Rapid identification of Escherichia coli and Helicobacter pylori in biological samples by capillary zone electrophoresis

Abstract

The differences in surface charge of different bacteria can be exploited for their separation by capillary electrophoresis. However, this method of separation of microorganisms is beset with various drawbacks such as adhesion of bacteria to the fused silica surface or cluster formation. To overcome these phenomena we investigated the addition of poly(ethylene oxide) as a focusing agent to the running buffer and used calcium and myoinositol hexakisphosphate as specific ions that interact with the bacterial surface, changing its electrical properties and electrophoretic mobilities. In the present work, we applied CZE to identification of E. coli in infected urine (direct injection) from patients with urinary tract infections and to identification of Helicobacter pylori, which is a gram-negative bacillus responsible for one of the most common infections found in humans worldwide. Helicobacter pylori colonize the stomach and are responsible for severe diseases of the gastric tract, ranging from chronic gastric ulcer to gastric cancer.

Analysis of Bacillus globigii spores by CE

“…3 show many random spikes along with the peaks attributable to dye-spore, dye-homoserine, and dye-HSA complexes. Previous studies show that the addition of PEO to the separation buffer can serve to dissipate large aggregates [19,21,24,67,68], although some may still exist and may result in light scattering events seen as random spikes in the fluorescence signal. Spikes in an electropherogram can also be the result of air trapped within a sample matrix.…”

Determination of pathogenic bacteria by CZE with surface‐modified capillaries

“…Similar results were obained in our previous study for different sepecies of bacteria. For example, we are able to separate two different clinical strains of H. pylori in a single run [38][39][40][41].…”

“…H. pylori colonizes the stomach and is responsible for severe diseases of the gastric tract ranging from chronic gastric ulcer to gastric cancer. Using dynamical modification of internal capillary surface they were able to resolve different clinical strains of the same species of H. pylori collected from patients with ulcers [39,41]. Therefore, CE should help in appropriate diagnosis of the disease and the choice of the most suitable therapy [40].…”

Detection of microbial food contaminants and their products by capillary electromigration techniques

“…In successive years, several laboratories directed their studies toward the analysis of microorganisms with interest in food industry, clinical diagnosis and environmental control, using diluted polymer-based BGEs [44][45][46][47][48][49][50]. Shintani et al [44] successfully detected Salmonella enteritidis, the causative agent of a major foodborne disease, by CE and the aid of UV and LIF detectors.…”

“…At such buffer concentration, the mobility of the microorganisms decreased but the bacterial cells resisted decomposition and therefore, no extra significant noise or unwanted peaks were detected in the electrophoregrams. More recently, Klodzinska et al [50] have investigated the use of diluted PEObased BGEs for the rapid identification of E. coli and the emerging pathogen Helicobacter pylori in complex samples.…”