• 분석과학
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• 제21권4호
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• pp.245-258
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• 2008

본 연구에서는 하고초의 지표성분인 triterpenic acids 5종을 컬럼 크로마토그래피와 역상 HPLC를 이용하여 추출 및 분리했고, 이들 성분의 순도는 90% 이상임을 HPLC를 이용하여 확인했다. 고속원자충돌 이온화법-고분해능 질량분석기(FAB-HRMS)를 사용하여 지표성분의 분자량 및 원소조성을 결정했으며, 지표성분의 구조 분석은 FAB-MS/MS 의해 음이온 및 양이온 모드에서 수행하였다. Triterpenic acid류의 충돌유발분해(collision-induced dissociation, CID) 탄뎀질량분석(MS/MS) 스펙트럼에서 protonated molecule인 $[M+H]^+$ 및 deprotonated molecule인 $[M-H]^-$ 이온의 CID는 주로 retro Diels-Alder (RDA), 탈수 (dehydration) 및 탈탄산(decarboxylation) 반응에 의한 다양한 생성이온들이 나타났다. 특히, $[M-H]^-$이온의 CID-MS/MS 스펙트럼에서는 charge-remote fragmentation (CRF) 현상에 의한 이온들도 특성이온으로 나타났다. 이들 CID-MS/MS 스펙트럼의 해석을 통하여 하고초의 지표성분인 triterpenic acids의 구조 규명을 수행하였다.

• Bulletin of the Korean Chemical Society
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• 제18권8호
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• pp.874-880
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• 1997

Various classes of phospholipids were investigated for the structural determination of fatty acyl groups by fast atom bombardment tandem mass spectrometry (FAB-MS/MS). Phospholipids were desorbed by FAB as molecules chelated with sodium ion (or ions). Collision-induced dissociation (CID) of intact sodium adduct molecular ions ([M+Na]+, [M-H+2Na]+ or [M+Na-2H]-) produced a series of homologous fragment ions via the charge-remote fragmentation along the fatty acid chains. These ions were found useful to locate the double bond positions even for the polyunsaturated fatty acid chains. The regiospecificity of the acyl chain linkages in phosphatidylcholine (PC) could also be determined based on the ratio of relative abundance of the product ions (i.e., [M+Na-85-R2COOH]+ vs [M+Na-85-R1COOH]+) in CID-MS/MS of [M+Na]+. These are generated by the loss of fatty acyl groups at sn-1 and sn-2, respectively, together with the choline group. In all the phospholipid compounds investigated, loss of the fatty acid at the sn-2 position was dominant. The present method was applied to the structural determination of molecular species of phosphatidylglycerols (PG) isolated from cyanobacterium Synechocystis sp. PCC 6803.

• Mass Spectrometry Letters
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• 제2권1호
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• pp.8-11
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• 2011

Two types of glycerolipids [monoacylglycerols (MAG) and cyclitols] were isolated by reversed phase high-performance liquid chromatography from the methanol extracts of a marine sponge, and analyzed by fast atom bombardment mass spectrometry (FAB-MS) in positive-ion mode. FAB mass spectra of these compounds yielded protonated molecules $[M + H]^+$ and abundant sodiated molecules $[M + Na]^+$ from a mixture of 3-nitrobenzyl alcohol and NaI. The structures of these compounds were elucidated by FAB-collisional-induced dissociation (CID)-tandem mass spectrometry. We carried out collision-indused dissociation (CID) of these lipids in B/E-linked scan mode. The CID B/E-linked scan of $[M + H]^+$ and $[M + Na]^+$ precursor ions resulted in the formation of numerous characteristic product ions through a series of dissociative processes. The product ions formed by charge-remote fragmentation (CRF) provided important information for the identification of the acyl chain structure substituted at the glycerol backbone. Some of the product the ions were diagnostic for the presence of a glycerol backbone or acyl chain structure.