Sandia Labs FY21 LDRD Annual Report

FY21 ANNUAL REPORT

Instantaneous 3D temperature measurements via ultrafast laser spectroscopy with structured light.

Optical measurements can provide accurate data in hostile environments where physical probes are not feasible but are typically performed at a point or along a line. This project combined various optical diagnostic techniques with principles of structured illumination to provide enhanced dimensionality. In this research, structured illumination involved the use of modulated intensity patterns, which were used to distinguish optical signals from different spatial locations and from background optical signals much as a lock-in amplifier filters signals in the time domain. This technology was demonstrated for multi-planar particulate concentration measurements in turbulent flames with a single laser and a single camera and was applied to distinguish laser-induced fluorescence signals from intense background radiation in detonation fireballs. Additionally, emission spectroscopy from multiple 1D measurement locations

was demonstrated with a single set of detection optics and camera. These measurement techniques will be transformative for future studies in heat transfer and fluid dynamics where multi- dimensional data will aid in understanding complex phenomena. (PI: Daniel Richardson)

Simultaneous measurements from six different planes are performed with a single camera using structured illumination and Fourier-domain filtering.

Impacting the nanotherapeutics community via zeolitic imidazolate frameworks. This LDRD project investigated the relevance of zeolitic imidazolate frameworks (ZIFs) as a materials platform responsive to intracellular pH in the biologically relevant range (5.2-7.4). Rationally designed nanomaterials responsive in this range contribute to emergent intracellular pathogen treatment. Endosomal trapping is one of the greatest barriers to the development of nanomaterial-based therapeutic delivery, since it leads to the destruction of the nanomaterial and cargo. Researchers first investigated how the structural features and chemical functionality in ZIFs are impacted by change in pH and how ZIFs respond to the intracellular environment. Based on their findings, they successfully synthesized a variety of size tunable ZIF nanoparticles with distinct topologies and chemical functionalities. To facilitate rapid and comparable assessment of endosomal release through endosomal pore formation or endosomal rupture, the team developed quantitative imaging strategies for endosomal interactions and assessed the importance of coatings to the cellular interactions of ZIFs with mammalian cells. This project generated relevant new capabilities in nanoscience through both nanomaterials and novel endosomal imagining modalities development. Further, it produced a generalizable and quantifiable method to understand endosomal interactions of nanomaterials, which will greatly impact the nanotherapeutics community. This research will enable novel technologies for the delivery of advanced therapeutics needed to counter biothreat agents. (PI: Dorina Gallis)

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LABORATORY DIRECTED RESEARCH & DEVELOPMENT