Identification mass spectroscopy

Polyester composition can be determined by hydrolytic depolymerization followed by gas chromatography (28) to analyze for monomers, comonomers, oligomers, and other components including side-reaction products (ie, DEG, vinyl groups, aldehydes), plasticizers, and finishes. Mass spectroscopy and infrared spectroscopy can provide valuable composition information, including end group analysis (47,101,102). X-ray fluorescence is commonly used to determine metals content of polymers, from sources including catalysts, delusterants, or tracer materials added for fiber identification purposes (28,102,103). 

The field of steroid analysis includes identification of steroids in biological samples, analysis of pharmaceutical formulations, and elucidation of steroid stmctures. Many different analytical methods, such as ultraviolet (uv) spectroscopy, infrared (ir) spectroscopy, nuclear magnetic resonance (nmr) spectroscopy, x-ray crystallography, and mass spectroscopy, are used for steroid analysis. The constant development of these analytical techniques has stimulated the advancement of steroid analysis. 

Phenethyl alcohol may be identified as the phenethyl -nitrobenzoate [57455-00-2] (mp 106—108°C), as phenethyl -nitrobenzyl phthalate [65997-34-4] (mp 84.3°C), and also by its formation of styrene on treatment with alkaU. Use of these derivatives has, however, been superseded by physical methods. Infrared (75,76), mass spectroscopy (77), and nmr spectra (78) are useful for identification. 

There are many reports of the use of mass spectroscopy coupled to chromatography outlets for detection and identification of dmgs and metabolites. An example is compound 126 (99MI2, 99MI3). Carboxylic acids have been converted into hydrazides and hence into 3-substituted [l,2,4]triazolo... 

Computational methods including both metabolism databases and predictive metabolism software can be used to aid bioanalytical groups in suggesting all possible potential metabolite masses before identification by mass spectroscopy (MS) [116,117]. This approach can also combine specialized MS spectra feature prediction software that will use the outputs from databases and prediction software and make comparisons with the molecular masses observed... 

Johnson SK, LL Honk, J Feng, RS Honk, DS Johnson (1999) Electrochemical incineration of 4-chlorophenol and the identification of products and intermediates by mass spectroscopy. Environ Sci Technol 33 2638-2644. 

Rivera-PastarnaD, YahiaEM and Gonzalez-Aguilar G. 2009. Identification and quantification of carotenoids and phenolic compounds in papaya using mass spectroscopy. In preparation. 

Stintzing FC, Schieber A and Carle R. 2002. Identification of betalains from yellowbeet (beta vulgaris L.) and cactus pear (Opuntiaficus-indica L. Mill.) by high performance liquid chromatography-electrospray ionization mass spectroscopy. J Agric Food Chem 50 2302—2307. 

S. Suwanrumpha, R. B. Freas, Identification of Metabolites of Ampicillin Using Liquid Chromatography/Thermospray Mass Spectrometry and Fast Atom Bombardment Tandem Mass Spectroscopy , Biomed. Environ. Mass Spectrom. 1989, 18, 983-994. 

J. E. Pitts, R. B. Bruce, J. B. Forehand, Identification of Doxapram Metabolites Using High Pressure Ion Exchange Chromatography and Mass Spectroscopy , Xenobiotica 1973, 3, 73-83. 

Mule SJ, Casella GA. (1988). Rendering the "poppy-seed defense" defenseless identification of 6-monoacetylmorphine in urine by gas chromatography/mass spectroscopy. Clin Chem. July 34 7 1427-30. 

This method suffered from sensitivity problems initially as the bile-acid molecules lack a chromophore, but did offer the distinct advantage that conjugated bile acids could be determined without hydrolysis. The sensitivity issue was addressed by use of fluorescent derivatives such as dimethoxycoumarin esters with a C18 reverse phase column and were able to resolve endogenous mixtures of bile acids. The combination of hplc and mass-spectroscopy detection has further improved the sensitivity along with providing specific identification, important as the resolution of bile acids by hplc is not as good as capillary column glc. ... 

---