چكيده فارسي :
Sensitive, selective, inexpensive and simple-to-use human immunodeficiency virus (HIV) diagnostics are urgently needed for early diagnosis and monitoring of the HIV [1]. To address this issue, in our work, we developed a novel label free liquid-ion gated field effect transistor (FET)-type biosensor for HIV gene detection with the development of p-type semiconducting nickel oxide (NiO) thin film using reproducible radio frequency (RF) magnetic sputtering technique. Initially, to optimize the thickness, NiO nanoscale films with different thicknesses have been prepared via RF magnetic sputtering on the glass susbstrates. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images and energy dispersive X-ray spectroscopy (EDX) analysis of these thin films were recorded and the best thickness with the highest current was selected for immobilization of the HIV-1 5’-amino-modified probe single strand DNA (ssDNA). The ssDNA was then immobilized covalently on the surface of the NiO thin film modified with (3-Aminopropyl)triethoxysilane. By integration of the advantages of the NiO and liquid-ion gated FET, an innovative and efficient DNA HIV biosensor (NiO-FET) has been achieved for detection of target HIV DNA specifically and sensitively in a linear range from 1.0 aM to 10.0 nM with a detection limit of 0.5 aM. At the same time, the approach was exhibited good selectivity even against non-complementary and two bases mismatched sequences. The proposed biosensor was also successfully applied to detect HIV DNA in human serum samples. The obtained satisfactory results show high performance label free FET-type biosensor to detect HIV DNA and this device has a promising potential application to monitor other DNA biomarkers in biological fluids and clinical samples.
