Process mass spectrometry, analytical method

To examine a sample by inductively coupled plasma mass spectrometry (ICP/MS) or inductively coupled plasma atomic-emission spectroscopy (ICP/AES) the sample must be transported into the flame of a plasma torch. Once in the flame, sample molecules are literally ripped apart to form ions of their constituent elements. These fragmentation and ionization processes are described in Chapters 6 and 14. To introduce samples into the center of the (plasma) flame, they must be transported there as gases, as finely dispersed droplets of a solution, or as fine particulate matter. The various methods of sample introduction are described here in three parts — A, B, and C Chapters 15, 16, and 17 — to cover gases, solutions (liquids), and solids. Some types of sample inlets are multipurpose and can be used with gases and liquids or with liquids and solids, but others have been designed specifically for only one kind of analysis. However, the principles governing the operation of inlet systems fall into a small number of categories. This chapter discusses specifically substances that are normally liquids at ambient temperatures. This sort of inlet is the commonest in analytical work. 

For many years, electron ionization, then more usually known as electron impact, was the only ionization method used in analytical mass spectrometry and the spectra encountered showed exclusively the positively charged species produced during this process. Electron ionization also produces negatively charged ions although these are not usually of interest as they have almost no structural significance. Other ionization techniques, such as Cl, FAB, thermospray, electrospray and APCI, however, can be made to yield negative ions which are of analytical utility. 

Electrospray ionization occurs by the same four steps as listed above for thermospray (see Section 4.6). In contrast to thermospray, and most other ionization methods nsed in mass spectrometry, it shonld be noted that electrospray ionization nnnsnally takes place at atmospheric pressure. A similar process carried out under vacuum is known as electrohydrodynamic ionization and gives rise to qnite different analytical results. This technique has not been developed into a commercial LC-MS interface and will not be considered further. 

In order to understand the removal of FMs during wastewater treatment, it is necessary to measure these compounds throughout the wastewater treatment process. Because of the complex nature of wastewater matrices and the low concentration of FMs (0.001-60 pg/L) [11] throughout the treatment plant, accurate and sensitive analytical methods have been developed by a number of researchers. Fortunately, the analytical techniques developed to measure traditional SOCs, such as solvent extraction, extract concentration, and analysis by gas chromatography-mass spectrometry, in general also apply to FMs. 

Recent advances in mass spectrometry (MS) techniques have radically changed the analysis of biomolecules. MS has become the analytical method of choice for discovery and characterization of molecules with therapeutic value. Technological breakthroughs in the discovery area are now increasingly applied in the process development held and have recently entered the production process in manufacturing and quality control (QC) areas. In this presentation, after a review of the current state of the art, we would like to demonstrate how MS methods are influencing the development and manufacturing of therapeutic molecules. 

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