Regulation of band gap and localized surface plasmon resonance by loading Au nanorods on violet phosphene nanosheets for photodynamic/photothermal synergistic anti-infective therapy.

In the face of the serious threat to human health and the economic burden caused by bacterial antibiotic resistance, 2D phosphorus nanomaterials have been widely used as antibacterial agents. Violet phosphorus nanosheets (VPNSs) are an exciting bandgap-adjustable 2D nanomaterial due to their good physicochemical properties, yet the study of VPNS-based antibiotics is still in its infancy. Here, a composite of gold nanorods (AuNRs) loaded onto VPNS platforms (VPNS/AuNR) is constructed to maximize the potential of VPNSs for antimicrobial applications. The loading with AuNRs not only enhances the photothermal performance via a localized surface plasmon resonance (LSPR) effect, but also enhances the light absorption capacity due to the narrowing of the band gap of the VPNSs, thus increasing the ROS generation capacity. The results demonstrate that VPNS/AuNR exhibits outstanding antibacterial properties and good biocompatibility. Attractively, VPNS/AuNR is then extensively tested for treating skin wound infections, suggesting promising in vivo antibacterial and wound-healing features. Our findings may open a novel direction to develop a versatile VPNS-based treatment platform, which can significantly boost the progress of VPNS exploration.

Polyethyleneimine in designed nanocomposite based magnetic halloysite nanotubes for extraction and determination of gallic acid in green tea.

An innovative and simple nanocomposite denoted as MHNTs@PEI was synthesized for gallic acid (GA) analytical sample pretreatment. Polyethyleneimine (PEI) functionalized was binded onto magnetic halloysite nanotubes (MHNTs) to inhence adsorption capacity. MHNTs@PEI was obtained only through two steps modification (amination and PEI modification). Characterizations showed that there are layers of synthetic PEI on the tubular structure of the material and magnetic spheres on its surface, both indicating successful synthesis of the nanocomposite. Furthermore, the adsorption isotherms and kinetic modeling showed that the Langmuir model and pseudo-first-order model fit the adsorption data, respectively. MHNTs@PEI achieved an adsorption capacity of 158 mg·g-1. Overall, the abundant adsorption sites significantly improved the adsorption performance of the MHNTs@PEI. Regeneration tests demonstrated that the MHNTs@PEI exhibits effective adsorption, even after undergoing five consecutive cycles. Optimization of key parameters (ratio, volume of elution, elution time and frequency) in the process of adsorption and desorption was also conducted. The limit of detection (LOD) and that of the quantification (LOQ) were 0.19 and 0.63 µg·mL-1, respectively, and the recoveries were 95.67-99.43 %. Finally, the excellent magnetism (43.5 emu·g-1) and the adsorption feature of MHNTs@PEI enabled its successful utilization in analytical sample pretreatment through the extraction of GA from green tea.

Red blood cell membrane-camouflaged gold-core silica shell nanorods for cancer drug delivery and photothermal therapy.

Gold core mesoporous silica shell (AuMSS) nanorods are multifunctional nanomedicines that can act simultaneously as photothermal, drug delivery, and bioimaging agents. Nevertheless, it is reported that once administrated, nanoparticles can be coated with blood proteins, forming a protein corona, that directly impacts on nanomedicines' circulation time, biodistribution, and therapeutic performance. Therefore, it become crucial to develop novel alternatives to improve nanoparticles' half-life in the bloodstream. In this work, Polyethylenimine (PEI) and Red blood cells (RBC)-derived membranes were combined for the first time to functionalize AuMSS nanorods and simultaneously load acridine orange (AO). The obtained results revealed that the RBC-derived membranes promoted the neutralization of the AuMSS' surface charge and consequently improved the colloidal stability and biocompatibility of the nanocarriers. Indeed, the in vitro data revealed that PEI/RBC-derived membranes' functionalization also improved the nanoparticles' cellular internalization and was capable of mitigating the hemolytic effects of AuMSS and AuMSS/PEI nanorods. In turn, the combinatorial chemo-photothermal therapy mediated by AuMSS/PEI/RBC_AO nanorods was able to completely eliminate HeLa cells, contrasting with the less efficient standalone therapies. Such data reinforce the potential of AuMSS nanomaterials to act simultaneously as photothermal and chemotherapeutic agents.

Biosynthesis of CuTe Nanorods with Large Molar Extinction Coefficients for NIR-II Photoacoustic Imaging.

Photoacoustic imaging (PAI) in the second near-infrared region (NIR-II), due to deeper tissue penetration and a lower background interference, has attracted widespread concern. However, the development of NIR-II nanoprobes with a large molar extinction coefficient and a high photothermal conversion efficiency (PCE) for PAI and photothermal therapy (PTT) is still a big challenge. In this work, the NIR-II CuTe nanorods (NRs) with large molar extinction coefficients ((1.31 ± 0.01) × 108 cm-1·M-1 at 808 nm, (7.00 ± 0.38) × 107 cm-1·M-1 at 1064 nm) and high PCEs (70% at 808 nm, 48% at 1064 nm) were synthesized by living Staphylococcus aureus (S. aureus) cells as biosynthesis factories. Due to the strong light-absorbing and high photothermal conversion ability, the in vitro PA signals of CuTe NRs were about 6 times that of indocyanine green (ICG) in both NIR-I and NIR-II. In addition, CuTe NRs could effectively inhibit tumor growth through PTT. This work provides a new strategy for developing NIR-II probes with large molar extinction coefficients and high PCEs for NIR-II PAI and PTT.

Pectin wrapped halloysite nanotube reinforced Polycaprolactone films for potential wound healing application.

The current research work focuses on preparing the polycaprolactone (PCL) based nanocomposite films embedded with surface modified Halloysite Nanotube (HNT). The avenue of the study is to unravel the applicability of polymer nanocomposites for wound healing. The flexible property of HNT was taken as the major force to accomplish the addition of biopolymer pectin onto its surface. Functionalization of HNT with pectin has certainly enhanced its binding nature with the polymer. The PCL nanocomposite films were characterized by several promising techniques such as FTIR, XRD, DSC-TGA, FESEM, TEM, AFM, and mechanical properties were too examined along. When compared to the plane PCL film, the nanocomposite films manifested favorable results in terms of mechanical and chemical properties. Additionally, biometric studies such as in-vitro swelling, enzymatic degradation, and hemolysis performed on the films gave extremely good results. The haemolytic percentage recorded for the films exhibited a steady decrease with increasing amount of nanofillers. The MTT assay showed cell proliferation and its increase as the embedded HNT is more in the matrix. Wound closure study performed on NIH3T3 cell line with 1, 3 and 5wt% of films has given a strong proof for the involvement of polymer and HNT in the healing procedure.

Synergistic chemo-photothermal therapy using gold nanorods supported on thiol-functionalized mesoporous silica for lung cancer treatment.

Cancer therapy necessitates the development of novel and effective treatment modalities to combat the complexity of this disease. In this project, we propose a synergistic approach by combining chemo-photothermal treatment using gold nanorods (AuNRs) supported on thiol-functionalized mesoporous silica, offering a promising solution for enhanced lung cancer therapy. To begin, mesoporous MCM-41 was synthesized using a surfactant-templated sol-gel method, chosen for its desirable porous structure, excellent biocompatibility, and non-toxic properties. Further, thiol-functionalized MCM-41 was achieved through a simple grafting process, enabling the subsequent synthesis of AuNRs supported on thiol-functionalized MCM-41 (AuNR@S-MCM-41) via a gold-thiol interaction. The nanocomposite was then loaded with the anticancer drug doxorubicin (DOX), resulting in AuNR@S-MCM-41-DOX. Remarkably, the nanocomposite exhibited pH/NIR dual-responsive drug release behaviors, facilitating targeted drug delivery. In addition, it demonstrated exceptional biocompatibility and efficient internalization into A549 lung cancer cells. Notably, the combined photothermal-chemo therapy by AuNR@S-MCM-41-DOX exhibited superior efficacy in killing cancer cells compared to single chemo- or photothermal therapies. This study showcases the potential of the AuNR@S-MCM-41-DOX nanocomposite as a promising candidate for combined chemo-photothermal therapy in lung cancer treatment. The innovative integration of gold nanorods, thiol-functionalized mesoporous silica, and pH/NIR dual-responsive drug release provides a comprehensive and effective therapeutic approach for improved outcomes in lung cancer therapy. Future advancements based on this strategy hold promise for addressing the challenges posed by cancer and transforming patient care.

Selective enhanced cytotoxicity of amino acid deprivation for cancer therapy using thermozyme functionalized nanocatalyst.

BACKGROUND: Enzyme therapy based on differential metabolism of cancer cells has demonstrated promising potential as a treatment strategy. Nevertheless, the therapeutic benefit of reported enzyme drugs is compromised by their uncontrollable activity and weak stability. Additionally, thermozymes with high thermal-stability suffer from low catalytic activity at body temperature, preventing them from functioning independently. RESULTS: Herein, we have developed a novel thermo-enzymatic regulation strategy for near-infrared (NIR)-triggered precise-catalyzed photothermal treatment of breast cancer. Our strategy enables efficient loading and delivery of thermozymes (newly screened therapeutic enzymes from thermophilic bacteria) via hyaluronic acid (HA)-coupled gold nanorods (GNRs). These nanocatalysts exhibit enhanced cellular endocytosis and rapid enzyme activity enhancement, while also providing biosafety with minimized toxic effects on untargeted sites due to temperature-isolated thermozyme activity. Locally-focused NIR lasers ensure effective activation of thermozymes to promote on-demand amino acid deprivation and photothermal therapy (PTT) of superficial tumors, triggering apoptosis, G1 phase cell cycle arrest, inhibiting migration and invasion, and potentiating photothermal sensitivity of malignancies. CONCLUSIONS: This work establishes a precise, remotely controlled, non-invasive, efficient, and biosafe nanoplatform for accurate enzyme therapy, providing a rationale for promising personalized therapeutic strategies and offering new prospects for high-precision development of enzyme drugs.

Size Dependence of Gold Nanorods for Efficient and Rapid Photothermal Therapy.

In recent years, gold nanomaterials have become a hot topic in photothermal tumor therapy due to their unique surface plasmon resonance characteristics. The effectiveness of photothermal therapy is highly dependent on the shape and size of gold nanoparticles. In this work, we investigate the photothermal therapeutic effects of four different sizes of gold nanorods (GNRs). The results show that the uptake of short GNRs with aspect ratios 3.3-3.5 by cells is higher than that of GNRs with aspect ratios 4-5.5. Using a laser with single pulse energy as low as 28 pJ laser for 20 s can induce the death of liver cancer cells co-cultured with short GNRs. Long GNRs required twice the energy to achieve the same therapeutic effect. The dual-temperature model is used to simulate the photothermal response of intracellular clusters irradiated by a laser. It is found that small GNRs are easier to compact because of their morphological characteristics, and the electromagnetic coupling between GNRs is better, which increases the internal field enhancement, resulting in higher local temperature. Compared with a single GNR, GNR clusters are less dependent on polarization and wavelength, which is more conducive to the flexible selection of excitation laser sources.

A tumor-targeted and enzyme-responsive gold nanorod-based nanoplatform with facilitated endo-lysosomal escape for synergetic photothermal therapy and protein therapy.

To tackle the obstacles related to tumor targeting and overcome the limitations of single treatment models, we have developed a nanoplatform that is both tumor-targeted and enzyme-responsive. This nanoplatform integrates photothermal gold nanorods (AuNRs) and protein drugs into a single system. This nanosystem, known as AuNRs@HA-mPEG-Deta-LA, was fabricated by modifying gold nanorods (AuNRs) with a polymeric ligand called hyaluronic acid-grafted-(mPEG/diethylenetriamine-conjugated-lipoic acid). The purpose of this fabrication was to load cytochrome c (CC) and utilize it for the synergetic protein-photothermal therapy of cancer. The resulting nanoplatform exhibited a high efficiency in loading proteins and demonstrated excellent stability in different biological environments. Additionally, CC-loaded AuNRs@HA-mPEG-Deta-LA not only enabled localized hyperthermia for photothermal therapy (PTT) with laser irradiation but also facilitated the release of CC under the action of hyaluronidase, an enzyme known to be overexpressed in tumor cells. The confocal imaging results demonstrated that the presence of a specific polymeric ligand on this nanoparticle enhances the internalization of CD44-positive cancer cells, accelerates endo/lysosomal escape, and facilitates the controlled release of CC within the cells. Furthermore, the results of the MTT assay also showed that AuNRs@HA-mPEG-Deta-LA as a protein nanocarrier demonstrated excellent biocompatibility. Importantly, this synergistic therapeutic strategy effectively induced apoptosis in A549 cancer cells by increasing the intracellular concentration of CC and utilizing the photothermal conversion of AuNRs, which was observed to be more effective compared to using only protein therapy or PTT. Therefore, this study showcased a nanoplatform based on AuNRs that has great potential for tumor-targeted protein delivery in combination with PTT in cancer treatment.

Eco-friendly bamboo pulp foam enabled by chitosan and phytic acid interfacial assembly of halloysite nanotubes: Toward flame retardancy, thermal insulation, and sound absorption.

Lightweight, porous cellulose foam is an attractive alternative to traditional petroleum-based products, but the intrinsic flammability impedes its use in construction. Herein, an environmentally friendly strategy for scalable fabrication of flame-retardant bamboo pulp foam (BPF) using a foam-forming technique followed by low-cost ambient drying is reported. In the process, a hierarchical structure of halloysite nanotubes (HNT) was decorated onto bamboo pulp fibers through layer-by-layer assembling of chitosan (CS) and phytic acid (PA). This modification retained the highly porous microcellular structure of the resultant BPF (92 %-98 %). It improved its compressive strength by 228.01 % at 50 % strain, endowing this foam with desired thermal insulation properties and sound absorption coefficient comparable to commercial products. More importantly, this foam possessed exceptional flame retardancy (47.05 % reduction in the total heat release and 95.24 % reduction in the total smoke production) in cone calorimetry, and it showed excellent extinguishing performance, indicating considerably enhanced fire safety. These encouraging results suggest that the flame retardant BPF has the potential to serve as a renewable and cost-effective alternative to traditional foam for applications in acoustic and thermal insulation.

Glucose oxidase and ruthenium nanorods-embedded self-healing polyvinyl alcohol/polyethylene imine hydrogel for simultaneous photothermal/photodynamic/starvation therapy and skin reconstruction.

Tumor recurrence and wound healing represent significant burdens for tumor patients after the surgical removal of melanomas. Wound dressings with wound healing and anticancer therapeutic abilities could help to solve these issues. Thus, a hybrid hydrogel made of polyvinyl alcohol (PVA) and polyethylene imine (PEI) was prepared by cross-linking imine bond and boronic acid bond. This hydrogel was loaded with ruthenium nanorods (Ru NRs) and glucose oxidase (GOx) and named as nanocomposite hydrogel (Ru/GOx@Hydrogel), exhibiting remarkable photothermal/photodynamic/starvation antitumor therapy and wound repair abilities. Ru NRs are bifunctional phototherapeutic agents that simultaneously exhibit intrinsic photothermal and photodynamic functions. Three-dimensional composite hydrogel loaded with GOx can also consume glucose in the presence of O2 during tumor starvation therapy. Near-infrared (NIR) light-triggered hyperthermia can not only promote the consumption of glucose, but also facilitate the ablation of residual cancer cells. The antitumor effect of the Ru/GOx@Hydrogel resulted in significant improvements, compared to those observed with either phototherapy or starvation therapy alone. Additionally, the postoperative wound was substantially healed after treatment with Ru/GOx@Hydrogel and NIR irradiation. Therefore, the Ru/GOx@Hydrogel can be used as a multi-stimulus-responsive nanoplatform that could facilitate on-demand controlled drug release, and be used as a promising postoperative adjuvant in combination therapy.

Preparation and photothermal therapy of gold nanorods modified by Belamcanda chinensis (L.) DC polysaccharide.

In recent years, the application of nanoparticles formed by coupling metal nanomaterials of photothermal therapy with polysaccharides as modified carriers in the targeted treatment of liver cancer has attracted extensive attention. In the present work, an undescribed homogeneous polysaccharide BCP50-2 was obtained from Belamcanda chinensis (L.) DC. The structural analysis displayed that BCP50-2 contained galactose and a small amount of arabinose, and was mainly composed of six monosaccharide residues: →3,5)-α-l-Araf-(1→, →4)-ß-d-Galp-(1→, →4,6)-ß-d-Galp-(1→, →3)-α-l-Galp-(1→, terminal α-l-Araf, and terminal ß-d-Galp. To enhance the antitumor activity of BCP50-2, BCP50-2-AuNRs were prepared by coupling BCP50-2 with gold nanorods for the treatment of liver cancer. BCP50-2-AuNRs were rod-shaped with a long diameter of 26.8 nm and had good photothermal conversion effects. Under near-infrared (NIR) light irradiation, BCP50-2-AuNRs possessed photothermal effects and suppressed the growth of HepG2, A549, and MCF-7 cells. In addition, BCP50-2-AuNRs inhibited the development of liver cancer by inducing cell apoptosis, arresting the cell cycle in G2/M phases, and inhibiting cell migration. Moreover, BCP50-2-AuNRs inhibited tumor proliferation, migration, and angiogenesis in zebrafish. In summary, BCP50-2-AuNRs may be potentially useful for cancer treatment.

Promoting Intratumoral Drug Accumulation by Bio-Membrane Regulated Active Targeting for Tumor Photothermal Therapy.

Introduction: Insufficient tumor permeability and inadequate nanoparticle retention continue to be significant limitations in the efficacy of anti-tumor drug therapy. Numerous studies have focused on enhancing tumor perfusion by improvement of tumor-induced endothelial leakage, often known as the enhanced permeability and retention (EPR) effect. However, these approaches have produced suboptimal therapeutic outcomes and have been associated with significant side effects. Therefore, in this study, we prepared tumor cell membrane-coated gold nanorods (GNR@TM) to enhance drug delivery in tumors through homogeneous targeting of tumor cell membranes and in situ real-time photo-controlled therapy. Methods: Here, we fabricated GNR@TM, and characterized it using various techniques including Ultraviolet-Visible (UV-Vis) spectrophotometer, particle size analysis, potential measurement, and transmission electron microscopy (TEM). The cellular uptake and cytotoxicity of GNR@TM were analyzed by flow cytometry, confocal laser scanning microscopy (CLSM), TEM, CCK8 assay and live/dead staining. Tissue drug distribution was determined by inductively coupled plasma mass spectrometry (ICP-MS) and immunofluorescence staining. Furthermore, to evaluate the therapeutic effect, mice bearing MB49 tumors were intravenously administered with GNR@TM. Subsequently, near-infrared (NIR) laser therapy was performed, and the mice's tumor growth and body weight were monitored. Results: The tumor cell membrane coating endowed GNR@TM with extended circulation time in vivo and homotypic targeting to tumor, thereby enhancing the accumulation of GNR@TM within tumors. Upon 780 nm laser, GNR@TM exhibited excellent photothermal conversion capability, leading to increased tumor vascular leakage. This magnification of the EPR effect induced by NIR laser further increased the accumulation of GNR@TM at the tumor site, demonstrating strong antitumor effects in vivo. Conclusion: In this study, we successfully developed a NIR-triggered nanomedicine that increased drug accumulation in tumor through photo-controlled therapy and homotypic targeting of the tumor cell membrane. GNR@TM has been demonstrated effective suppression of tumor growth, excellent biocompatibility, and significant potential for clinical applications.

Theoretical Estimation of Tissue Thermal Response and Associated Thermal Damage During Gold Nanorod-enhanced Photothermal Therapy of Tumors.

In the present work, we implemented a computational framework of in vivo gold nanorod (GNR)-enhanced photothermal therapy (PTT) for tumor treatment. The temperature-dependent thermophysical properties of biological tissue and the optical properties of both GNRs and the biological media were included. The latter were modulated during the treatment simulation to account for their variation, from the native to the coagulated state. The contribution of tissue injury-dependent blood perfusion was also considered. The developed model allowed for the estimation of temperature distribution during the photothermal procedure at different procedural settings and amounts of GNRs embedded in the tumor region (i.e., 12.5 µg, 25 µg, and 50 µg). Furthermore, the influence of GNRs on thermal injury, estimated with different damage models, was assessed. The inclusion of GNRs in the tumor entailed an increment of maximum tissue temperature, and faster heating kinetics, as witnessed by the lower time needed to reach complete thermal damage at the tumor center. The percentage of tumor thermal damage evaluated at the end of the simulated treatment was 48%, 69%, and 90%, for PTT in the presence of 12.5 µg, 25 µg, and 50 µg of GNRs, respectively.Clinical Relevance-This establishes that simulation-based tools, modeling the tissue properties variation during the photothermal treatment, can serve as promising preplanning platforms for nanoparticle-assisted light therapies.

Effective Distribution of Gold Nanorods in Ordered Thick Mesoporous Silica: A Choice of Noninvasive Theranostics.

Porous silica coated gold nanorod core-shell structures demonstrate a multifunctional role in bioimaging, drug delivery, and cancer therapeutics applications. Here, we address a new approach for effective distribution of gold nanorods (GNRs) in a mesoporous silica (MS) shell, viz., one nanorod in one silica particle (GMS). We have studied that silica coating presents major advantages for the better biocompatibility and stability of GNRs. In this study, two different thicknesses of silica shell over GNRs have been discussed as per the application's need; GNRs in thin silica (11 nm) are fit for phototherapy and bioimaging, whereas thick and porous silica (51 nm) coated gold nanorods are suitable for triggered drug delivery and theranostics. However, effective distribution of GNRs in ordered architecture of thick mesoporous silica (MS, more than 50 nm thickness) with high surface area (more than 1000 m2/g) is not well understood so far. Here, we present methodical investigations for uniform and highly ordered mesoporous silica coating over GNRs with tunable thickness (6 to 51 nm). Judicious identification and optimization of different reaction parameters like concentrations of silica precursor (TEOS, 1.85-43.9 mM), template (CTAB, 0.9-5.7 mM), effect of temperature, pH (8.6-10.8), stirring speed (100-400 rpm), and, most importantly, the mode of addition of TEOS with GNRs have been discussed. Studies with thick, porous silica coated GNRs simplify the highest ever reported surface area (1100 m2/g) and cargo capacity (57%) with better product yield (g/batch). First and foremost, we report a highly scalable (more than 500 mL) and rapid direct deposition of an ordered MS shell around GNRs. These engineered core-shell nanoparticles demonstrate X-ray contrast property, synergistic photothermal-chemotherapeutics, and imaging of tumor cell (96% cell death) due to released fluorescent anticancer drug molecules and photothermal effect (52 °C) of embedded GNRs. A deeper insight into their influence on the architectural features and superior theranostics performances has been illustrated in detail. Hence, these findings indicate the potential impact of individual GMS for image guided combination therapeutics of cancer.

Gold Nanorod/Titanium Dioxide Hybrid Nanoparticles for Plasmon-Enhanced Near-Infrared Photoproduction of Hydroxyl Radicals and Photodynamic Therapy.

Gold nanoparticles, such as nanorods (AuNRs), present exceptionally high absorption cross sections that can be tuned to the near-infrared (NIR), the optimal window for light penetration in biological tissues. This makes them valuable photosensitizers for the treatment of cancer using photothermal therapy, where absorbed light energy is converted into heat. In addition, there is a strong interest in using hot electron carriers generated in AuNRs by NIR irradiation to produce cytotoxic radical oxygen species in order to enhance the efficiency of the phototherapy. Here, we show that hybrid nanoparticles composed of AuNRs with TiO2 deposited at their extremities are efficient sensitizers to produce hydroxyl radical species under NIR irradiation. We attribute this phenomenon to the transfer of hot electrons generated from the plasmon excitation in AuNR to the TiO2 tips, followed by reduction of dioxygen. We then functionalize these hybrid AuNR/TiO2 nanoparticles with block poly(ethylene glycol)-phosphonate polymer ligands to stabilize them in a physiological medium. We finally demonstrate that the photodynamic effect induces cell death upon irradiation with a greater efficiency than the photothermal effect alone.

Regulating oxygen vacancies and hydroxyl groups of α-MnO2 nanorods for enhancing post-plasma catalytic removal of toluene.

Although nonthermal plasma (NTP) technology has high removal efficiency for volatile organic compounds (VOCs), it has limited carbon dioxide (CO2) selectivity, which hinders its practical application. In this study, α-MnO2 nanorods with tunable oxygen vacancies and hydroxyl groups were synthesized by two-step hydrothermal process to enhance their activity for deep oxidation of toluene. Hydrochloric acid (HCl) was used to assist in synthesis of α-MnO2 nanorods with tunable oxygen vacancies, furtherly, more hydroxyl groups were introduced to HCl-assisted synthesized α-MnO2 by K+ supplement. The results showed that the as-synthesized nanorods exhibited superior activity, improved by nearly 30% removal efficiency of toluene compared to pristine MnO2 at SIE = 339 J/L, and reaching high COx selectivity of 72% at SIE = 483 J/L, successfully promoting the deep oxidation of toluene. It was affirmed that oxygen vacancies played an important role in toluene conversion, improving the conversion of ozone (O3) and resulting in higher mobility of surface lattice oxygen species. Besides, the enhancement of deep oxidation performance was caused by the increase of hydroxyl groups concentration. In-situ DRIFTS experiments revealed that the adsorbed toluene on catalyst surface was oxidized to benzyl alcohol by surface lattice oxygen, and hydroxyl groups were also found participating in toluene adsorption. Overall, this study provides a new approach to designing catalysts for deep oxidation of VOCs.

Pilot Study of Cytoprotective Mechanisms of Selenium Nanorods (SeNrs) under Ischemia-like Conditions on Cortical Astrocytes.

The cytoprotective properties of the trace element selenium, its nanoparticles, and selenium nanocomplexes with active compounds are shown using a number of models. To date, some molecular mechanisms of the protective effect of spherical selenium nanoparticles under the action of ischemia/reoxygenation on brain cells have been studied. Among other things, the dependence of the effectiveness of the neuroprotective properties of nanoselenium on its diameter, pathways, and efficiency of penetration into astrocytes was established. In general, most research in the field of nanomedicine is focused on the preparation and study of spherical nanoparticles of various origins due to the ease of their preparation; in addition, spherical nanoparticles have a large specific surface area. However, obtaining and studying the mechanisms of action of nanoparticles of a new form are of great interest since nanorods, having all the positive properties of spherical nanoparticles, will also have a number of advantages. Using the laser ablation method, we managed to obtain and characterize selenium nanorods (SeNrs) with a length of 1 µm and a diameter of 100 nm. Using fluorescence microscopy and inhibitory analysis, we were able to show that selenium nanorods cause the generation of Ca2+ signals in cortical astrocytes in an acute experiment through the mobilization of Ca2+ ions from the thapsigargin-sensitive pool of the endoplasmic reticulum. Chronic use of SeNrs leads to a change in the expression pattern of genes encoding proteins that regulate cell fate and protect astrocytes from ischemia-like conditions and reoxygenation through the inhibition of a global increase in the concentration of cytosolic calcium ([Ca2+]i). An important component of the cytoprotective effect of SeNrs during ischemia/reoxygenation is the induction of reactive A2-type astrogliosis in astrocytes, leading to an increase in both baseline and ischemia/reoxygenation-induced phosphoinositide 3-kinase (PI3K) activity and suppression of necrosis and apoptosis. The key components of this cytoprotective action of SeNrs are the actin-dependent process of endocytosis of nanoparticles into cells and activation of the Ca2+ signaling system of astrocytes.

Drug-Free Antimicrobial Nanomotor for Precise Treatment of Multidrug-Resistant Bacterial Infections.

Manufacturing heteronanostructures with specific physicochemical characteristics and tightly controllable designs is very appealing. Herein, we reported NIR-II light-driven dual plasmonic (AuNR-SiO2-Cu7S4) antimicrobial nanomotors with an intended Janus configuration through the overgrowth of copper-rich Cu7S4 nanocrystals at only one high-curvature site of Au nanorods (Au NRs). These nanomotors were applied for photoacoustic imaging (PAI)-guided synergistic photothermal and photocatalytic treatment of bacterial infections. Both the photothermal performance and photocatalytic activity of the nanomotors are dramatically improved owing to the strong plasmon coupling between Au NRs and the Cu7S4 component and enhanced energy transfer. The motion behavior of nanomotors promotes transdermal penetration and enhances the matter-bacteria interaction. More importantly, the directional navigation and synergistic antimicrobial activity of the nanomotors could be synchronously driven by NIR-II light. The marriage of active motion and enhanced antibacterial activity resulted in the expected good antibacterial effects in an abscess infection mouse model.

Biomimetic Gold Nanorods Modified with Erythrocyte Membranes for Imaging-Guided Photothermal/Gene Synergistic Therapy.

Pancreatic cancer (PC) is one of the most malignant cancers that develops rapidly and carries a poor prognosis. Synergistic cancer therapy strategy could enhance the clinical efficacy compared to either treatment alone. In this study, gold nanorods (AuNRs) were used as siRNA delivery vehicles to interfere with the oncogenes of KRAS. In addition, AuNRs were one of anisotropic nanomaterials that can absorb near-infrared (NIR) laser and achieve rapid photothermal therapy for malignant cancer cells. Modification of the erythrocyte membrane and antibody Plectin-1 occurred on the surface of the AuNRs, making them a promising target nanocarrier for enhancing antitumor effects. As a result, biomimetic nanoprobes presented advantages in biocompatibility, targeting capability, and drug-loading efficiency. Moreover, excellent antitumor effects have been achieved by synergistic photothermal/gene treatment. Therefore, our study would provide a general strategy to construct a multifunctional biomimetic theranostic multifunctional nanoplatform for preclinical studies of PC.