Electrophore-labeling and alkylation of standards of nucleic acid pyrimidine bases for analysis by gas chromatography with electron-capture detection

Development of fast atom bombardment mass spectral methods for the identification of carcinogen-nucleoside adducts

“…Recent results from Schram's laboratory [32,33] show surprisingly low level detection for silylated derivatives of related compounds, including ribonucleosides and ribonucleotide monophosphate derivatives by FAS/MS. This approach is analogous to the electrophore derivatization methods used to enhance the detection of alkylated nucleosides and bases using NIO mass spectrometry [34], or electron capture GC [35].…”

GC-FID determination of nucleobases guanine, adenine, cytosine, and thymine from DNA by precolumn derivatization with isobutyl chloroformate

“…Now, comparing the present work with the reported GC procedures (Table 3) indicates that most of the reported procedures are based on precolumn derivatization with different silylation reagents, which requires nonaqueous media for their derivatization (Laking and Gehrke 1972;Nazareth et al 1984;Gelijkens et al 1981;Tekel et al 1998), whereas the present work is based on the use of aqueous-organic phase. The present method indicates comparable or better sensitivity with shorter retention times than the reported procedure.…”

“…Thus, derivatization is required before their determination. The derivatization reagents used include bis(trimethylsilyl) trifluoroacetamide (Kuhara et al 2011;Laking and Gehrke 1972); pentafluorobenzoyl chloride, pentafluorophenylsulfonyl chloride, or heptafluorobutyric anhydride (Nazareth et al 1984); N,N-tert-butyldimethylsilyl trifluoroacetamide (Glavin et al 2006); and N-(tert-butyl-dimethylsilyl) N-methyl trifluoroacetamide (Horst et al 2012). The silyl reagents are effective derivatizing reagents for nucleobases but require a nonaqueous medium for their derivatization.…”

Pentafluorobenzylation of O4-ethylthymidine and analogs by phase-transfer catalysis for determination by gas chromatography with electron capture detection

“…An extension of this method, termed neutralization-reionization mass spectrometry (NRMS) (3, 4) incorporates the methodology of Gellene and Porter (5) for the alternative preparation of the fast neutrals by charge exchange of mass-selected precursor ions. Similar experimental techniques have studied electron transfer and energy states of simple mono-to triatomic species such as H3 (5)(6)(7)(8)(9)(10). NRMS makes possible the preparation of neutral species whose reference reionization mass spectra can be directly compared to those of neutral dissociation products.…”