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Oct 2022 • 2022 IEEE International Topical Meeting on Microwave Photonics (MWP), 1-4, 2022

Electro-Opto-Mechanical Microwave-Frequency Oscillator in a Surface Acoustic Wave Silicon-Photonic Circuit

Maayan Priel, Saawan Kumar Bag, Matan Slook, Leroy Dokhanian, Inbar Shafir, Etai Grunwald, Moshe Katzman, Mirit Hen, Avi Zadok

An electro-opto-mechanical microwave frequency oscillator is demonstrated through a silicon photonic circuit. An electrical signal modulates an optical pump wave input. Modulation is converted to a surface acoustic wave on the silicon circuit through absorption in a metallic grating and thermoelastic expansion. The acoustic wave is delayed and converted back to optics through photoelastic modulation of a continuous optical input probe wave in a racetrack resonator waveguide. The output probe is detected, and the obtained voltage is amplified and fed back to modulate the input optical pump wave. With sufficient feedback gain, the electro-opto-mechanical loop is driven to oscillations at 2.21 GHz frequency. The oscillator can be useful for integrated microwave photonics signal processing.

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Oct 2022 • ACS Energy Letters

Solvent-Assisted Hopping Mechanism Enables Ultrafast Charging of Lithium-Ion Batteries

Xiaoteng Huang, Ruhong Li, Chuangchao Sun, Haikuo Zhang, Shuoqing Zhang, Ling Lv, Yiqiang Huang, Liwu Fan, Lixin Chen, Malachi Noked, Xiulin Fan

Fast charging is regarded as one of the most coveted technologies for commercial Li-ion batteries (LIBs), but the lack of suitable electrolytes with sufficient ionic conductivity and effective passivation properties hinders its development. Herein, we designed a mixed-solvent electrolyte (1 M LiPF6 in fluoroethylene carbonate/acetonitrile, FEC/AN, 7/3 by vol.) to overcome these two limitations by achieving an FEC-dominated solvation structure and an AN-rich environment. The specific AN-assisted Li+ hopping transport behavior shortens the Li+ diffusion time, doubling the ionic conductivity to 12 mS cm–1, thus endowing the graphite anode with >300 mAh g–1 at 20C and reversible (de)intercalation over a wide temperature range (from −20 to +60 °C). Furthermore, the designed electrolyte triples the capacity of the 1 Ah graphite||LiNi0.8Mn0.1Co0.1O2 (NMC811) pouch cells at 8C in comparison with the commercial …

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Oct 2022 • Physical Review B

Mixed superconducting state without applied magnetic field

Alex Khanukov, Itay Mangel, Shai Wissberg, Amit Keren, Beena Kalisky

A superconducting (SC) mixed state occurs in type-II superconductors where the upper critical field H c 2 is higher than the thermodynamic critical field H c. When an applied field is in between these fields, the free energy depends weakly on the order parameter which therefore can be small (SC state) or zero (normal state) at different parts of the sample. In this paper we demonstrate how a normal state along a line traversing a superconductor can be turned on and off externally in zero field. The concept is based on a long, current-carrying excitation coil, piercing a ring-shaped superconductor. The ring experiences zero field, but the vector potential produced by the coil generates a circular current that destroys superconductivity along a radial line starting at preexisting nucleation points in the sample. Unlike the destruction of superconductivity with magnetic field, the vector potential method is reversible and …

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Oct 2022 • Proceedings of the National Academy of Sciences

Sequestration of gut pathobionts in intraluminal casts, a mechanism to avoid dysregulated T cell activation by pathobionts

Martina Sassone-Corsi, Shalhevet Azriel, Ariel Simon, Deepshika Ramanan, Adriana Ortiz-Lopez, Felicia Chen, Nissan Yissachar, Diane Mathis, Christophe Benoist

T cells that express the transcription factor RORγ, regulatory (Treg), or conventional (Th17) are strongly influenced by intestinal symbionts. In a genetic approach to identify mechanisms underlying this influence, we performed a screen for microbial genes implicated, in germfree mice monocolonized with Escherichia coli Nissle. The loss of capsule-synthesis genes impaired clonal expansion and differentiation of intestinal RORγ+ T cells. Mechanistic exploration revealed that the capsule-less mutants remained able to induce species-specific immunoglobulin A (IgA) and were highly IgA-coated. They could still trigger myeloid cells, and more effectively damaged epithelial cells in vitro. Unlike wild-type microbes, capsule-less mutants were mostly engulfed in intraluminal casts, large agglomerates composed of myeloid cells extravasated into the gut lumen. We speculate that sequestration in luminal casts of potentially …

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Oct 2022 • The Journal of Allergy and Clinical Immunology: In Practice

Lessons learned from five years of newborn screening for severe combined immunodeficiency in Israel

Atar Lev, Idan Sharir, Amos J Simon, Shiran Levy, Yu Nee Lee, Shirly Frizinsky, Suha Daas, Talia Saraf-Levy, Arnon Broides, Amit Nahum, Suhair Hanna, Polina Stepensky, Ori Toker, Ilan Dalal, Amos Etzioni, Jerry Stein, Etai Adam, Ayal Hendel, Nufar Marcus, Shlomo Almashanu, Raz Somech

BackgroundImplementation of newborn screening (NBS) programs for severe combined immunodeficiency (SCID) have advanced the diagnosis and management of affected infants and undoubtedly improved their outcomes. Reporting long-term follow-up of such programs is of great importance.ObjectiveWe report a 5-year summary of the NBS program for SCID in Israel.MethodsImmunologic and genetic assessments, clinical analyses, and outcome data from all infants who screened positive were evaluated and summarized.ResultsA total of 937,953 Guthrie cards were screened for SCID. A second Guthrie card was requested on 1,169 occasions (0.12%), which resulted in 142 referrals (0.015%) for further validation tests. Flow cytometry immune-phenotyping, T cell receptor excision circle measurement in peripheral blood, and expression of TCRVβ repertoire for the validation of positive cases revealed a …

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Oct 2022 • ACS nano

Optoelectronics of Atomic Metal–Semiconductor Interfaces in Tin-Intercalated MoS2

Avraham Twitto, Chen Stern, Michal Poplinger, Ilana Perelshtein, Sabyasachi Saha, Akash Jain, Kristie J Koski, Francis Leonard Deepak, Ashwin Ramasubramaniam, Doron Naveh

Metal–semiconductor interfaces are ubiquitous in modern electronics. These quantum-confined interfaces allow for the formation of atomically thin polarizable metals and feature rich optical and optoelectronic phenomena, including plasmon-induced hot-electron transfer from metal to semiconductors. Here, we report on the metal–semiconductor interface formed during the intercalation of zero-valent atomic layers of tin (Sn) between layers of MoS2, a van der Waals layered material. We demonstrate that Sn interaction leads to the emergence of gap states within the MoS2 band gap and to corresponding plasmonic features between 1 and 2 eV (0.6–1.2 μm). The observed stimulation of the photoconductivity, as well as the extension of the spectral response from the visible regime toward the mid-infrared suggests that hot-carrier generation and internal photoemission take place.

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Oct 2022 • ACS Applied Materials & Interfaces

Unique Mechanisms of Ion Storage in Polyaniline Electrodes for Pseudocapacitive Energy Storage Devices Unraveled by EQCM-D Analysis

Meital Turgeman, Gil Bergman, Amey Nimkar, Bar Gavriel, Elad Ballas, Fyodor Malchik, Mikhael D Levi, Daniel Sharon, Netanel Shpigel, Doron Aurbach

The optimal performance of organic electrodes for aqueous batteries requires their full compatibility with selected electrolyte solutions. Electrode materials having 1–3-dimensional structures of variable rigidity possess a confined space in their structure filled with water and electrolyte solutions. Depending on the rigidity and confined space geometry, insertion and extraction of ions into electrode structures are often coupled with incorporation/withdrawal of water molecules. Aside from the scientific interest in understanding the charging mechanism of such systems, co-insertion of solvent molecules affects strongly the charge storage capability of the electrodes for energy storage devices. We present herein in situ electrochemical quartz crystal microbalance with dissipation monitoring (EQCM-D) investigations of polyaniline (PANI) electrodes operating in various aqueous Na+-containing electrolytes, namely, Na2SO4 …

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Oct 2022 • Forward Brillouin Scattering in Standard Optical Fibers: Single-Mode …, 2022

Photoelastic Perturbations to the Dielectric Tensor Due to Guided Acoustic Modes

Avi Zadok, Hilel Hagai Diamandi, Yosef London, Gil Bashan

The photoelastic perturbations to the dielectric tensor in standard single-mode fibers, due to the oscillations of guided acoustic modes, are studied and formulated. Material displacement of acoustic modes is associated with local strain in every point within the fiber cross section. Strain, in turn, gives rise to dielectric perturbations, which scale with the magnitude of the acoustic modal displacement. The photoelastic perturbations propagate along the fiber axis with the frequency and wavenumber of the acoustic wave and may scatter and modulate optical fields. The effect of the photoelastic perturbations on guided light depends on the spatial overlap between their transverse profile and that of the optical mode. The position-averaged perturbations associated with radial modes are scalar, and their effect on guided light is independent of polarization. Torsional-radial acoustic modes, on the other hand, induce …

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Oct 2022 • Talanta

High throughput optical modulation biosensing for highly sensitive and rapid detection of biomarkers

Shmuel Burg, Shira Roth, Meir Cohen, Shira Avivi-Mintz, Michael Margulis, Hanan Rohana, Avi Peretz, Amos Danielli

Rapid, highly sensitive, and high-throughput detection of biomarkers at low concentrations is invaluable for early diagnosis of various diseases. In many highly sensitive immunoassays, magnetic beads are used to capture fluorescently labeled target molecules. The target molecules are then quantified by detecting the fluorescent signal from individual beads, which is time consuming and requires a complicated and expensive detection system. Here, we demonstrate a high-throughput optical modulation biosensing (ht-OMB) system, which uses a small permanent magnet to aggregate the beads into a small detection volume and eliminates background noise by steering a laser beam in and out of the cluster of beads. Shortening the aggregation, acquisition, and well-to-well scanning transition times enables reading a 96-well plate within 10 min. Using the ht-OMB system to detect human Interleukin-8, we …

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Oct 2022 • Biophysical Reviews 14 (5), 1141-1159, 2022

The use of EPR spectroscopy to study transcription mechanisms

L Hofmann, A Mandato, S Saxena, S Ruthstein

Electron paramagnetic resonance (EPR) spectroscopy has become a promising structural biology tool to resolve complex and dynamic biological mechanisms in-vitro and in-cell. Here, we focus on the advantages of continuous wave (CW) and pulsed EPR distance measurements to resolve transcription processes and protein-DNA interaction. The wide range of spin-labeling approaches that can be used to follow structural changes in both protein and DNA render EPR a powerful method to study protein-DNA interactions and structure–function relationships in other macromolecular complexes. EPR-derived data goes well beyond static structural information and thus serves as the method of choice if dynamic insight is needed. Herein, we describe the conceptual details of the theory and the methodology and illustrate the use of EPR to study the protein-DNA interaction of the copper-sensitive transcription factor, CueR.

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Oct 2022 • Journal of Applied Polymer Science

Polydopamine decorated carbon dots nanocomposite as an effective adsorbent for phenolic compounds

Moorthy Maruthapandi, Arumugam Saravanan, John HT Luong, Aharon Gedanken

Carbon dots (CDs) with an average diameter of 2.3 ± 0.5 nm were prepared from red cabbage by a facile one‐step hydrothermal process. The CDs and polydopamine (PDA) were then subjected to ultrasonication to form a polymer composite namely, PDA‐doped CDs (PDA@CDs). The PDA@CDs with an average size of 5 μm was proven as effective adsorbents for p‐chlorophenol (p‐CP) and p‐cyanophenol (p‐CNP) as two probing models. The adsorption capacity of PDA@CDs was estimated to be 153 mg/g for p‐CP and 178 mg/g for p‐CNP, compared favorably with those of various adsorbents used in the literature, only 24–123 mg/g. The PDA@CDs significantly improved the adsorption rate of the two phenols at neutral pH and room temperature. The adsorption kinetics was governed by the pseudo second‐order and intraparticle diffusion models. The PDA@CDs were reused as an active adsorbent …

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Oct 2022 • Applied Sciences

Kerr-Lens Mode-Locking: Numerical Simulation of the Spatio-Temporal Dynamics on All Time Scales

Idan Parshani, Leon Bello, Mallachi-Elia Meller, Avi Pe’er

We present a complete numerical analysis and simulation of the full spatio-temporal dynamics of Kerr-lens mode-locking in a laser. This dynamic, which is the workhorse mechanism for generating ultrashort pulses, relies on the intricate coupling between the spatial nonlinear propagation and the temporal nonlinear compression. Our numerical tool emulates the dynamical evolution of the optical field in the cavity on all time-scales: the fast time scale of the pulse envelope within a single round trip, and the slow time-scale between round-trips. We employ a nonlinear ABCD formalism that fully handles all relevant effects in the laser, namely—self focusing and diffraction, dispersion and self-phase modulation, and space-dependent loss and gain saturation. We confirm the validity of our model by reproducing the pulse-formation in all aspects: The evolution of the pulse energy, duration, and gain during the entire cavity buildup, demonstrating the nonlinear mode competition in full, as well as the dependence of the final pulse in steady state on the interplay between gain bandwidth, dispersion, and self-phase modulation. The direct observation of the nonlinear evolution of the pulse in space-time is a key enabler to analyze and optimize the Kerr-lens mode-locking operation, as well as to explore new nonlinear phenomena.

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Oct 2022 • Journal of Electroanalytical Chemistry

Ultra-low palladium engineered nickel sulfide heterostructure supported on 3D nickel foam as a highly efficient and stable electrocatalyst for water oxidation

Hari Krishna Sadhanala, Akanksha Gupta, Aharon Gedanken

Electrochemical water splitting (EWS) has been a crucial process in the production of green fuels (oxygen and hydrogen) for a sustainable energy economy. One of the key processes in the EWS is water oxidation or the oxygen evolution reaction (OER). It is highly desirable to create cost-effective, efficient, and robust electrocatalysts for OER. Here, we present ultra-low Pd doped NiS-NiS2 heterostructure on NF (0.1PdNiS/NF) grown in-situ by acid etching followed by a simple hydrothermal sulfurization method for excellent OER electrocatalytic activity in alkaline media. Interestingly, low overpotential of 275 mV is required for the 0.1PdNiS/NF to achieve a current density of 10 mAcm-2, which is less than both NiS/NF (385 mV) and commercial RuO2/NF (370 mV). Because of the strong electronic interaction between Pd and NiS, 0.1PdNiS/NF has a small Tafel slope of 65 mV/dec and has shown excellent durability for …

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Oct 2022 • ACS applied materials & interfaces

NiN-Passivated NiO Hole-Transport Layer Improves Halide Perovskite-Based Solar Cell

Anat Itzhak, Xu He, Adi Kama, Sujit Kumar, Michal Ejgenberg, Antoine Kahn, David Cahen

The interfaces between inorganic selective contacts and halide perovskites (HaPs) are possibly the greatest challenge for making stable and reproducible solar cells with these materials. NiOx, an attractive hole-transport layer as it fits the electronic structure of HaPs, is highly stable and can be produced at a low cost. Furthermore, NiOx can be fabricated via scalable and controlled physical deposition methods such as RF sputtering to facilitate the quest for scalable, solvent-free, vacuum-deposited HaP-based solar cells (PSCs). However, the interface between NiOx and HaPs is still not well-controlled, which leads at times to a lack of stability and Voc losses. Here, we use RF sputtering to fabricate NiOx and then cover it with a NiyN layer without breaking vacuum. The NiyN layer protects NiOx doubly during PSC production. Firstly, the NiyN layer protects NiOx from Ni3+ species being reduced to Ni2+ by Ar plasma …

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Oct 2022 • Advanced Engineering Materials

Printed Cu–Ag Phases Using Laser‐Induced Forward Transfer

Niv Gorodesky, Sharona Sedghani-Cohen, Ofer Fogel, Marc Altman, Gili Cohen-Taguri, Zvi Kotler, Zeev Zalevsky

Laser‐induced forward transfer (LIFT) is an additive manufacturing technique where short laser pulses are focused through a transparent substrate onto a thin, uniform, metal layer jetting micrometer‐scale droplets yielding high‐resolution 3D metal structures. Herein, LIFT printing from multilayered metal donors, and from compositional metal mixtures, is explored and presented. A comprehensive study of this sort has been lacking so far. LIFT printing from Cu–Ag structured donors is thoroughly studied. X‐ray diffraction (XRD) analysis reveals the formation of a metastable Cu–Ag phase reflecting the high cooling rate of the metal droplets. Tuning properties of the printed metal structures is made possible by controlling the pulse width and the donor layers’ properties. Longer pulses (10 ns) jetting from cosputtered donors yield better homogeneity than shorter pulses (1 ns) from donors made of distinct sputtered …

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Oct 2022 • Optics Express

Optical fiber point sensors based on forward Brillouin scattering

Keren Shemer, Gil Bashan, Elad Zehavi, Hilel Hagai Diamandi, Alon Bernstein, Kavita Sharma, Yosef London, David Barrera, Salvador Sales, Arik Bergman, Avi Zadok

Forward Brillouin scattering interactions support the sensing and analysis of media outside the cladding boundaries of standard fibers, where light cannot reach. Quantitative point-sensing based on this principle has yet to be reported. In this work, we report a forward Brillouin scattering point-sensor in a commercially available, off-the-shelf multi-core fiber. Pump light at the inner, on-axis core of the fiber is used to stimulate a guided acoustic mode of the entire fiber cross-section. The acoustic wave, in turn, induces photoelastic perturbations to the reflectivity of a Bragg grating inscribed in an outer, off-axis core of the same fiber. The measurements successfully analyze refractive index perturbations on the tenth decimal point and distinguish between ethanol and water outside the centimeter-long grating. The measured forward Brillouin scattering linewidths agree with predictions. The acquired spectra are unaffected by forward Brillouin scattering outside the grating region. The results add point-analysis to the portfolio of forward Brillouin scattering optical fiber sensors.

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Oct 2022 • Communications biology

Affinity microfluidics enables high-throughput protein degradation analysis in cell-free extracts

Lev Brio, Danit Wasserman, Efrat Michaely-Barbiro, Gal Barazany-Gal, Doron Gerber, Amit Tzur

Protein degradation mediated by the ubiquitin-proteasome pathway regulates signaling events in many physiological and pathological conditions. In vitro degradation assays have been instrumental in the understanding of how cell proliferation and other fundamental cellular processes are regulated. These assays are direct, time-specific and highly informative but also laborious, typically relying on low-throughput polyacrylamide gel-electrophoresis followed by autoradiography or immunoblotting. We present protein degradation on chip (pDOC), a MITOMI-based integrated microfluidic technology for discovery and analysis of proteins degradation in cell-free extracts. The platform accommodates hundreds of microchambers on which protein degradation is assayed quickly, simultaneously and using minute amounts of reagents in one or many physiochemical environments. Essentially, pDOC provides a sensitive …

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Oct 2022 • Scientific Reports

Non-contact optical in-vivo sensing of cilia motion by analyzing speckle patterns

Doron Duadi, Nadav Shabairou, Adi Primov-Fever, Zeev Zalevsky

Cilia motion is an indicator of pathological-ciliary function, however current diagnosis relies on biopsies. In this paper, we propose an innovative approach for sensing cilia motility. We present an endoscopic configuration for measuring the motion frequency of cilia in the nasal cavity. The technique is based on temporal tracking of the reflected spatial distribution of defocused speckle patterns while illuminating the cilia with a laser. The setup splits the optical signal into two channels; One imaging channel is for the visualization of the physician and another is, defocusing channel, to capture the speckles. We present in-vivo measurements from healthy subjects undergoing endoscopic examination. We found an average motion frequency of around 7.3 Hz and 9.8 Hz in the antero-posterior nasal mucus (an area rich in cilia), which matches the normal cilia range of 7–16 Hz. Quantitative and precise measurements of …

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Sep 2022 • Journal of Biomedical Optics

Non-invasive blood glucose sensing by machine learning of optic fiber-based speckle pattern variation

Deep Pal, Sergey Agadarov, Yevgeny Beiderman, Yafim Beiderman, Amitesh Kumar, Zeev Zalevsky

Significance: The ability to perform frequent non-invasive monitoring of glucose in the bloodstream is very applicable for diabetic patients.Aim: We experimentally verified a non-invasive multimode fiber-based technique for sensing glucose concentration in the bloodstream by extracting and analyzing the collected speckle patterns.Approach: The proposed sensor consists of a laser source, digital camera, computer, multimode fiber, and alternating current (AC) generated magnetic field source. The experiments were performed using a covered (with cladding and jacket) and uncovered (without cladding and jacket) multimode fiber touching the skin under a magnetic field and without it. The subject’s finger was placed on a fiber to detect the glucose concentration. The method tracks variations in the speckle patterns due to light interaction with the bloodstream affected by blood glucose.Results: The uncovered fiber …

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Sep 2022 • Small

Bridging 1D Inorganic and Organic Synthesis to Fabricate Ultrathin Bismuth‐Based Nanotubes with Controllable Size as Anode Materials for Secondary Li Batteries

Kai Zong, Tianzhi Chu, Dongqing Liu, Andleeb Mehmood, Tianju Fan, Waseem Raza, Arshad Hussain, Yonggui Deng, Wei Liu, Ali Saad, Jie Zhao, Ying Li, Doron Aurbach, Xingke Cai

The growth of ultrathin 1D inorganic nanomaterials with controlled diameters remains challenging by current synthetic approaches. A polymer chain templated method is developed to synthesize ultrathin Bi2O2CO3 nanotubes. This formation of nanotubes is a consequence of registry between the electrostatic absorption of functional groups on polymer template and the growth habit of Bi2O2CO3. The bulk bismuth precursor is broken into nanoparticles and anchored onto the polymer chain periodically. These nanoparticles react with the functional groups and gradually evolve into Bi2O2CO3 nanotubes along the chain. 5.0 and 3.0 nm tubes with narrow diameter deviation are synthesized by using branched polyethyleneimine and polyvinylpyrrolidone as the templates, respectively. Such Bi2O2CO3 nanotubes show a decent lithium‐ion storage capacity of around 600 mA h g−1 at 0.1 A g−1 after 500 cycles, higher …

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Sep 2022 • Journal of nanotheranostics

Antibody Delivery into the Brain by Radiosensitizer Nanoparticles for Targeted Glioblastoma Therapy

Omer Gal, Oshra Betzer, Liat Rousso-Noori, Tamar Sadan, Menachem Motiei, Maxim Nikitin, Dinorah Friedmann-Morvinski, Rachela Popovtzer, Aron Popovtzer

Background: Glioblastoma is the most lethal primary brain malignancy in adults. Standard of care treatment, consisting of temozolomide (TMZ) and adjuvant radiotherapy (RT), mostly does not prevent local recurrence. The inability of drugs to enter the brain, in particular antibody-based drugs and radiosensitizers, is a crucial limitation to effective glioblastoma therapy. Methods: Here, we developed a combined strategy using radiosensitizer gold nanoparticles coated with insulin to cross the blood–brain barrier and shuttle tumor-targeting antibodies (cetuximab) into the brain. Results: Following intravenous injection to an orthotopic glioblastoma mouse model, the nanoparticles specifically accumulated within the tumor. Combining targeted nanoparticle injection with TMZ and RT standard of care significantly inhibited tumor growth and extended survival, as compared to standard of care alone. Histological analysis of tumors showed that the combined treatment eradicated tumor cells, and decreased tumor vascularization, proliferation, and repair. Conclusions: Our findings demonstrate radiosensitizer nanoparticles that effectively deliver antibodies into the brain, target the tumor, and effectively improve standard of care treatment outcome in glioblastoma.

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