Microfluidic Chipshop, GmbH, Stockholmer Strasse, Jena 07747, Germany.
Anal Chem. 2017 Jun 20;89(12):6513-6520. doi: 10.1021/acs.analchem.7b00598. Epub 2017 Jun 6.
A counter-pressure-assisted capillary isotachophoresis method in combination with a sieving matrix and ionic spacer was used to perform in-line fluorescence in situ hybridization (FISH) of bacterial cells. A high concentration of sieving matrix (1.8% w/v HEC) was introduced at one end of the capillary, and the bacterial cells were suspended in the spacer electrolyte for injection. Using a 2 min injection with 18 psi counter-pressure, 50% of the cells injected into the capillary were hybridized with the fluorescently labeled oligonucleotide, and the excess unhybridized probe was separated from the hybridized cell-probe complexes in a two-stage ITP method. With an LOD (6.0 × 10 cells/mL) comparable with the CE analysis of a sample processed using an off-line FISH protocol, the total analysis time was reduced from 2.5 h to 30 min. Provided the appropriate probe is selected, this approach can be used for specific detection of bacterial cells in aqueous samples.
采用一种反压辅助的胶束电动毛细管电泳法，结合筛分基质和离子间隔物，对细菌细胞进行在线荧光原位杂交（FISH）。在毛细管的一端引入高浓度的筛分基质（1.8%w/v HEC），细菌细胞悬浮在间隔电解质中进行注射。通过 2 分钟、18psi 反压的注射，有 50%的注入细胞与荧光标记的寡核苷酸杂交，多余的未杂交探针在两步 ITP 方法中与杂交的细胞-探针复合物分离。与使用离线 FISH 方案处理的样品的 CE 分析的检测限（6.0×10^6 细胞/mL）相当，总分析时间从 2.5 小时缩短到 30 分钟。只要选择合适的探针，这种方法就可以用于在水样中对细菌细胞的特异性检测。
