Tosar Juan Pablo, Keel Karen, Laíz Justo
Nuclear Research Center, Faculty of Science, Universidad de la República, Montevideo, Uruguay.
Biosens Bioelectron. 2009 Jun 15;24(10):3036-42. doi: 10.1016/j.bios.2009.03.016. Epub 2009 Mar 24.
Two direct reagent-free detection methods were tested with Au/polypyrrole/oligonucleotide modified electrodes. Detection by monitoring guanine oxidation was realized amperometrically using an experimental setup which does not require any expensive electrochemical equipment and is therefore suitable for in situ detection. Target detection was also realized by monitoring the decrease in the amplitude of polypyrrole oxidation and reduction peaks in cyclic voltammetry experiments after incubation or injection of target into the electrochemical cell. Detection of 53 pM target within a 2000x excess of non-complementary sequences was possible. The possibility of a dual detection scheme in the same biosensor, with both detection schemes being totally independent from one another is very promising for genosensor design since it would result in a significant decrease in the number of false positive and false negative samples.
采用金/聚吡咯/寡核苷酸修饰电极测试了两种直接无试剂检测方法。通过监测鸟嘌呤氧化实现检测，采用的实验装置为安培法，该装置不需要任何昂贵的电化学设备，因此适用于原位检测。在将靶标孵育或注入电化学池后，通过监测循环伏安实验中聚吡咯氧化峰和还原峰幅度的降低，也实现了靶标的检测。在存在2000倍过量非互补序列的情况下，能够检测到53 pM的靶标。在同一生物传感器中采用两种完全相互独立的检测方案进行双重检测，这种可能性对于基因传感器设计非常有前景，因为这将显著减少假阳性和假阴性样本的数量。
