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Current additive manufacturing (AM) techniques and methods, such as liquid-crystal display (LCD) vat photopolymerization, offer a wide variety of surface-sensing solutions, but customizable internal sensing is both scarce in presence and narrow in scope. In this work, a fabrication process for novel customizable embedded ceramic temperature sensors is investigated. The fabrication techniques and materials are evaluated, followed by extensive characterization via spectral analysis and thermomechanical testing. The findings indicate that LCD-manufactured ceramic sensors exhibit promising sensing properties, including strong linear thermal sensitivity of 0.23% per °C, with an R2 of at least 0.97, and mechanical strength, with a hardness of 570 HV, making them suitable for adverse environmental conditions. This research not only advances the field of AM for sensor development but also highlights the potential of LCD technology in rapidly producing reliable and efficient ceramic temperature sensors. 

In eukaryotic organisms, protein kinases regulate diverse protein activities and signaling pathways through phosphorylation of specific protein substrates. Isolating and characterizing kinase substrates is vital for defining downstream signaling pathways. The Kinase Client (KiC) assay is an in vitro synthetic peptide LC-MS/MS phosphorylation assay that has enabled identification of protein substrates (i.e., clients) for various protein kinases. For example, previous use of a 2,100-member (2k) peptide library identified substrates for the extracellular ATP receptor-like kinase, P2K1. Many P2K1 clients were confirmed by additional in vitro and in planta studies, including Integrin-Linked Kinase 4 (ILK4), for which we provide the evidence herein. In addition, we developed a new KiC peptide library containing 8,000 (8k) peptides based on phosphorylation sites primarily from Arabidopsis thaliana datasets. The 8k peptides are enriched for sites with conservation in other angiosperm plants, with the paired goals of representing functionally conserved sites and usefulness for screening kinases from diverse plants. Screening the 8k library with the active P2K1 kinase domain identified 177 phosphopeptides, including calcineurin B-like protein (CBL9) and G protein alpha subunit 1 (GPA1), which functions in cellular calcium signaling. We confirmed that P2K1 directly phosphorylates CBL9 and GPA1 through in vitro kinase assays. This expanded 8k KiC assay will be a useful tool for identifying novel substrates across diverse plant protein kinases, ultimately facilitating the exploration of previously undiscovered signaling pathways. 

Additive manufacturing (AM) technology has recently seen increased utilization due to its versatility in using functional materials, offering a new pathway for next-generation conformal electronics in the smart sensor field. However, the limited availability of polymer-based ultraviolet (UV)-curable materials with enhanced piezoelectric properties necessitates the development of a tailorable process suitable for 3D printing. This paper investigates the structural, thermal, rheological, mechanical, and piezoelectric properties of a newly developed sensor resin material. The polymer resin is based on polyvinylidene fluoride (PVDF) as a matrix, mixed with constituents enabling UV curability, and boron nitride nanotubes (BNNTs) are added to form a nanocomposite resin. The results demonstrate the successful micro-scale printability of the developed polymer and nanocomposite resins using a liquid crystal display (LCD)-based 3D printer. Additionally, incorporating BNNTs into the polymer matrix enhanced the piezoelectric properties, with an increase in the voltage response by up to 50.13%. This work provides new insights for the development of 3D printable flexible sensor devices and energy harvesting systems. 

The inflammation marker Interleukin 6 (IL-6) typically remains below 5 pg/mL in the serum of healthy individuals but can increase tenfold during inflammation in chronic conditions like COVID-19 and rheumatoid arthritis, as well as acute conditions like sepsis. This study is focused on the rapid detection of IL-6 to monitor both chronic and acute diseases. The novel sensor, designed with gold-coated micropyramids on the electrodes, was fabricated using the two-photon polymerization method, enabling low-volume sensing capabilities (2-3 μL). The micropyramids were surface functionalized with interleukin-6 antibodies towards developing an affinity biosensor specific to the physiological relevant range of IL-6 of 5.1 and 18.8 pg/mL in mild inflammation. Sensing was achieved by measuring impedance changes associated with IL-6 binding to the antibodies on the micropyramids interfaced using electrochemical impedance spectroscopy. It was observed that the signals from the lowest detection concentration was enhanced by 3 times at 1500 hz when the 532 nm green laser was incident on the micropyramids. This innovative approach can be expanded to the detection of cytokines not only in serum but also in respiratory samples. As a result, it opens up new avenues for monitoring local inflammation within the lungs and assessing systemic inflammation levels throughout the body.