کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
867820 909793 2011 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Improved bacteria detection by coupling magneto-immunocapture and amperometry at flow-channel microband electrodes
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Improved bacteria detection by coupling magneto-immunocapture and amperometry at flow-channel microband electrodes
چکیده انگلیسی

This paper describes the first immunosensing system reported for the detection of bacteria combining immunomagnetic capture and amperometric detection in a one-step sandwich format, and in a microfluidic environment. Detection is based on the electrochemical monitoring of the activity of horseradish peroxidase (HRP), an enzyme label, through its catalysis of hydrogen peroxide (H2O2) in the presence of the mediator hydroquinone (HQ). The enzymatic reaction takes place in an incubation micro-chamber where the magnetic particles (MPs) are confined, upstream from the working electrode. The enzyme product is then pumped along a microchannel, where it is amperometrically detected by a set of microelectrodes. This design avoids direct contact of the biocomponents with the electrode, which lowers the risk of electrode fouling. The whole assay can be completed in 1 h. The experiments performed with Escherichia coli evidenced a linear response for concentrations ranging 102–108 cell ml−1, with a limit of detection of 55 cells ml−1 in PBS, without pre-enrichment steps. Furthermore, 100 cells ml−1 could be detected in milk, and with negligible interference by non-target bacteria such as Pseudomonas.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biosensors and Bioelectronics - Volume 26, Issue 8, 15 April 2011, Pages 3633–3640
نویسندگان
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