The ink composition was specifically optimized regarding the ratio of the major carbon-based components adenine-CNFA (N-source) and glucose-CNFA (foaming agent) (Figure and SI, p. S4, Figure ). As both, high concentrations of active N-sites and a good access to those sites by sufficient porosity are required, LP-NC films with a significant fraction of glucose-CNFA yield the highest responses. For the optimized sensor, comprehensively investigated in this study, a CNFA ratio of 90:10 wt% (adenine-CNFA:glucose-CNFA) was used.