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 work we studied the structural and optical properties of lithium tantalate ͑LiTaO 3 ͒ powders doped with Eu 3+ ions. We have examined the different sites occupied by the rare earth ion through the correlation of the DRX data analyzed with the Rietveld method and some spectroscopic parameters derived from the Eu 3+ luminescence. A direct relation was established between the lattice parameters and the "occupation fraction" of Eu 3+ in each LiTaO 3 site. The occupation fraction was set as the relative population of Eu 3+ ions for each site obtained by means of the intensity, baricenter, and the spontaneous emission coefficients of the 5 D 0 → 7 F 0 transitions. We concluded that the unit cell parameter a presents the same behavior of the Eu 3+ occupation fraction in Ta 5+ sites as a function of the Eu 3+ content in LiTaO 3 . The same was observed for the variation in Eu 3+ occupation fraction in the Li + site and the unit cell parameter c with the Eu 3+ content.

Mononuclear organic–inorganic hybrid lanthanoid complexes show that the combination of both types of ligands improves the optical response compared to the inorganic analogue, thus having potential optical applications due to their thermal response.