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Gel chromatography is used to separate single-chirality and selective-diameter SWCNTs. We also explore the use of photothermal therapy and biosensor applications based on single-chirality, selected-diameter, and unique geometric shape.

A key challenge for nanomedicines in clinical application is to reduce the dose while achieving excellent efficacy, which has attracted extensive attention in dose toxicity and potential risks. It is thus necessary to reasonably design nanomedicine with high-efficiency targeting and accumulation. Here, we designed and synthesized a tetragonal bismuthene-based "all-in-one" composite nanosystem (TPP-Bi@PDA@CP) with two-stage targeting, multimodal imaging, photothermal therapy, and immune enhancement functions. Through the elaborate design of its structure, the composite nanosystem possesses multiple properties including (i) two-stage targeting function of hepatoma cells and mitochondria [the aggregation at the tumor site is 2.63-fold higher than that of traditional enhanced permeability and retention (EPR) effect]; (ii) computed tomography (CT) contrast-enhancement efficiency as high as ∼51.8 HU mL mg

For most cancers, multimodal cancer synergistic therapy is far more effective than monotherapy. Herein, a multifunctional nanocarrier based on lentinan (LTN) in situ functionalized molybdenum disulfide nanoflowers (MoS2@LTN NFs) is developed by a simple hydrothermal method together with the in situ surface modification strategy. We utilized them to load chemotherapeutic drug gemcitabine (GEM) for in vitro and in vivo chemo-photothermal (Chemo-PTT) therapy. The results show that MoS2@LTN NFs have the following characteristics: (1) the in situ encapsulated LTN can affect the crystal structure of MoS2, and the light absorption capacity of MoS2@LTN is 1.26 times higher than that of pure MoS2; (2) it could achieve different drug release behaviors by dual stimulation with acidic pH and NIR laser irradiation; (3) in vivo experiments demonstrated that synergistic Chemo-PTT therapy achieved by using MoS2@LTN-GEM has a more favorable therapeutic effect than monotherapy. Accordingly, MoS2@LTN NFs could be developed as promising nanocarriers for synergistic therapy.

Speculated temperature has induced/reversed the oxidation of SDS-dispersed SWCNTs in water, in which the oxidation triggers the reorganization of SDS structure on SWCNTs to afford selective adsorpt...

Single-walled carbon nanotubes (SWNTs) with a toroidal/coiled geometry-shaped structure sustain innovative preference to future technology material. The toroidal shape can be used in designing nanoelectronic devices for various prospective applications such as tactile sensors, electromagnetic absorbers, and energy storage devices. In this study, we demonstrate the fabrication of toroidal geometry shapes of metallic (m-) and semiconducting (s-) SWNTs, which can be revealed by simply mixing a few solutions in the correct ratio, both oil-in-water (hydrophobic) and water-in-oil (hydrophilic) emulsion processes. Herein, the letter communicates the formation of pure m- and s-SWNTs (metallic and semiconducting) by annular, obtained from gel column chromatography, via the emulsion approach. We have also studied the surfactant sodium dodecyl sulfate removal of sorted species from a gel column by a simple method named as chloroform/methanol/water extraction.

By delivering the idea of green and safe hydrogen energy and novel photothermal therapy to the biomedical field, engineering of therapeutic nanomaterials for treatment of major diseases (such as cancer) holds great significance. In this work, a novel PdMo bimetallene was synthesized by a solvothermal reduction method, and it was explored and applied in the field of anti-tumor therapy for the first time. The absorption peak of the PdMo bimetallene can be precisely adjusted in the NIR biological window (700-1350 nm) only by changing the synthesis time. At the same time, it also shows strong light absorption and high photothermal conversion efficiency. Specifically, the photothermal conversion efficiencies at 808 nm, 980 nm and 1064 nm are 43.1%, 51.7% and 69.15%, respectively. Surprisingly, a PdMo bimetallene is an efficient catalyst, which can effectively promote hydrogen production from the hydrolysis of ammonia borane (AB) under acidic and photothermal conditions. Benefitting from these excellent properties, a multifunctional composite nano therapeutic agent (PdMo@AB@HA) was developed via layer-by-layer surface modification with AB and hyaluronic acid (HA). In this way, the synergistic PTT/hydrogen therapy of PdMo@AB@HA composite nanosheets in the NIR-I and NIR-II windows (808 nm, 980 nm, and 1064 nm) on mouse tumor xenografts of different depths was realized. Furthermore, the controlled release of hydrogen, targeted endocytosis, efficient eradication of tumors of different depths and high biosafety were systematically proved in vitro and in vivo. This work not only provides a novel and efficient theranostic nanoplatform for efficient cancer theranostics, but also provides a new strategy for the development of safe and efficient new anti-tumor therapies.

In this work, we report a new mixed-extractor strategy to improve the sorting yield of large-diameter semiconducting single-walled carbon nanotubes (s-SWCNTs) with high purity. In the new mixed-extractor strategy, two kinds of conjugated polymers with different rigidity, poly(9,9-n-dihexyl-2,7-fluorene-alt-9-phenyl-3,6-carbazole) (PDFP) and poly(9,9-dioctylfluorene-alt-benzothiadiazole) (P8BT), are used to sort large-diameter s-SWCNTs through two simple sonication processes. To our surprise, although PDFP itself shows no selectivity toward s-SWCNTs, it can greatly enhance the sorting yield of P8BT. Using the PDFP/P8BT mixed-extractor method, the yield of sorted s-SWCNTs has been enhanced by 5 times with a purity above 99 % in comparison to that using P8BT single-extractor method. In addition, the photoluminescence (PL) excitation maps shows that the PDFP/P8BT mixed-extractor system not only enhances the sorting yield substantially, but also tends to be enrichment of (15,4) SWCNTs with the diameter of 1.36 nm.

Development of high photothermal performance and biocompatible nanotherapeutic agents is of great importance for photothermal cancer treatment. In this paper, we have developed lentinan decorated tungsten oxide nanorods (W18O49@LTN NRs) via a mild one-step solvothermal route. Owing to the numerous surface hydroxyl groups of polymer chains, the presence of lentinan layer in the surface of W18O49 NRs lead to good biocompatibility. The lentinan layer also affects the crystal structure of W18O49 and improves near-infrared absorption (~1.7 × 109 M−1 cm−1 at 980 nm), which is two orders of higher than previously reported PEGylated W18O49 nanowires. Even under near-infrared (NIR) laser irradiation at a very low power density of 0.4 W/cm2, the temperature of W18O49@LTN NRs aqueous dispersion (125 μg/mL) could increase by 15.1 °C. The photothermal conversion efficiency of W18O49@LTN NRs reaches 33.86%, which is higher than previously reported WO3−x hierarchical nanostructures (28.1%). Importantly, when cancer cells were treated with W18O49@LTN NRs (200 μg/mL) and 980 nm laser (0.4 W/cm2), a significant photo-induced cell killing behavior was observed. This work demonstrates that W18O49@LTN NRs have the potential for precise cancer treatment.

Silkworm fibers have attracted widespread attention for their superb glossy texture and promising mechanical performance. The mechanical properties can be reinforced with carbon nanofillers, particularly carbon nanotubes (CNTs), depending on the CNT content in the silk fibers. In order to increase the CNT content, lignosulfonate (LGS) was used as a surfactant to ameliorate the CNT solubility, dispersibility, and biocompatibility. The resulting CNT/LGS nano-composite was further processed through an additional purification method to remove excess surfactant and enhance the CNT/LGS ratio. Then the purified biocompatible single and multiple-walled CNTs were fed to silkworms, leading to a large CNT content in the resulting silk fibers. Reinforced silk fibers were produced with a mechanical strength as high as 1.07 GPa and a strain of 16.8%. The toughness modulus is 1.69 times than that of the unpurified group. The CNT-embedded silk fibers were characterized via Raman spectrometry and thermogravimetric analysis (TGA), demonstrating that the CNT content in the silk fibers increased 1.5-fold in comparison to the unpurified group. The increased CNT content not only contributed to the self-assembly into buffering knots of silk fibers, but it also enhanced the conductivity of graphitized silk. Our coating and purification strategies provide a potential facile way to obtain natural silk fibers with high mechanical performance.

Efficient selective extraction of semiconducting single-walled carbon nanotubes (s-SWCNTs) from as-synthesized SWCNTs is essential for their electronic and photovoltaic applications. In this study, we used a relatively simple copolymer backbone structure of poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-thiophene] (PFT) for the selective extraction of s-SWCNTs from HiPCO SWCNTs. The absorption and Raman spectroscopies indicated that the PFT-sorted s-SWCNTs had high purity which was far beyond the sensitivity of the spectrometers. Photoluminescence excitation spectroscopy showed that PFT mainly extracted the chiralities of (n,m)=(9,5), (8,6), (7,5), and (10,5) s-SWCNTs with the ratios of about 53.1%, 24.8%, 11.5%, and 10.5%, respectively. Both steady-state and transient optical spectroscopies suggested that there was a strong interaction between PFT and s-SWCNTs. Molecular dynamics simulation results agreed well with the experimental data. Additionally, the photoinduced energy transfer behavior of the PFT-wrapped s-SWCNT resultant hybrid was assessed. This work indicated that the prepared PFT-wrapped s-SWCNT hybrid material was attractive for organic photovoltaic devices.

Cancer is a leading cause of human mortality. Given that it is difficult for conventional therapeutic approaches to effectively eradicate tumors and inhibit their recurrence and metastasis, new therapeutic strategies for solving this problem are urgently needed. In this work, we report the development of a two-dimensional titanium carbide nanocomposite drug delivery system. The system can be used for the synergistic treatment of tumors through photothermal/photodynamic/chemotherapy and can also inhibit tumor recurrence and metastasis by activating the immune system. A surface modification engineering strategy has been elaborately designed to realize the multifunctionalization of an MXene, Ti3C2. In this strategy, the nanocomposite drug delivery system (Ti3C2@Met@CP) was established via layer by layer adsorption of metformin (Met) and compound polysaccharide (CP) on the surface of Ti3C2 nanosheets. Among these materials, the synthesized (AlOH)4--functionalized Ti3C2 nanosheets possess strong near-infrared absorption (extinction coefficient of 36.2 L g-1 cm-1), high photothermal conversion efficiency (∼59.6%) and effective singlet oxygen generation (1O2). Compound polysaccharide (CP) is a new immunomodulator formed by mixing lentinan, pachymaran and tremella polysaccharides in optimal proportions. Especially, the decoration of CP onto the Ti3C2 nanosheets endows Ti3C2 with a well-defined shell, improves its tumor site aggregation and biocompatibility, and activates the host's immune functions. The synergistic eradication and inhibition of tumor recurrence and metastasis have been systematically evaluated by in vivo and in vitro experiments.

The COVID-19 pandemic continues to have a devastating effect on the health and well-being of the global population. A vital step in the combat towards COVID-19 is a successful screening of contaminated patients, with one of the key screening approaches being radiological imaging using chest radiography. This study aimed to automatically detect COVID‐19 pneumonia patients using digital chest x‐ray images while maximizing the accuracy in detection using deep convolutional neural networks (DCNN). The dataset consists of 864 COVID‐19, 1345 viral pneumonia and 1341 normal chest x‐ray images. In this study, DCNN based model Inception V3 with transfer learning have been proposed for the detection of coronavirus pneumonia infected patients using chest X-ray radiographs and achieved more than 96% accuracy. The results demonstrate that transfer learning proved to be effective, showed robust performance and easily deployable approach for COVID-19 detection.

Converging evidence from laboratory models pointed that the widely used antidiabetic drug metformin has direct effects on cancer cells. Thus far, relatively little attention has been addressed to the drug exposures used experimentally relative to those achievable clinically. Here, we demonstrated that metformin loaded on carbon nanotubes under near-infrared (NIR) irradiation led to the remarkably enhancement in response towards cancer cells. The dose of metformin has reduced to only 1/280 of typical doses in monotherapy (35: 10 000–30 000 µM) where the realization of metformin in conventional antidiabetic doses for cancer therapies becomes possible. The heat generated from carbon nanotubes upon NIR irradiation has mediated a strong and highly localized hyperthermia-like condition that facilitated the enhancement. Our work highlight the promise of using highly localized heating from carbon nanotubes to intensify the efficacy of metformin for potential cancer therapies.

The formation of a bead-shaped microstructure of poly{[3-octylthiophene-2,5-diyl]-[p-amino-azobenzylidenequinomethane]}bonded SWNT (PDTAABQ-SWNT) reveals the inhomogeneous distribution of reactive sites along a SWNT in a covalent functionalization. The bead-shaped microstructure arises from the twisting and entangling of polymer chains due to spatial confinement and geometrical restriction, as a result of dense functionalization into island-like small areas containing a high density of carboxyl groups on the SWNT sidewall. Accordingly a portion of ( Ca. 24.14%) trans -azobenzene side groups of PDTAABQ are forced to isomerize to the cis form due to a steric effect arising from the overcrowded environment in the ‘bead’. The experimental findings are well-correlated with the molecular simulation, particularly for the physical realization of a bead-shaped microstructure and a trans-cis isomerization. The distortion in morphology due to the inhomogeneous distribution of reactive sites leads to a method for controlling the electronic structure and photophysical properties of SWNT. The transient optical properties of PDTAABQ-SWNT show a faster decaying component on a picosecond timescale but a very unusual slower decaying tail on a nanosecond timescale as compared to the timescale of the parent polymer (PDTADBQ). The severely distorted polymer chains with cis azobenezene side groups result in the reduction of the exciton mobility, leading to the longer fluorescence lifetime. This is confirmed by a similar ratio of the undepleted photoexcitons after 2.2 ns ( Ca. 23.28%) and the ratio of the severely distorted polymers ( Ca . 24.14%).

This paper introduces a cheap simple MWCNTs@paper biosensor for the detection of CA19-9, which is a biomarker of pancreatic cancer. By adding the CA19-9 antibody to the surface of MWCNTs which are deposited on the microporous filter paper, the correlation between the concentration of CA19-9 and resistance of biosensor element was linear due to the site-specific binding of antigen and antibody. The detection range is wide (0 U/mL–at least 1000 U/mL), and even in the low concentration of CA19-9, the linearity remains satisfying. Based on this property, it could be used for the detection of early-stage pancreatic cancer. Besides, this research originally introduces a vacuum freeze-drying method for the long-term preservation of biosensor, prolonging its storage time from 3 h to at least 7 days, which signifcantly promoted its value in practical application. One piece of the MWCNTs@paper biosensor only cost $2 (about 30 times cheaper than ELISA) approximately, and the detection speed is satisfying (2 h, 12 times faster than ELISA), which will possibly increase its opportunity of mass production and clinical practice.

We investigate the phase control of six-wave mixing (SWM) in atomic system with multi-Zeeman levels theoretically and experimentally. With the relative phase varying, the switch between bright and dark state can appear in probe transmission signal. Then we demonstrate the evolution of six-wave mixing generated in bright and dark states by scanning the frequency detuning of the dressing field at different polarized probe field. Meanwhile, by utilizing the strong dressing effect of circular polarized light, we observe pure dark state switched to pure bright state in terms of energy level splitting, and compare different phases under different detuning of circularly polarized light. Theoretical calculations are in well agreement with the experimental observations.

We investigate the optical nonreciprocity induced by the parametrical amplification and the radiation trapping in an atomic photonic bandgap system both theoretically and experimentally. We use two pumping fields to generate entangled photon pairs from spontaneous parametric four-wave mixing, as well as the signals in which they can be enhanced by the feedback dressing effect. Therefore, the frequency difference and the shape change due to this feedback dressing on the two-arm ramps of one round trip are observed. Such optical nonreciprocity can be easily controlled by multiple experimental parameters (frequency detuning, power, and phase) of the dressing beams. In addition, the enhancement and suppression switching induced by the double dressing or triple dressing conditions are also studied. This optical nonreciprocity can contribute to the development of quantum information processing and quantum communications.

A lentinan (LEN) functionalized multi-walled carbon nanotubes (MWCNTs) drug delivery system, using tamoxifen (TAM) as a model anticancer agent, was developed by a simple non-covalent approach. This developed system (MWCNTs-TAM-LEN) possessed good stability, water dispersibility and extraordinary photothermal properties. It was demonstrated by the in vitro experiments that MWCNTs-TAM-LEN had enhanced cellular uptake, antitumor activity and cell apoptosis on Mcf-7 cells in comparison with TAM and MWCNTs-TAM. The cell inhibition rate and apoptosis rate of Mcf-7 cells treated by MWCNTs-TAM-LEN with near-infrared (NIR) were 67.1% and 66.5% higher than that of equivalent concentration of TAM with NIR irradiation treatment, respectively. The enhanced antitumor efficacy of MWCNTs-TAM-LEN was realized via the synergistic function of chemotherapy and photothermal ablation under NIR laser irradiation.

Ping Zhang,1,2 Wenhui Yi,1,2 Jin Hou,3 Sweejiang Yoo,1,2 Weiqiu Jin,1,2 Qisheng Yang1,2 1Key Laboratory for Physical Electronics and Devices of the Ministry of Education, School of Information and Electronics Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China; 2Key Laboratory for Information Photonic Technology of Shaanxi Province, School of Information and Electronics Engineering, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China; 3Department of Pharmacology, School of Basic Medical Sciences, Xi’an Medical University, Xi’an, Shaanxi, People’s Republic of China Purpose: Gemcitabine’s clinical application is limited due to its short plasma half-life and poor uptake by cells. To address this problem, a drug delivery three-component composite, multiwalled carbon nanotubes (MWNTs)/gemcitabine (Ge)/lentinan (Le; MWNTs-Ge-Le), was fabricated in our study. Moreover, the combination of chemotherapy and photothermal therapy was employed to enhance antitumor efficacy. Methods: In this study, we conjugated gemcitabine and lentinan with MWNTs via a covalent and noncovalent way to functionalize with MWNTs, and the chemical structure of MWNTs-Ge-Le was characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis and transmission electron microscopy. Using the composite and an 808nm laser, we treated tumors, both in vitro and in vivo, and investigated the photothermal responses and the anticancer efficacy. Results: The MWNTs-Ge-Le composite could efficiently cross cell membrane, having a higher antitumor activity than MWNTs, gemcitabine and MWNTs-Ge in vitro and in vivo. Our study on the MWNTs-Ge-Le composite with an 808nm laser radiation showed the combination of drug therapy and near-infrared photothermal therapy possesses great synergistic antitumor efficacy. Conclusion: The MWNTs-Ge-Le three-component anticancer composite can serve as a promising candidate for cancer therapy in the combination of chemotherapy and photothermal therapy. Keywords: drug-containing nanocomposites, characterization, near-infrared radiation, cancer therapy