Liquid chromatography-mass advantages

Liquid chromatography/mass spectrometry (LC/MS) is an analytical technique combining the advantages of an LC instrument with those of a mass spectrometer. 

TFA is advantageous in that it enhances the peak shape and efficiency for some polar compounds and its higher volatility is more desirable in liquid chromatography-mass spectrometry (LC-MS) operative conditions. The interfacing of LC methodologies with MS is discussed later in Section 2.3.1.4. 

Most of these measurements are still routinely perfonned with immunoassays because of their simplicity, rapidity and relatively low cost, and despite occasional concerns about their reliability and validity. Serum total T has also been quantitated by gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS) and LC-MS-MS. MS-based methods are often used in research smdies or to confirm immunoassay results. The advantage of chromatography coupled with MS is the high specificity not available with immunoassays because they are susceptible to cross-reactions. An immunoassay might measure a host of structurally related compounds in addition to the target analyte. 

Liquid chromatography-mass spectrometry (LC-MS) ideally combines advantages of the gentle separation of HPLC with high sensitivity and selectivity of mass spectrometry. There are two methods of ionization. The electrospray LC-MS ionization process can effectively transform the heterocychc amines from solution to protonated ions in the gas phase. The thermospray LC-MS ionization process produces abundant pseudo-molecular ions for this class of compounds. As a result, in both ionization processes the base peaks in the mass spectra are... 

Liquid chromatography-mass spectrometry (LC-MS) is a very promising analytical method for the MCs because it enables simultaneous separation and identification of cyanobacterial toxins in a mixture (Figure 40.2). Mass spectrometry, unlike UV spectroscopy, has the advantage that it can handle compounds that lack the UV chromophore. fit the case of MCs, the characteristic ion m/z 135 derived... 

In this frame, special procedures have been devised for the detection and quantification of specific products, including the development of fast and reliable liquid chromatography-mass spectrometry (LC-MS) methods that are also suitable for detecting multiple and simultaneous reactions at different amino acid side chains. These dedicated procedures are advantageous in that they may not involve the complete and time-consuming routine of hydrolysis and chromatography, but special attention must be paid to the standardization of the procedures, and to the presence of interfering materials. 

Stage that requires high efficiency as well as speed, due to the complexity of the sample matrix, and hence it is particularly challenging to achieve the goals. Therefore, the development of a rapid, sensitive, and reproducible method has been required for separation and determination of capsaicinoid compounds. The addition of ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) method fulfilled these aforementioned demands and showed some complementary advantages to the conventional HPLC-MS, u-HPLC methods in terms of shorter analysis times, low sample volume, and much improved sensitivity [71]. Therefore, nowadays this UPLC-MS technique is routinely performed in pharmaceutical industries and related contract research institutes, laboratories concerned with biochemistry, biotechnology, environmental analysis, natural product research, and several other research fields. The UPLC-MS method has successfully been applied for the determination of n-DHC, C, DHC, h-C, and h-DHC present in the varieties of hot peppers [71]. 

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