Mass spectrometry (MS) is an important tool for analyzing or detecting a wide range of organic, inorganic, natural, unnatural molecules, especially drugs, proteins, peptides are of interests beside routine analysis [1]. MS measures the mass-to-charge ratios of ions of an ionized sample, which may be gas, liquid or solids. Mass-to-charge ratios may obtain for a charged molecule or charged fragments. MS has both quantitative and qualitative uses. Numerous ionization methods are used in MS experiments, such as chemical ionization (CI), matrix assisted laser desorption ionization (MALDI), electron impact (EI), atmospheric pressure chemical ionization (APCI), and electrospray ionization (ESI). ESI-MS has been applied to the analysis of oligonucleotides [2, 3] drugs and drug metabolites [4] oligosaccharides [5, 6] environmental contaminants [7, 8] glycoproteins [9] and many other types of compounds [10-15]. In atmospheric pressure ion sources, e.g., ESI or APCI, dissociation of ions can occur inside the ionization source (source induced dissociation; SID) before reaching the mass analyzer. SID has been used by several research groups [16-22]. Usually, SID is used to analyze single mass, whereas CID is used to analyze fragmentation. Both SID and CID techniques having

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