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The development of high performing and stable energetic materials (EMs) is a focus for a variety of applications including explosives, propellants, and pyrotechnics. To enhance stability, energetic crystals are often interfaced with materials such as chemical binders, which can introduce a variety of physiochemical phenomena ultimately leading to unpredictable stability and performance within the composite. Therefore, a thorough understanding of how energetic crystals behave when interfaced with various chemical functionalities is crucial for designing safer, high performing energetic formulations. This work provides a fundamental insight into interactions between a high performing energetic material, CL-20 (hexanitrohexaazaisowurtzitane), and other materials' surfaces. Highly controlled, tunable 2D metal-halide perovskite (2D MHP) templates with tunable periodicity and chemistry were created and used as a template layer to influence nucleation and growth of CL-20 crystals. All MHP/CL-20 bilayer films exhibit small, nonuniform crystalline deposit morphology for the CL-20 crystals with β-CL-20 polymorphic structure. While most MHP films template the formation of β-CL-20 crystals with a (111) preferential orientation, PbPMA2Cl4/β-CL-20 films crystallize with a (020) preferential orientation. The results presented herein suggest interfacial energy minimization between the two bilayer components is the dominant driving force behind the CL-20 preferential orientations. This methodology can potentially be used for developing techniques for growing energetic crystals with desired morphology, packing density and crystallographic orientation. 

Aneuploidy, or an incorrect chromosome number, is ubiquitous among cancers. Whole-genome duplication, resulting in tetraploidy, often occurs during the evolution of aneuploid tumors. Cancers that evolve through a tetraploid intermediate tend to be highly aneuploid and are associated with poor patient prognosis. The identification and enrichment of tetraploid cells from mixed populations is necessary to understand the role these cells play in cancer progression. Dielectrophoresis (DEP), a label-free electrokinetic technique, can distinguish cells based on their intracellular properties when stimulated above 10 MHz, but DEP has not been shown to distinguish tetraploid and/or aneuploid cancer cells from mixed tumor cell populations. Here, we used high-frequency DEP to distinguish cell subpopulations that differ in ploidy and nuclear size under flow conditions. We used impedance analysis to quantify the level of voltage decay at high frequencies and its impact on the DEP force acting on the cell. High-frequency DEP distinguished diploid cells from tetraploid clones due to their size and intracellular composition at frequencies above 40 MHz. Our findings demonstrate that high-frequency DEP can be a useful tool for identifying and distinguishing subpopulations with nuclear differences to determine their roles in disease progression. 

Abstract The use of engineered cells, tissues, and organs has the opportunity to change the way injuries and diseases are treated. Commercialization of these groundbreaking technologies has been limited in part by the complex and costly nature of their manufacture. Process-related variability and even small changes in the manufacturing process of a living product will impact its quality. Without real-time integrated detection, the magnitude and mechanism of that impact are largely unknown. Real-time and non-destructive sensor technologies are key for in-process insight and ensuring a consistent product throughout commercial scale-up and/or scale-out. The application of a measurement technology into a manufacturing process requires cell and tissue developers to understand the best way to apply a sensor to their process, and for sensor manufacturers to understand the design requirements and end-user needs. Furthermore, sensors to monitor component cells’ health and phenotype need to be compatible with novel integrated and automated manufacturing equipment. This review summarizes commercially relevant sensor technologies that can detect meaningful quality attributes during the manufacturing of regenerative medicine products, the gaps within each technology, and sensor considerations for manufacturing.