there are increasing concerns about the danger that water-borne pathogens and pollutants pose to the public. of particular importance are those that disrupt the plasma membrane, since loss of membrane integrity can lead to cell death. currently, quantitative assays to detect membrane-disrupting (lytic) agents are done offsite, leading to long turnaround times and high costs, while existing colorimetric point-of-need solutions often sacrifice sensitivity. Thus, portable and highly sensitive solutions are needed to detect lytic agents for health and environmental monitoring. Here, a lipid-based electrochemical sensing platform is introduced to rapidly detect membrane-disrupting agents. the platform combines benchtop fabricated microstructured electrodes (MSes) with lipid membranes. the sensing mechanism of the lipid-based platform relies on stacked lipid membranes serving as passivating layers that when disrupted generate electrochemical signals proportional to the membrane damage. the MSe topography, membrane casting and annealing conditions were optimized to yield the most reproducible and sensitive devices. We used the sensors to detect membrane-disrupting agents sodium dodecyl sulfate and Polymyxin-B within minutes and with limits of detection in the ppm regime. This study introduces a platform with potential for the integration of complex membranes on MSEs towards the goal of developing Membrane-on-chip sensing devices.Bacterial pathogens, pesticides, and parasitic vectors are common water-borne risks that are currently detected and quantified using methods such as ELISA, chromatography, and mass spectrometry. These methods are reliable and offer high precision and accuracy, but are expensive, require highly trained technicians, and are time consuming 1-3 , which precludes their use in resource-limited environments 3-6 . Thus, there is an increasing demand for diagnostic tools that do not compromise affordability, sensitivity, and portability for applications in point-of-care (PoC) diagnostics 3,7 , personalized medicine 8,9 , food quality assessment 10,11 , and water testing 12 . Biosensors are attractive routes to address these needs because they leverage biorecognition elements to offer rapid and low-cost solutions for the detection of potentially harmful agents and can be adapted to portable platforms [13][14][15][16] . Particularly relevant to food safety, environmental testing and biosecurity areas is the development of biosensors that can detect the disruption of the cell plasma membrane -a hallmark of the presence of pathogenic microorganisms or toxins that can pose serious threats to human health.The cell plasma membrane is a complex structure that separates the internal cellular components from external environments. Apart from protecting the cell from its surroundings, the plasma membrane mediates ion and small molecule transport, adhesion, motility, and the uptake of larger foreign bodies through endocytosis. The membrane is primarily composed of a phospholipid bilayer, within which sterols, carboh...
