Intestinal organoids: A new paradigm for engineering intestinal epithelium in vitro.

In recent years, the advent of intestinal organoid culture systems has revolutionized in vitro studies of the small intestine epithelium. Intestinal organoids are derived from self-organizing and self-renewing intestinal stem cells and closely recapitulate the native intestinal epithelium. They therefore represent a more physiologically-relevant in vitro model than conventional cell cultures for studying intestinal development, biology and pathophysiology. Moreover, they represent a promising and unprecedented new tool in the realm of regenerative and personalized medicine. In this review, we outline the current approaches to develop intestinal organoids and describe the strategies used to induce complexity, multicellularity and modularity in organoid culture systems; this knowledge will contribute to improved biomimicry of the organoid culture system. We focus on co-culture systems and explore the convergence of organoid technology and engineering principals. Finally, we describe applications of intestinal organoids in various fields.

Intelligent Food Packaging: A Review of Smart Sensing Technologies for Monitoring Food Quality.

Food safety is a major factor affecting public health and the well-being of society. A possible solution to control food-borne illnesses is through real-time monitoring of the food quality throughout the food supply chain. The development of emerging technologies, such as active and intelligent packaging, has been greatly accelerated in recent years, with a focus on informing consumers about food quality. Advances in the fields of sensors and biosensors has enabled the development of new materials, devices, and multifunctional sensing systems to monitor the quality of food. In this Review, we place the focus on an in-depth summary of the recent technological advances that hold the potential for being incorporated into food packaging to ensure food quality, safety, or monitoring of spoilage. These advanced sensing systems usually target monitoring gas production, humidity, temperature, and microorganisms' growth within packaged food. The implementation of portable and simple-to-use hand-held devices is also discussed in this Review. We highlight the mechanical and optical properties of current materials and systems, along with various limitations associated with each device. The technologies discussed here hold great potential for applications in food packaging and bring us one step closer to enable real-time monitoring of food throughout the supply chain.

Sentinel Wraps: Real-Time Monitoring of Food Contamination by Printing DNAzyme Probes on Food Packaging.

Here, we report the development of a transparent, durable, and flexible sensing surface that generates a fluorescence signal in the presence of a specific target bacterium. This material can be used in packaging, and it is capable of monitoring microbial contamination in various types of food products in real time without having to remove the sample or the sensor from the package. The sensor was fabricated by covalently attaching picoliter-sized microarrays of an E. coli-specific RNA-cleaving fluorogenic DNAzyme probe (RFD-EC1) to a thin, flexible, and transparent cyclo-olefin polymer (COP) film. Our experimental results demonstrate that the developed (RFD-EC1)-COP surface is specific, stable for at least 14 days under various pH conditions (pH 3-9), and can detect E. coli in meat and apple juice at concentrations as low as 103 CFU/mL. Furthermore, we demonstrate that our sensor is capable of detecting bacteria while still attached to the food package, which eliminates the need to manipulate the sample. The developed biosensors are stable for at least the shelf life of perishable packaged food products and provide a packaging solution for real-time monitoring of pathogens. These sensors hold the potential to make a significant contribution to the ongoing efforts to mitigate the negative public-health-related impacts of food-borne illnesses.