کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
868565 909810 2010 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
An electrochemical immunosensor for testosterone using functionalized magnetic beads and screen-printed carbon electrodes
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
An electrochemical immunosensor for testosterone using functionalized magnetic beads and screen-printed carbon electrodes
چکیده انگلیسی

A disposable electrochemical immunosensor using screen-printed carbon electrodes (SPCEs) and protein A-functionalized magnetic beads (MBs) was developed for the determination of testosterone. Anti-testosterone was immobilized onto MBs and a direct competitive immunoassay involving testosterone labeled with peroxidase (HRP) was performed. The resulting conjugate was trapped on the SPCE with a small magnet. Testosterone determination was carried out by amperometry at −0.2 V upon H2O2 additions using hydroquinone (HQ) as the redox mediator. The experimental variables involved in the immunosensor response to testosterone were evaluated. Under the optimized conditions, a calibration plot for testosterone was obtained with a linear range between 5.0 × 10−3 and 50 ng/mL (r = 0.995). The detection limit was 1.7 pg/mL and the EC50 was 0.25 ± 0.04 ng/mL. These characteristics are notably better than those achieved with other reported immunosensors. Furthermore, anti-testosterone/MBs conjugates were shown to be stable for at least 25 days. A good selectivity was also found against other steroid hormones. The usefulness of the immunosensor was demonstrated by analyzing human serum spiked with 1 and 10 ng/mL testosterone.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biosensors and Bioelectronics - Volume 26, Issue 2, 15 October 2010, Pages 517–522
نویسندگان
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