Applications of LC/MS

Applications of LC/MS in Natural Products Analysis [ 下載 PDF ]

Chi-Chi Chou, Bing-Chung Liau, Wen-Lin Liu, Ting-Ting Jong, Maw-Rong Lee

The study of natural products in plant extracts is an interesting challenge to liquid chromatography/mass spectrometry (LC/MS). It has been important in the analysis of alkaloids and other plant-related compounds. In this article, LC/MS applications in the fields of analysis of natural products and endogenous compounds are reviewed.

LC/MS: A Key Instrument for Dietary Supplements Analysis [ 下載 PDF ]

Ren-Kun Chen, Ya-Hui Hou, Yong-Chien Ling

Dietary supplements usually contain complex matrix, which will severely interfere the ingredients determination. The powerful characterization technique of mass spectrometry (MS) coupled with efficient separation tool of high-performance liquid chromatography (LC) can play a key role for separating and identifying target compounds from complex mixtures. This article introduces the features of LC, ionization methods, mass analyzers, and popular commercial LC/MS first, followed by demonstrating with several real examples on dietary supplements analysis. The aim is to help the readers to effectively use LC/MS for dietary supplements analysis and research.

An Introduction to LC/MS in Food Analysis [ 下載 PDF ]

Shun-An Chan, Ti-Yu Wu, Ming-Ren Fuh

Food analysis is very important to the safety and health of general public. An accurate and sensitive analytical assay is essential to the success of this task. For food analysis, the complexity of sample matrix often interferes with the analysis. Furthermore, sensitivity is an important issue in the food analysis due to the minute amount of residue or additive in food. Recently, liquid chromatographymass spectrometry (LC/MS) has been proven to be a useful analytical tool for various applications. In this article, we briefly introduced some LC/MS applications for the food analysis: (1) LC/MS analysis of residual sulfonamides in meat, (2) LC/MS analysis of residual chloramphenicol in food stuff, (3) LC/MS analysis of protein and peptide in food. In addition, the advantages of LC/MS for the food analysis were discussed.

Microbial Identification Using High-Performance Liquid Chromatography-Mass Spectrometry [ 下載 PDF ]

Chi-Hung Wu, Yen-Peng Ho

High-performance liquid chromatography-mass spectrometry (LC-MS) is suitable for the identification of microorganisms. The technique is capable of performing sample clean-up, concentration, separation as well as structural characterization. Microorganisms can be differentiated or identified by the LC-MS analysis of biomarkers such as lipids and proteins. The microbial identification is based on the biomarker profiles or protein database search.

Applications of Liquid Chromatography-Mass Spectrometry in Environmental Analysis [ 下載 PDF ]

Chung-Yu Chen, Maw-Rong Lee

LC/MS plays an important role in the development of new analytical strategies for environmental analysis. This article reviews the applications of LC/MS in some of the field of environmental analysis including analysis of pesticides and herbicides in water, surfactants, sulfonamides, polycyclic aromatic hydrocarbons, dyes, as well as haloacetic acids analysis.

Applications of Liquid Chromatography-Mass Spectrometry in Cancer Risk Assessment: Analysis of DNA Adducts [ 下載 PDF ]

Hauh-Jyun Candy Chen

DNA adduct formation is involved in the initiation stage of carcinogenesis. Characterization and accurate quantification of DNA adducts are required for cancer risk assessment and the subsequent cancer prevention strategy. Highly specific and sensitive analytical methodologies are imperative for measurement of the ultratrace amounts of DNA adducts in the complex mixture of biological samples. This article reviews application of DNA adducts, especially etheno adducts and 8-oxopurine addcuts, by liquid chromatography coupled with tandem mass spectrometry and compared with other mass spectrometric assays. The physiological significance and implications of these DNA adducts are discussed.

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Application of Matrix-Assisted Laser Desorption Ionization Mass Spectrometry on Single Nucleotide Polymorphism Genotyping [ 下載 PDF ]

Yet-Ran Chen, Hsin-Kai Liao, Yu-Ju Chen

In postgenome era, DNA variation analysis is of great interest for providing insight into disease mechanism. Vast numbers of analysis to fully explore the genomic information have enabled the growing demand of high sensitivity, high throughput, and low cost platforms. By the intrinsic nature of accuracy, sensitivity and speed, matrix-assisted laser desorption / ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has emerged an important tool for genotyping. This review will focus on the latest methods for SNP genotyping using MALDI-TOF MS.

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Computational Analyses on System Performances of VCDi Undergoing Thermal Loadings [ 下載 PDF ]

Jyh-Jian Chen

The optical properties and physical dimensions of optical components change with temperature, and hence also do the characteristics of optical systems. The thermal control system of Vegetation and Change Detection imager was numerically analyzed in this work. The effects of temperature changes on the performance of this typical optical system were described in this paper. Whether their performance with or without heat sources at ambient conditions and the maximum operating temperature within the allowed tolerance was reported. While lens temperature is below 10 °C, there will be some liquid saturated on the lens without taken into drying processes in advance. A simple method is suggested to prevent the lens from saturation and condensation of water vapor.

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Gasdynamic Characteristics and Thermal-Flow Design of Metal Organic Chemical Vapor Deposition Reactors for Semiconductor Thin-Films [ 下載 PDF ]

Chyi-Yeou Soong

Metal organic chemical vapor deposition (MOCVD) or vapor phase epitaxy (MOVPE) is a critical process for preparation of compound semiconductor thin-films. Thermal-flow management in MOCVD reactors is one of the key factors for quality of the epilayer. In the present paper, thermal-flow management techniques of various MOCVD reactors and the mechanisms related to the epitaxial uniformity are manifested based on the gasdynamics viewpoint and the author’s recent investigations in this area. This special topic provides interdisciplinary background knowledge for design of MOCVD epitaxial facilities and for determination and modulation of the operating parameters as well. The flow-thermal-mass coupling mechanisms and solutions disclosed in the present paper are also useful to thermal-flow management or design for other electronic/mechanical facilities and instruments.

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Spindle Motor for High Density Disk Drive [ 下載 PDF ]

Chien-Chang Wang, Yeong Der Yao

Motors touch many aspects of our lives. The application of small-size electronic motors is almost everywhere in the world. We can always find one or several motors in many electronic consumers, such as each automobile contains dozens of motors. In modern history, we have witnessed the tremendous contribution of motors to improve our human life. Spindle motor is a key component in the hard disk drives of modern computers. In this report, we would like to review some of the recent research works related to spindle motor for high density disk drive, and to present a high efficiency spindle motor designed by us.

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Introduction of the Developing Technology of Electronic Tongue [ 下載 PDF ]

Ren-Jang Wu

The main application of electronic tongue is analysis for liquid sample, and the principle of electronic tongue is recognition of the signal pattern by the way of mimic human taste system. In recent decent the technology of electronic tongue is developed very fast in the world, also the basic study of the technology was established in Taiwan. This paper described the topic of electronic tongue, including introduction, principle, the condition of the under developing and future technology. Wish this work might be helpful for some researchers and interests.