In this research, ZnO nanorods - Au nanoparticles nanohybrids have been fabricated and employed to sensitive electrochemical strategy for the specific detection of the ovarian cancer antigen CA-125/MUC126. The microdevice was developed in our lab based on gold and silver electrodes sputtered on glass substrate. The ZnO nanorods arrays were grown on working electrode using assisted microwave hydrothermal synthesis than gold nanoparticles (Au NPs) were deposited by sputtering. The Au NPs onto ZnO nanorods surface provides a favorable platform for efficient loading of anti-CA-125 antibody via binding with cystamine and glutaraldehyde. The effective loading of the biological material (CA-125 antibody and antigen) on the matrix was observed by SEM images. The electrochemical immunosensor shows a sensitive response to ovarian cancer antigen recombinant human CA-125/MUC126 with detection of 2.5ng/μL, 100 times lower than immunoblot system. Due to high specificity, reproducibility and noteworthy stability, the developed sensor will provide a sensitive, selective and convenient approach to be used to detect CA-125/MUC126.

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In this report, hierarchical ZnO nano- and microstructures were directly grown for the first time on a bacterial cellulose substrate and on two additional different papers by hydrothermal synthesis without any surface modification layer. Compactness and smoothness of the substrates are two important parameters that allow the growth of oriented structures.

Isopropanol sensors on flexible PET substrates presented high-performance at room-temperature in terms of sensitivity, selectivity and mechanical stability.

a b s t r a c tGraphene-based composites have emerged as gas sensor due to the possibility to obtain higher surface area with additional functional groups. In this paper, ZnO nanorods (ZnO-NR) with controlled size and morphology were grown via chemical bath deposition in mild temperature (90 C) over gold interdigital tracks deposited on an alumina substrate. Furthermore, it was also possible to obtain by the same method composites with graphene oxide sheets below ZnO-NR structures (GO/ZnO-NR) or ZnO-NR between GO sheets (GO/ZnO-NR/GO) when GO is placed in the bath during the growth of GO/ZnO-NR. The samples were characterized by Raman spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. These structures were tested as sensors of volatile organic compounds (VOCs), such as acetone, benzene, ethanol and methanol in the concentration range of 10e500 parts per million (ppm). It was found that the optimum working temperature of all sensors was 450 C. The GO/ ZnO-NR/GO composite showed better selectivity due to GO functional groups. In the case of our welldesigned sensors, we found that the dominant oxygen species (O 2-) on ZnO-NR surface were responsible for the sensors response. These findings offer a new viewpoint for further advance of the sensing performance of one-dimensional ZnO/GO nanocomposites VOCs sensors.