title: Comparison of A+T-rich oligonucleotides with and without self-complementary sequence using ion-pair reversed-phase high-performance liquid chromatography/tandem electrospray ionization mass spectrometry.
abstract: Both A+T-rich oligonucleotides with and without self-complementary sequences were analyzed using ion- pair reversed-phase liquid chromatography/electrospray ionization mass spectrometry (IP-RP-HPLC/ESI-MS) by tryethylammonium acetate (TEAA) and hexafluoroisopropanol (HFIP) buffer systems to study the characteristics of their retention behavior and electrospray ionization tandem mass spectrometry (ESI-MS/MS) response. The results indicated that the chain length had the same effect on the retention of A+T-rich oligonucleotides in both of TEAA and HFIP buffer systems but the sequence had a different impact on the retention in the two buffer systems. A+T- rich oligonucleotides with a self-complementary sequence were much shorter than those without in the TEAA buffer system whereas a slight difference was observed in the HFIP buffer system. Similar total ion current (TIC) intensity was observed both in oligonucleotides with or without self-complementary sequence. The opposite trend of a change in the TIC intensities with increasing chain length were observed in both the TEAA and HFIP buffer systems. A lower charge state was predominant in the TEAA buffer system whereas a higher charge state was mainly distributed in the HFIP buffer system. The oligonucleotides without self-complementary sequences had a higher charge state than those with self-complementary sequences. A- and T- are more esily formed at a higher charge state whereas the sequence fragments will be formed more easily at a lower charge state in both A+T-rich oligonucleotides with and without self-complementary sequences.
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Research Center of Mass Spectrometry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Renfang
authors.initials: R
authors.lastname: Song
authors.forename: Wenbing
authors.initials: W
authors.lastname: Zhang
authors.forename: Huayong
authors.initials: H
authors.lastname: Chen
authors.forename: Huimin
authors.initials: H
authors.lastname: Ma
authors.forename: Yulian
authors.initials: Y
authors.lastname: Dong
authors.forename: Guoying
authors.initials: G
authors.lastname: Sheng
authors.forename: Zhen
authors.initials: Z
authors.lastname: Zhou
authors.forename: Jiamo
authors.initials: J
authors.lastname: Fu
mesh_terms: D020856:AT Rich Sequence; D002021:Buffers; D002851:Chromatography, High Pressure Liquid; D004563:Electrochemistry; D009841:Oligonucleotides / Q000032:analysis* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D002021:Buffers; D009841:Oligonucleotides