Nanobioengineering Group, Institute for Bioengineering of Catalonia (IBEC), Baldiri Reixac 10-12, 08028 Barcelona, Spain.
Biosens Bioelectron. 2013 Jul 15;45:174-80. doi: 10.1016/j.bios.2013.01.009. Epub 2013 Jan 29.
The presence of enterohemorrhagic Escherichia coli bacteria in food can cause serious foodborne disease outbreaks. Early detection and identification of these pathogens is extremely important for public health and safety. Here we present a highly sensitive label-free immunosensor for the detection of pathogenic E. coli O157:H7. Anti-E. coli antibodies were covalently immobilised onto gold electrodes via a self-assembled monolayer (SAM) of mercaptohexadecanoic acid and the pathogenic bacteria were detected by electrochemical impedance spectroscopy (EIS). Surface Plasmon Resonance (SPR) was used to monitor the antibody immobilisation protocol and antibody patterned surfaces were used to demonstrate the specificity of the antibody coated surfaces against the pathogenic bacteria. The immunosensor showed a very low limit of detection (2CFU/mL) and a large linear range (3 × 10-3 × 10(4)CFU/mL). Finally, the selectivity of the sensor was demonstrated and no significant adsorption of Salmonella typhimurium was observed.
肠出血性大肠杆菌细菌存在于食物中会导致严重的食源性疾病爆发。对这些病原体的早期检测和鉴定对公众健康和安全至关重要。在这里，我们提出了一种用于检测致病性大肠杆菌 O157：H7 的高灵敏度无标记免疫传感器。通过巯基十六烷酸的自组装单层（SAM）将抗大肠杆菌抗体共价固定在金电极上，并通过电化学阻抗谱（EIS）检测病原菌。表面等离子体共振（SPR）用于监测抗体固定化方案，并使用抗体图案化表面来证明抗体涂覆表面对病原菌的特异性。该免疫传感器的检测限非常低（2CFU/mL），线性范围很大（3×10-3×10(4)CFU/mL）。最后，证明了传感器的选择性，并且没有观察到鼠伤寒沙门氏菌的显著吸附。
