Reaction interfaces, mass spectrometry

Lecchi, P. and Abramson, F. P., Size exclusion chromatography-chemical reaction interface mass spectrometry a perfect match, Anal. Chem., 71, 2951, 1999. 

CA Goldthwaite Jr, F-Y Hsieh, SW Womble, BJ Nobes, IA Blair, LJ Klunk, RF Mayol. Liquid chromatography/chemical reaction interface mass spectrometry as an alternative to radioisotopes for quantitative drug metabolism studies. Anal Chem 68 2996-3001, 1996. 

A. Chemical Reaction Interface Mass Spectrometry (CRIMS)... 

FP Abramson. CRIMS—chemical reaction interface mass spectrometry. Adv Mass Spectrom 13 341, 1994. 

H Song, FP Abramson. Selective detection of chlorine-containing compounds by gas chromatography/chemical reaction interface mass spectrometry. Anal Chem 65 447, 1993. 

JJ Kusmierz, FP Abramson. Tracing 15N with chemical reaction interface mass spectrometry A demonstration using 15N-labeled glutamine and asparagine substrates in cell culture. Biol Mass Spectrom 23 756, 1994. 

F-Y Hsieh Jr, CA Goldthwaite, BJ Nobes, RF Mayol, LJ Klunk, IA Blair. Quantification of drug metabolism using a combination of chemical reaction interface mass spectrometry and NMR. Proc 42nd ASMS Conf on Mass Spectrometry and Allied Topics, 1994, p. 615. 

Teffera, Y. Abramson, F. Application of high-performance liquid chromatography/chemical reaction interface mass spectrometry for the analysis of conjugated metabolites a demonstration using deu-terated acetaminophen. Biol.Mass.Spectrom., 1994, 23, 776—783... 

Mass spectrometric approaches are also very useful for the measurement of stable isotopes in drug metabolism studies. The application of MS to the quantitative measurement of stable isotope has been limited due to the high cost and sophistication of the instruments necessary for stable isotope enrichment studies. Nonetheless, recent improvements in instrument design and performance, as well as computer software for instrument control, data acquisition, and analysis, have increased the sensitivity and reliability of stable isotopic enrichment studies. These new MS instruments, including continuous-flow isotope ratio mass spectrometry (CF-IRMS) and HPLC-chemical reaction interface mass spectrometry (HPLC-CRIMS) are increasingly less expensive, easier to operate, and accessible for mass balance/ metabolite identification studies with stable isotopes. 

Surface analysis has made enormous contributions to the field of adhesion science. It enabled investigators to probe fundamental aspects of adhesion such as the composition of anodic oxides on metals, the surface composition of polymers that have been pretreated by etching, the nature of reactions occurring at the interface between a primer and a substrate or between a primer and an adhesive, and the orientation of molecules adsorbed onto substrates. Surface analysis has also enabled adhesion scientists to determine the mechanisms responsible for failure of adhesive bonds, especially after exposure to aggressive environments. The objective of this chapter is to review the principals of surface analysis techniques including attenuated total reflection (ATR) and reflection-absorption (RAIR) infrared spectroscopy. X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), and secondary ion mass spectrometry (SIMS) and to present examples of the application of each technique to important problems in adhesion science. 

The method for chloroacetanilide soil metabolites in water determines concentrations of ethanesulfonic acid (ESA) and oxanilic acid (OXA) metabolites of alachlor, acetochlor, and metolachlor in surface water and groundwater samples by direct aqueous injection LC/MS/MS. After injection, compounds are separated by reversed-phase HPLC and introduced into the mass spectrometer with a TurboIonSpray atmospheric pressure ionization (API) interface. Using direct aqueous injection without prior SPE and/or concentration minimizes losses and greatly simplifies the analytical procedure. Standard addition experiments can be used to check for matrix effects. With multiple-reaction monitoring in the negative electrospray ionization mode, LC/MS/MS provides superior specificity and sensitivity compared with conventional liquid chromatography/mass spectrometry (LC/MS) or liquid chromatography/ultraviolet detection (LC/UV), and the need for a confirmatory method is eliminated. In summary,... 

Authenticity evaluation has recently received increased attention in a number of industries. The complex mixtures involved often require very high resolution analyses and, in the case of determining the authenticity of natural products, very accurate determination of enantiomeric purity. Juchelka et al. have described a method for the authenticity determination of natural products which uses a combination of enantioselective multidimensional gas chromatography with isotope ratio mass spectrometry (28). In isotope ratio mass spectrometry, combustion analysis is combined with mass spectrometry, and the 13C/12C ratio of the analyte is measured versus a C02 reference standard. A special interface, employing the necessary oxidation and reduction reaction chambers and a water separator, was used employed. For standards of 5-nonanone, menthol and (R)-y-decalactone, they were able to determine the correct 12C/13C ratios, with relatively little sample preparation. The technical details of multidimensional GC-isotope ratio MS have been described fully by Nitz et al. (29). A MDGC-IRMS separation of a natural ds-3-hexen-l-ol fraction is... 

This system is a rapid-serial primary screen. It uses a probe to scan from sample to sample across a catalyst wafer, analyzing reaction products at each location via mass spectrometry and/or optical absorption [1, 2, 45, 46]. The mass spectrometer is a commercial quadruple system with a custom ionizer interface. The optical absorption cell is a custom device and uses the method of photo-thermal deflection (mirage) to measure very low levels of a specific analyte. 

---