A novel breathable electrochemical enzyme-free sensor made from laser-induced carbon nanofibers embedding Ni nanocatalysts (Ni-LCNFs) is proposed for the capture and detection of biomarkers in breath aerosol. The permeable Ni-LCNF electrodes were fabricated on filter paper where a hydrophobic wax barrier was created to confine the device's working area. The device was tested with aerosolized glucose, which was collected on the porous Ni-LCNF electrode. After a subsequent drying step, 0.1 M NaOH was dropped onto the device, and the electrocatalytic reaction of the captured glucose enabled by a Ni nanocatalyst was monitored via cyclic voltammetry (CV). Taking the oxidation/reduction peak ratios from CV as analytical signals improves the reliability and reproducibility of the glucose measurement. In the measurement step, closing the sensing area with adhesive tape, named