Label-free detection of DNA using high-κ Lu2Ti2O7 electrolyte-insulator-semiconductors
Label-free detection of DNA using high-κ Lu2Ti2O7 electrolyte-insulator-semiconductors
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DOI：
10.1039/c1jm14274g
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发表时间：
2012
影响因子：
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通讯作者：
T. Pan;Kung-Yuan Chang;Chao-Wen Lin;S. Tsai;Min-Hsien Wu
中科院分区：
文献类型：
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作者：
T. Pan;Kung-Yuan Chang;Chao-Wen Lin;S. Tsai;Min-Hsien Wu
在这项研究中，我们提出了一种一次性聚-N-异丙基丙烯酰胺（PNIPAAm）作为固定的生物材料为基础的电解质-绝缘体-半导体（EIS）的DNA检测装置，从高κ Lu 2 Ti 2 O 7传感膜制备。X射线衍射，X射线光电子能谱，原子力显微镜被用来研究这些薄膜在不同的退火温度下退火的结构和形态特征。在900 °C下退火的高κ Lu 2 Ti 2 O 7 EIS器件比在其他退火温度下退火的器件具有更高的灵敏度（60.04 mV/pH）、更小的滞后电压（3 mV）和更低的漂移速率（0.623 mV h−1）。这些结果归因于大的表面粗糙度和少量的晶体缺陷。在生物传感实验中，带负电荷的单链DNA探针（ssDNA）的Lu 2 Ti 2 O 7表面上的固定引起的参考电压值的增加，而互补的目标DNA（cDNA）的杂交降低了参考电压值。利用固定化ssDNA的PNIPAAm凝胶制备的Lu_2Ti_2O_7电化学阻抗传感器成功地用于DNA杂交的检测。互补DNA的检测限低至10 pM，并且Lu 2 Ti 2 O 7生物传感器的输出信号在10 - 11至10 - 4 M的范围内随cDNA浓度的对数线性增加。
In this study, we propose a disposable poly-N-isopropylacrylamide (PNIPAAm) as an immobilizing biological material based electrolyte-insulator-semiconductor (EIS) device for DNA detection, prepared from a high-κ Lu2Ti2O7 sensing membrane. X-ray diffraction, X-ray photoelectron spectroscopy, and atomic force microscopy were used to investigate the structural and morphological features of these films annealed at various annealing temperatures. The high-κ Lu2Ti2O7 EIS device annealed at 900 °C exhibited a higher sensitivity of 60.04 mV/pH, a smaller hysteresis voltage of 3 mV, and a lower drift rate of 0.623 mV h−1 than those at other annealing temperatures. These results are attributed to the large surface roughness and the small number of crystal defects. In the biosensing experiments, the immobilization of a negatively charged single-stranded DNA probe (ssDNA) on the Lu2Ti2O7 surface caused an increase in the reference voltage value, whereas the hybridization of complementary target DNA (cDNA) decreased the reference voltage value. The Lu2Ti2O7 EIS biosensor using a ssDNA-immobilized PNIPAAm gel was successfully used for the detection of DNA hybridization. The detection limit of complementary DNA was as low as 10 pM, and the output signal of the Lu2Ti2O7 biosensor increased linearly with the logarithm of cDNA concentration in the range of 10−11 to 10−4 M.