Mohammad Reza Mohammad Shafiee; Janan Parhizkar
Abstract
Objective: The annual incidence of cancer in the world is growing rapidly. The most important factor in the cure of cancers is their early diagnosis. miRNA, as a biomarker for early detection of cancer, has attracted a lot of attention. Methods: In this study, an electrochemical biosensor was developed ...
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Objective: The annual incidence of cancer in the world is growing rapidly. The most important factor in the cure of cancers is their early diagnosis. miRNA, as a biomarker for early detection of cancer, has attracted a lot of attention. Methods: In this study, an electrochemical biosensor was developed to detect the amount of miR-106a, the biomarker of gastric cancer, by modifying a glassy carbon electrode (GCE) with a composite of graphitic carbon nitride and gold nanoparticles. Complementary DNA strand of miR-106a which modified with biotin was used as a probe. Nanoparticles of titanium phosphate modified with Streptavidin and zinc ions were used to generate the electrochemical signal in square wave voltammetry. To characterize the g-C3N4 functional group, the chemical composition of the titanium phosphate nanoparticles, the morphology and elemental composition of composite Fourier transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), and Energy Dispersive X-Ray Spectroscopy (EDS) were used, respectively. Results: The peaks of C, N, and Au in EDS spectrum confirmed composite formation. The linear range and detection limit of the modified biosensor for miRNA-106a were obtained from 0.6 to 6.4 nM and 80 pM, respectively. Conclusion: Ultimately, Au nanoparticles/ g-C3N4 composite modified electrode can be a good platform for making electrochemical biosensor to diagnosis cancer in early stages.
Mohadeseh Afzali; Mohammad Reza Mohammad Shafiee; Janan Parhizkar
Abstract
Objective: With the increasing incidence of cancer and the dramatic effect of early detection on treatment and increase patient's life, many efforts have been devoted to making sensitive diagnosis systems. DNA as a biomarker for diagnosis of different types of cancers at the early stages of illness has ...
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Objective: With the increasing incidence of cancer and the dramatic effect of early detection on treatment and increase patient's life, many efforts have been devoted to making sensitive diagnosis systems. DNA as a biomarker for diagnosis of different types of cancers at the early stages of illness has attracted much attention.Methods: In this research novel electrochemical biosensor was developed using Pb2+ modified titanium phosphate nanoparticles and two DNA as capture probes. Considerable amounts of lead ions were mounted on the surface of titanium phosphate which produced the electrochemical signal. The surface of the biosensor electrode was modified by Au nanorods/ g-C3N4 composite. The functional group on the surface of g-C3N4, the chemical composition of tip, the morphology of composite and elemental composition of the composite were investigated by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-Ray Spectroscopy (EDS), respectively.Results: The peaks of C, N, and Au were observed in the EDS spectrum. The presence of Au peaks in the EDS spectrum confirmed the formation of composite from Au nanorods and g-C3N4 sheets. Whit this biosensor the linear range from 0.6 nM to 6.4 nM and the detection limit of 20 PM for target DNA was obtained.Conclusion: Finally, it seems that the glassy carbon electrode modified with Au-nanorods/g-C3N4 composite is a good candidate for cancer diagnosis in the early stages.