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Logic gates are an indispensable part of digital circuits, and therefore such devices with fast operating speeds and simple designs are vital for all kinds of electronic applications. This paper proposes simple Y‐shaped designs of all‐optical AND, OR, and NOT logic gates in two dimensions that are operational in both TE and TM modes. These gates are designed using silicon slab waveguides, which makes them relatively easy to fabricate. The logic gates are designed, analyzed, and optimized at 1.55 µm using the finite difference time domain method. The truth tables of the proposed all‐optical logic gates are realized for every input case. The propagation delay time is determined to be of the order of femtoseconds (10−15 s), which is very fast compared to the response time of the currently reported all‐optical logic gates (10−9 ‐ 10−12 s). [ABSTRACT FROM AUTHOR]

Background: Reactive oxygen species (ROS) are powerful weapons for various anticancer therapies. However, high glutathione (GSH) levels in cancer cells can significantly reduce the efficacy of such therapies. Methods: In this study, pH-responsive fluorescein-encapsulated zeolitic imidazolate framework-8 nanoparticles were synthesized for ROS-mediated combination therapy. Results: Upon blue light activation, fluorescein displayed a high singlet oxygen photogeneration ability for photodynamic therapy. Concurrently, accumulated Zn2+ from degraded zeolitic imidazolate framework-8 stimulated simultaneous ROS generation and GSH depletion, thereby successfully inducing chemodynamic therapy. This triggered a cascade of photo–physical and chemical processes culminating in the localized generation of ROS, ultimately breaking the intracellular redox equilibrium. Conclusion: This nanoformulation can potentially be used for light-activated ROS-mediated therapy for the management of superficial tumors. Highly reactive molecules called reactive oxygen species (ROS) are known to be present in excess in cancer cells. As a result, cancer cells are more susceptible to death by any further rise in levels of these species. In the current study, fluorescein-encapsulated zeolitic imidazolate nanoparticles were prepared for blue light-activated ROS-enhancing combination therapy. The nanoparticles displayed significant toxicity against a breast cancer cell line and simultaneously induced glutathione depletion, an antioxidant known to reduce the efficacy of various cancer therapies. Thus, this study reveals the potential of fluorescein-encapsulated zeolitic imidazolate nanoparticles for light-activated ROS-mediated therapy for the treatment of superficial tumors. [ABSTRACT FROM AUTHOR]

The use of magnetic nanoparticles has greatly expanded for numerous biomedical applications over the past two decades due to their high surface area, size-dependent superparamagnetic properties, precision tunability, and easy surface modification. Magnetic nanoparticles can be engineered and manipulated with other nanoparticles and functional compounds to form multi-modal systems useful in theragnosis. However, superior biocompatibility, high loading efficacy, regulated drug release, and in vitro and in vivo stability are necessary for the efficient incorporation of these nanoparticles into physiological systems. In recent years, considerable advancements have been made and reported both in synthesis and application, given the broad range of biomedical-related prospective uses of magnetic nanoparticles. Here, in this review, we have highlighted some essential works, specifically related to the application of magnetic nanoparticles in drug delivery, magnetic hyperthermia, magnetic resonance imaging, magnetic particle imaging, biosensors, and tissue engineering. [ABSTRACT FROM AUTHOR]