Reschiglian Pierluigi, Zattoni Andrea, Cinque Leonardo, Roda Barbara, Dal Piaz Fabrizio, Roda Aldo, Moon Myeong Hee, Min Byung Ryul
Department of Chemistry G. Ciamician, University of Bologna, Via Selmi 2, I-40126 Bologna, Italy.
Anal Chem. 2004 Apr 1;76(7):2103-11. doi: 10.1021/ac0353379.
This work proposes for the first time the use of hollow-fiber flow field-flow fractionation (HF FlFFF) for improved matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI/TOFMS) of whole bacteria. HF FlFFF has proved to be able to prepurify or fractionate different species of whole bacteria. Sample preparation by HF FlFFF gives improved spectra quality because noncellular components possibly present in the sample can be separated from the cells. When a mixture of two bacteria (Bacillus subtilis and Escherichia coli) is fractionated through HF FlFFF, MALDI/TOFMS analysis of each separated bacterial species preserves the most characteristic ion signals of the species without the presence of characteristic signals of the other species. The main advantages of HF FlFFF for MALDI/TOFMS analysis of whole bacteria are miniaturization, simplicity, and low cost of the fractionator components. This low cost makes disposable usage of the fractionator possible, thus eliminating the risk of run-to-run contamination of spectra due to sample carryover. The low fractionator volume yields bacterial fractionation on the order of a few minutes, which is comparable to MALDI/TOFMS analysis time. The small fractionation volume makes sample dilution low enough so that additional sample concentration steps are not strictly required to preserve MALDI/TOFMS detection.
这项工作首次提出使用中空纤维流动场-流分级法（HF FlFFF）来改进全细菌的基质辅助激光解吸/电离飞行时间质谱（MALDI/TOFMS）分析。事实证明，HF FlFFF能够对不同种类的全细菌进行预纯化或分级分离。通过HF FlFFF进行样品制备可提高光谱质量，因为样品中可能存在的非细胞成分可以与细胞分离。当通过HF FlFFF对两种细菌（枯草芽孢杆菌和大肠杆菌）的混合物进行分级分离时，对每种分离出的细菌进行MALDI/TOFMS分析时，该菌种保留了其最具特征性的离子信号，而没有其他菌种的特征信号。HF FlFFF用于全细菌MALDI/TOFMS分析的主要优点是分级仪组件小型化、操作简单且成本低。这种低成本使得分级仪可以一次性使用，从而消除了由于样品残留导致的不同批次光谱间污染的风险。分级仪体积小，可在几分钟内完成细菌分级分离，这与MALDI/TOFMS分析时间相当。分级分离体积小使得样品稀释程度足够低，因此不需要严格进行额外的样品浓缩步骤来维持MALDI/TOFMS检测。
