This work reports on Ti1-xAgx and Ag-TiNx electrodes deposited by dc/pulsed dc magnetron sputtering at room temperature on poly (vinylidene fluoride) (PVDF) with the purpose to develop sensors for prosthesis. In Ti1-xAgx electrodes, silver content was varied from 0 to 100 at.%; and for Ag-TiNx electrodes, the nitrogen content was varied between 34 to 43 at.% and the Ti/Ag ratio changed from 12.2 to 5.2. The antibacterial activity of the samples was assessed by agar diffusion method. Interestingly, samples from the Ag-TiNx series presented antibacterial activity, in contrast to the samples from Ti1-xAgx series. XPS results showed that the as-deposited samples from the Ag-TiNx series exhibited silver clusters smaller than 4 nm. In order to deepen the results obtained, samples were analysed after the Halo test (antibacterial test), and XPS analyses showed the disappearance of these Ag clusters in agreement with the SEM results, which displayed a visible aggregation and a significant decrease in the number of Ag clusters, suggesting that silver nanoparticles aggregated and diffused through the agar killing bacteria or inhibiting their grown in the vicinity. All results show that Ag-TiNx electrodes are more promising candidates to be used in PVDF sensor protection than Ti1-xAgx electrodesS. M. Marques gratefully acknowledges the funding from the Portuguese National funds through the FCT - Fundacao para a Ciencia e a Tecnologia, (project SFRH/BD/71259/2010). Also, the authors thank the support of FEDER through the COMPETE Programme and of the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project PEST-C/FIS/UI607/2014 and the project Matepro-Optimizing Materials and Processes, ref. NORTE-07-0124-FEDER-000037", co-funded by the "Programa Operacional Regional do Norte" (ON.2 - O Novo Norte), under the "Quadro de Referencia Estrategico Nacional" (QREN), through the "Fundo Europeu de Desenvolvimento Regional" (FEDER).The authors thank the FCT Strategic Project of UID/BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the project "BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes", REF. NORTE-07-0124-FEDER-000028 co-funded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, FEDER.The authors thank the FCT Strategic Project of UID/BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the Project "BioHealth Biotechnology and Bioengineering approaches to improve health quality", Ref. NORTE-07-0124-FEDER-000027, co-funded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, FEDER.The authors thank the FCT Strategic Project of UID/BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and the Project "BioEnv Biotechnology and Bioengineering for a sustainable world", REF. NORTE-07-0124-FEDER-000048, co-funded by the Programa Operacional Regional do Norte (ON.2 0 Novo Norte), QREN, FEDER