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The use of microfluidic fuel cells (μFCs) as power sources in the development of non-implantable biomedical devices, such as patch sensors, could be broadened with the use of physiological fluids as fuels and the use of low-cost materials. In this work, we report the evaluation of a paper-based photo-μFC working with human blood as fuel, and we implement a nanocomposite as anode that presents photoactivity under visible light. The electrocatalyst was synthesized using Zn(NO3)2 and TiCl4 as precursors of the ZnO and the TiO2, respectively, which were coated with Au nanoparticles. It was demonstrated that ZnO and TiO2 nanoparticles consisted of crystals with wurtzite and anatase phases, with average sizes of 26.6 and 19.5 nm, respectively, and the TiO2/ZnO/Au nanocomposite presents 2.62 eV of band gap energy, demonstrating its photoactivity under visible light irradiation. The photocatalyst was tested as photoanode in half-cell for glucose oxidation in aqueous solutions, under illumination and dark conditions, showing characteristics peaks of glucose oxidation in both cases, but higher current was generated under illumination. Finally, we present the implementation of this anode and the construction of a paper-based photo-μFC using human blood as fuel; its performance was evaluated under visible light irradiations and in the dark. The results show a better performance under illumination with voltage, current, and power density values of 0.95 V, 1.2 mA cm−2, and 0.458 mW/cm2, respectively, compared to the corresponding values of 0.8 V, 0.96 mA cm−2, and 0.274 mW/cm2 in dark conditions. [ABSTRACT FROM AUTHOR]