TAU Nanocenter

Controlled release systems are often integrated into polymeric scaffolds to supply essential biofactors to trigger physiological processes in engineered tissues. Here, we report the modification of chondroitin sulfate (CS) electroactive polymer with gold nanorods (AuNRs) to create hybrid macroporous scaffolds for enhanced on-demand release of growth factors and cytokines. The mechanical properties, porosity and degradation of the hybrid scaffolds were evaluated, and the viability and functionality of seeded cardiac cells were assessed. Following, the ability to control the release of the enzyme lysozyme, and the cytokine, stromal cell-derived factor 1 (SDF-1) by applying electrical stimulation, was demonstrated. The AuNRs were able to increase the current through the scaffolds, providing an efficient on–off release profile of SDF-1, which resulted in higher migration of cells expressing CXCR4 receptor. Finally, the …

This comment on the paper by Karlovets and Pupasov-Maksimov [Phys. Rev. A 103, 012214 (2021)] addresses their criticism of the combined experimental and theoretical study by Remez et al.[Phys. Rev. Lett. 123, 060401 (2019)]. We show, by means of simple optical arguments as well as numerical simulations, that the arguments raised by Karlovets and Pupasov-Maksimov do not hold in the experimental regime reported by Remez et al. Further, we discuss a clarification for the theoretical derivations presented by Karlovets and Pupasov-Maksimov, as they hold only when the final state of the emitting electron is observed in coincidence with the emitted photon. Although this scenario is feasible and may stimulate new experimental regimes that do correspond to the predictions reported by Karlovets and Pupasov-Maksimov, it is not the common scenario in cathodoluminescence, where only the light is measured …

The growing in manufacturing and applications of graphene oxide (GO), a two-dimensional nanomaterial, highlights the need for a better understanding of its environmental impact and toxicity. This work investigates the interaction of GO with cell membrane models as an indication for GO's potential harmfulness. A wide range of biologically-relevant membrane parameters (size, charge and, cholesterol content) and simple optical techniques were used to evaluate the outcome of interactions of vesicular cell membrane models with GO. Loss of membrane integrity was found to be positively correlated with electrostatic attraction and negatively correlated with cholesterol content. The size of vesicle-GO aggregates increased as a function of initial vesicle size, while cholesterol content was found to have a negligible effect on aggregation. Interestingly, charged vesicles reduced vesicle-GO aggregate size either by …

We investigate bright and dark diffractive focusing emerging in the free propagation of specific wave profiles. These general wave phenomena manifest themselves in matter, water, and classical waves. In this article, we lay the foundations for these effects and illustrate their origin in Wigner phase space. Our theoretical studies are supported by experimental demonstrations of dark focusing in water waves. Moreover, by using different phase slits we analyze several aspects of bright and dark focusing for classical and matter waves.

The geometric phase of light has been demonstrated in various platforms of the linear optical regime, raising interest both for fundamental science as well as applications, such as flat optical elements. Recently, the concept of geometric phases has been extended to nonlinear optics, following advances in engineering both bulk nonlinear photonic crystals and nonlinear metasurfaces. These new technologies offer a great promise of applications for nonlinear manipulation of light. In this review, we cover the recent theoretical and experimental advances in the field of geometric phases accompanying nonlinear frequency conversion. We first consider the case of bulk nonlinear photonic crystals, in which the interaction between propagating waves is quasi-phase-matched, with an engineerable geometric phase accumulated by the light. Nonlinear photonic crystals can offer efficient and robust frequency conversion in …

Cell therapy using induced pluripotent stem cell‐derived neurons is considered a promising approach to regenerate the injured spinal cord (SC). However, the scar formed at the chronic phase is not a permissive microenvironment for cell or biomaterial engraftment or for tissue assembly. Engineering of a functional human neuronal network is now reported by mimicking the embryonic development of the SC in a 3D dynamic biomaterial‐based microenvironment. Throughout the in vitro cultivation stage, the system's components have a synergistic effect, providing appropriate cues for SC neurogenesis. While the initial biomaterial supported efficient cell differentiation in 3D, the cells remodeled it to provide an inductive microenvironment for the assembly of functional SC implants. The engineered tissues are characterized for morphology and function, and their therapeutic potential is investigated, revealing improved …

Intracellular recording of action potentials is an essential mean for studying disease mechanisms, and for electrophysiological studies, particularly in excitable cells as cardiomyocytes or neurons. Current strategies to obtain intracellular recordings include three-dimensional (3D) nanoelectrodes that can effectively penetrate the cell membrane and achieve high-quality intracellular recordings in a minimally invasive manner, or transient electroporation of the membrane that can yield temporary intracellular access. However, the former strategy requires a complicated and costly fabrication process, and the latter strategy suffers from high dependency on the method of application of electroporation, yielding inconsistent, suboptimal recordings. These factors hinder the high throughput use of these strategies in electrophysiological studies. In this work, we propose an advanced cell-based biosensing platform that relies on …

While molybdenum disulfide (MoS2) nanosheets have demonstrated selective and efficient adsorption potential toward heavy metals, there are still many barriers-such as nanomaterial practicality, safety, and sustainability-to nanomaterials' large-scale application in water treatment schemes. For example, nano-MoS2 has been shown to take part in redox reactions during heavy metal recovery (which deteriorates the active nanomaterial) and can release molybdenum to the treated water. This study addresses these barriers through the bottom-up hydrothermal synthetic growth of MoS2 onto granular activated carbon (AC) as an active adsorbing platform. Not only does this strategic design avoid redox reactions, but it also largely immobilizes MoS2 to a substrate, which mitigates nanomaterial loss to solution and enables facile recovery of the nanomaterial after use. The hybrid adsorbent (MoS2@AC) was extensively …

Biofouling is a multifaceted and unavoidable problem in the application of membrane separation technology. Here, we functionalized polyvinylidene fluoride (PVDF) ultrafiltration membranes with poly(ionic liquid) (PIL) brushes to provide them with antibiofouling properties. The PIL brush grafted membranes (PIL-M) were prepared via atom transfer radical polymerization (ATRP) using different ionic liquids (ILs) on the membrane surface. Four functionalized membranes with different alkyl chain lengths (C4-M, C8-M, C12-M, and C16-M) were prepared to explore the relationship between surface structure and antibacterial properties. Our results showed that all of the PIL-M had antibacterial capabilities with the highest efficiency of 84.6% for the C12-M. Moreover, the antibacterial performance was improved by increasing the ATRP reaction temperature and time. Liposome vesicles were used as the bacterial cell …

High levels of persistent contaminants such as microplastics (MPs) and trace organic compounds (TrOCs) in the aquatic environment have become a major threat on the ecosystem and human health. While MP's role as a vector of environmental TrOCs is widely discussed in the literature, the corresponding implications of the interaction between these two compounds on human health (i.e., their joint toxic effect) have not been illustrated. Using a TrOCs model (Triclosan, TCS) and primary MPs (polystyrene microbeads), this work evaluates the sorption and desorption potential of TCS and MPs in simulated environmental and cellular conditions, respectively, and estimates the single and joint toxicity of these interactions toward human cells (Caco-2). Surface functionality of the microbeads highly increased their adsorption capacity of TCS, from 2.3 mg TCS for non−functionalized microbeads to 4.6 mg and 6.1 mg TCS …

Simple Summary Triple-negative breast cancer (TNBC) is an aggressive disease that responds in a limited manner to immune checkpoint blockades targeting the PD-L1/PD-1 axis, suggesting that PD-L1 potentiates TNBC progression via pathways not related to immune suppression. We demonstrated that, in human breast cancer cells, PD-L1 expression increased in a cell-autonomous manner tumor cell growth, invasion and release of pro-metastatic factors; these activities were elevated by exposure to PD-1 and were markedly impaired in S283-mutated PD-L1-expressing cells. Invasion of WT-PD-L1-expressing TNBC cells depended on autocrine chemokine circuits, involving CXCR1/2, CCR2, CCR5 and their ligands. In T cell-deficient mice, WT-PD-L1 exhibited increased tumor growth and metastasis by TNBC cells, whereas S283A-PD-L1-expressing cells showed a very poor tumorigenic and metastatic profile. These findings on cell-autonomous and PD-1-induced pro-metastatic activities of PD-L1 in cancer cells suggest that treatments targeting PD-L1 could improve the efficacy of immune-targeting checkpoint inhibitors, e.g., anti-PD-1 or anti-CTLA-4 in TNBC. Abstract Therapies targeting the PD-L1/PD-1 axis have recently been introduced to triple-negative breast cancer (TNBC) with limited efficacy, suggesting that this axis promotes tumor progression through mechanisms other than immune suppression. Here, we over-expressed WT-PD-L1 in human TNBC cells (express endogenous PD-L1) and in luminal-A breast cancer cells (no endogenous PD-L1 expression) and demonstrated that cell-autonomous …

Spatial modes of light can be used as carriers of information in classical optical communication or as an alphabet in quantum optical communication. In order to exploit the spatial domain, it is required to (de)multiplex different modes from a shared input channel into different output ports. Mode sorters have been employed in free-space and fiber systems but to date have not been realized for planar guided waves. Here we present a general method for compact on-chip sorting of different planar beams with a micrometric footprint and nanometric thickness. The designs were generated using a linkage-tree-based genetic algorithm and were experimentally demonstrated on a surface plasmon polariton platform by sorting of Hermite–Gaussian beams. The method used here can be readily applied to optimize complex, large-scale optical devices involving beam propagation methods.

While molybdenum disulfide (MoS2) nanosheets have demonstrated selective and efficient adsorption potential toward heavy metals, there are still many barriers—such as nanomaterial practicality, safety, and sustainability—to nanomaterials’ large-scale application in water treatment schemes. For example, nano-MoS2 has been shown to take part in redox reactions during heavy metal recovery (which deteriorates the active nanomaterial) and can release molybdenum to the treated water. This study addresses these barriers through the bottom-up hydrothermal synthetic growth of MoS2 onto granular activated carbon (AC) as an active adsorbing platform. Not only does this strategic design avoid redox reactions, but it also largely immobilizes MoS2 to a substrate, which mitigates nanomaterial loss to solution and enables facile recovery of the nanomaterial after use. The hybrid adsorbent (MoS2@AC) was …

In this study, the extraordinary biosorption of mucin, a natural glycoprotein with selectivity towards metals in physiological processes, is leveraged to remove heavy metals from wastewater. The authors assess the performance of dissolved mucin for Hg2+ adsorption through studies of kinetics, capacity, and selectivity. The results show that mucin can adsorb more than 124 mg g−1 Hg2+ while exhibiting ultra‐fast kinetics, with an equilibrium reached in a few seconds. The adsorption levels are optimized in pHs higher than 4 and remain almost unchanged in the presence of background ions. X‐ray photoelectron spectroscopy and Fourier transform infrared analyses indicated that the sorption mechanism is dominated by electrostatic interactions and mercuric complexation with mucin's active sites, whereas the undesirable removal via mercuric reduction does not occur. To use mucin in a practical and green fashion for …

Mercury (Hg) contamination in groundwater has been recognized as a serious threat to human health and ecological systems all over the world. This study demonstrated that two-dimensional (2D) molybdenum disulfide (MoS2) nanosheets can efficiently remove Hg in groundwater, with high Hg uptake capacity, ultrafast removal kinetics, and excellent selectivity. Interestingly, we found that the groundwater matrix has profound implications on the Hg removal efficiency and mechanisms by MoS2 nanosheets. Specifically, surface adsorption is the dominant removal mechanism for Hg in DI water owing to the high affinity between Hg(II) and MoS2 via strong Lewis acid/base soft–soft interactions. In groundwater, however, the presence of Cl− renders HgClOH the dominant species, which can undergo adsorption onto MoS2 and homolytic cleavage to form the˙HgCl radical. As an intermediate radical, ˙HgCl could either …

In a myocardial infarction, blood supply to the left ventricle is abrogated due to blockage of one of the coronary arteries, leading to ischemia, which further triggers the generation of reactive oxygen species (ROS). These sequential processes eventually lead to the death of contractile cells and affect the integrity of blood vessels, resulting in the formation of scar tissue. A new heart therapy comprised of cardiac implants encapsulated within an injectable extracellular matrix‐gold nanoparticle composite hydrogel is reported. The particles on the collagenous fibers within the hydrogel promote fast transfer of electrical signal between cardiac cells, leading to the functional assembly of the cardiac implants. The composite hydrogel is shown to absorb reactive oxygen species in vitro and in vivo in mice ischemia reperfusion model. The reduction in ROS levels preserve cardiac tissue morphology and blood vessel integrity …

Potable reuse of municipal wastewater is often the lowest-energy option for increasing the availability of fresh water. However, limited data are available on the energy consumption of potable reuse facilities and schemes, and the many variables affecting energy consumption obscure the process of estimating energy requirements. By synthesizing available data and developing a simple model for the energy consumption of centralized potable reuse schemes, this study provides a framework for understanding when potable reuse is the lowest-energy option for augmenting water supply. The model is evaluated to determine a representative range for the specific electrical energy consumption of direct and indirect potable reuse schemes and compare potable reuse to other water supply augmentation options, such as seawater desalination. Finally, the model is used to identify the most promising avenues for further …

In situ chemical ozonation (ISCO3), in which gaseous ozone is being injected into the subsurface, is a common method for remediating contaminated groundwater that is largely affected by the inevitable consumption of ozone by soil itself (rather than the target contaminants). In this study, ozone consumption by two main soil types of Israeli coastline aquifer was examined. Iron-rich soil showed considerably higher reactivity than did calcareous soil. We further investigated the effect of both physical and chemical soil characteristics on finite and catalytic ozone decay, hydroxyl-radical formation, and ozone transport behavior. Ozone consumption increased by >90% in the presence of fine soil particles (<100 μm), resulting from the large number of reactive sites and the higher content of ozone consumers compared to coarse soil particles. Soil organic matter consumed ozone twice as fast as iron components, promoted …