Electrochemical biosensors are promising for sensing in low-resource settings because they are easy use and low-cost. Disposable screen-printed electrodes are popular for biosensing applications, but the dopants in the ink used for gold electrode production can interfere with electrode modification and sensing. We have developed an alternative disposable electrode made from high-quality gold leaf. We compared the topology and performance of three different disposable gold electrodes: our gold leaf electrodes and two commercial screen-printed versions. Our electrodes consistently outperformed commercial electrodes for biosensing, and we have further expanded these electrodes for the detection of infectious disease. In contrast, carbon screen-printed electrodes tend to be lower cost and higher quality than their gold counterparts. However, chemistry to modify them with biomolecules remains more challenging than self-assembly on gold. We have therefore developed new chemistries to enable the facile modification of these electrodes with biomolecules and have successfully applied these modified electrodes for environmental sensing. Together, these works demonstrate the importance of fundamental advances in platform design to enable improved technologies.