Biomolecular monitoring in the gastrointestinal tract could offer rapid, precise disease detection and management but is impeded by access to the remote and complex environment. Here, we present an ingestible micro-bio-electronic device (IMBED) for in situ biomolecular detection based on environmentally resilient biosensor bacteria and miniaturized luminescence readout electronics that wirelessly communicate with an external device. As a proof of concept, we engineer heme-sensitive probiotic biosensors and demonstrate accurate diagnosis of gastrointestinal bleeding in swine. Additionally, we integrate alternative biosensors to demonstrate modularity and extensibility of the detection platform. IMBEDs enable new opportunities for gastrointestinal biomarker discovery and could transform the management and diagnosis of gastrointestinal disease.

The recent steady improvements in the performance of the nascent hybrid perovskite photovoltaic (PV) devices have led to power conversion efficiencies that rival the best-performing established PV technologies. However, to scale these laboratory demonstrations to PV module-scale production will require development of scalable deposition methods for perovskite thin films. Every record result for perovskite PVs so far was achieved via spin coating, a technique that is popular in research laboratories for thin-film coating over relatively small device areas, but not considered to be a method that could be used to scale up the manufacturing of perovskite PVs. Significantly larger thin-film areas are needed for future commercial PV products. Hence, some researchers have focused their efforts on perovskite deposition techniques that can be considered as scalable for mass production and have achieved notable results even on large areas. Here, we present an overview of the solution-based and vapor-based deposition processes; we explain their influence on the molecular crystal growth behavior of perovskite thin films and discuss the morphology as well as other material quality characteristics. By presenting a comprehensive comparison of the deposition techniques and the corresponding performance parameters for different device sizes, we intent to guide the growing research community through the methods that might enable mass production of perovskite solar products.

The authors would like to thank the two anonymous reviewers for their insightful and constructive comments that improved the quality of our work as well as the Ministry of Economic Affairs and Climate Policy of the Netherlands for its financial support enabling the research behind this publication.

Low viscosity rapid drying perovskite formulations designed to give high quality solar films when slot-die coated on flexible roll-to-roll compatible substrates are developed .