamin D metabolites. In a particular aspect, the invention relates to methods for detecting derivatized vitamin D metabolites by mass spectrometry.

A sample extraction device and a desorption device for use in gas chromatography (GC), gas chromatography-mass spectrometry (GCMS), liquid chromatography (LC), and/or liquid chromatography-mass spectrometry (LCMS) are disclosed. In some examples, the sample extraction device includes a lower chamber holding a sorbent. The sample extraction device can extract sample headspace gas from a sample vial by placing the sorbent inside the vial and creating a vacuum to increase recovery of low volatility compounds, for example. Once the sample has been collected, the sample extraction device can be inserted into a desorption device. The desorption device can control the flow of a carrier fluid (e.g., a liquid or a gas) through the sorbent containing the sample and into a pre-column and/or a primary column of a chemical analysis device for performing GC, GCMS, LC, LCMS, and/or some other chemical analysis process.

An improved analytical method for analysis of dianhydrogalactitol preparations provides a method for determining the purity of dianhydrogalactitol and detecting impurities in preparations of dianhydrogalactitol, as well as identifying any such impurities. The method employs high performance liquid chromatography (HPLC), in particular, HPLC with evaporative light scattering detection (ELSD); the HPLC can be followed by tandem mass spectroscopy. The method can further comprise the step of performing preparative HPLC collection of at least one specific substance peak present in a preparation of dianhydrogalactitol.

A gas chromatographic method for detecting a marker compound in a fuel by (a) introducing a sample of fuel into a first capillary column coated with a stationary phase based on polydimethylsiloxane and allowing the sample to flow through the first column to produce a first effluent; (b) allowing the first effluent to pass through a detector and identifying a retention time range in it which includes a retention time of the marker compound; (c) introducing only a portion of the first effluent stream which is within the retention time range into a second capillary column coated with either (i) an ionic sorbent or (ii) a polyethylene glycol, and allowing said portion to flow through the second capillary column to produce a second effluent stream; and (d) allowing the second effluent to pass through a detector; wherein the marker compound has formula Ar(R.sup.2).sub.m(OR.sup.1).sub.n and is present in the fuel at a level from 0.01 ppm to 100 ppm.

[Problem] To provide a mass spectrometry method that uses a chromatography-mass spectrometry device, wherein mass spectrometry can be performed with a convenient method at low cost. [Solution] A mass spectrometry method for a target object, using a chromatography-mass spectrometry device that includes, in order, a chromatograph, an ionization unit, a first mass separation unit, a collision cell, a second mass separation unit, and an ion detection unit, wherein an ion pair agent and Hünig's base are added to a mobile phase of the chromatograph, and the absolute value of an applied voltage of the collision cell is 20V to 250V.

The present disclosure relates to a method for providing diagnostic information for biliary tract cancer and an apparatus for diagnosing biliary tract cancer. According to an aspect of the present disclosure, there is provided a method for providing diagnostic information for biliary tract cancer including obtaining biological samples; measuring concentration of a marker for predicting biliary tract cancer in the biological samples; and providing diagnostic information for biliary tract cancer using the measured concentration of the marker, where the marker includes Nudifloramide.