提出了具有电荷转移解离质谱(CTD-MS)的超高效液相色谱(UHPLC),用于分析复合硫酸化寡糖的混合物。该混合物含有κ(κ),iota(i),和含有脱水桥的λ(λ)角叉菜胶,每个二聚体的硫酸化程度从一到三,硫酸基团在主链上的不同位置,和不同的聚合度(DP)在4和12之间。使用角叉菜胶标准混合物的优化研究有助于建立在线UHPLC-CTD-MS/MS分析的最佳条件。优化包括(1)UHPLC条件;(2)离子源条件,如毛细管电压,干燥气体和雾化气体温度,和流量;和(3)CTD-MS条件,包括数据依赖性CTD-MS。将UHPLC-CTD结果与相同仪器上相同混合物的UHPLC-CID结果进行对比。其中CID倾向于产生具有许多中性损失的B/Y和C/Z离子,CTD产生更丰富的A/X离子和更少丰富的中性损失,这使得结构细节更加自信。结果证明He-CTD与UHPLC的时间尺度相容,并且与现有技术方法如UHPLC-CID分析相比提供更多关于角叉菜胶的结构信息。
Ultra-high-performance liquid chromatography (UHPLC) with charge transfer dissociation mass spectrometry (CTD-MS) is presented for the analysis of a mixture of complex sulfated oligosaccharides. The mixture contained kappa (κ), iota (ι), and lambda (λ) carrageenans that contain anhydro bridges, different degrees of sulfation ranging from one to three per dimer, different positioning of the sulfate groups along the backbone, and varying degrees of polymerization (DP) between 4 and 12. Optimization studies using standard mixtures of carrageenans helped establish the optimal conditions for online UHPLC-CTD-MS/MS analysis. Optimization included (1) UHPLC conditions; (2) ion source conditions, such as the capillary voltage, drying gas and nebulizing gas temperature, and flow rate; and (3) CTD-MS conditions, including data-dependent CTD-MS. The UHPLC-CTD results were contrasted with UHPLC-CID results of the same mixture on the same instrument. Whereas CID tends to produce B/Y and C/Z ions with many neutral losses, CTD produced more abundant A/X ions and less abundant neutral losses, which enabled more confident structural detail. The results demonstrate that He-CTD is compatible with the timescale of UHPLC and provides more structural information about carrageenans compared to state-of-the-art methods like UHPLC-CID analysis.