چكيده به لاتين
In recent years, biosensors have attracted a lot of attention to diagnosing various diseases, especially cancers. In design of biosensors, bio receptors are used to detect pathogens factors, such as antibodies, DNA, RNA, aptamer, and etc. Due to the role of these cases in increasing the expression of pathogens factors associated with different types of cancer and also their presence in different parts of the body, especially body liquids such as blood, serum, sweat, urine and saliva, these molecules have become biomarkers. They have become reliable for diagnosing different types of diseases.
The human papillomavirus (HPV) is related to near one hundred percent of cervical cancer. more than 200 types of this virus have introduced but the most common dangerous are the HPV-16 and 18 which are classified as the hrHPV (high-risk human papillomavirus). This two HPV types (16 and 18) cause 70percent of cervical cancers and pre-cancerous cervical lesions. In this study, an electrochemical biosensor was designed to measure HPV-16 as a marker of type 16 infection and to screen for cervical cancer. To prepare the biosensor the inexpensive graphite sheets (GS) was used. These plates were modified by single-walled carbon nanotubes, silver-dendrite nanostructures, and polypyrrole polymer nanoparticles. Then, a self-assembled monolayer (SAM) method was used to insert a HPV-16 capture probe and detect the HPV-16 target sequence and increase the selectivity of the electrode response. The electrode was examined and characterized by electron scanning microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy and X-ray energy dispersive (EDX) techniques. Then, the biosensor was used to measure the target molecule by differential pulse voltammetry technique in phosphate buffer salt solution (pH = 7.4) in the presence of Fe(CN)63-/4 redox prob. The proposed biosensor has a very wide linear range from 10-6 to 10 -18 M with a detection limit of 10-18 M.
