Search

Carbon dot-based room temperature phosphorescence materials are reported, mainly focusing on the outstanding contributions over the years, phosphorescence emission, phosphorescence lifetime, preparation and application.

Luminescent solar concentrators (LSCs) are able to collect sunlight from a large-area to generate electric power with a low cost, showing great potential in building-integrated photovoltaics. However, the low efficiency of large-area LSCs caused by the reabsorption losses is a critical issue that hampers their practical applications. In this work, we synthesized novel yellow emissive carbon dots (CDs) with a large Stokes shift of 193 nm, which exhibit nearly zero reabsorption. The quantum yield (QY) of the yellow emitting CDs is up to 61%. The yellow emitting CDs can be employed to fabricate high-performance large-area LSCs due to successful suppression of the reabsorption losses. The as-prepared LSCs are able to absorb 14% of the sunlight as the absorption of the CDs matches well with the sun's spectrum. The large-area LSC (10 × 10 cm

Background: Lung cancer is one of the leading causes of cancer-related deaths worldwide. Platycodin D (PD), a major pharmacological constituent from the Chinese medicinal herb named Platycodonis Radix, has shown potent anti-tumor activity. Also, it is reported that PD could inhibit cellular growth in the non-small-cell lung carcinoma (NSCLC) A549 cell line. However, the underlying mechanism is not fully clarified. Methods: Cell proliferation was measured by MTT assay. Annexin V and propidium iodide (PI) assay were employed to study the apoptosis effects of PD on A549 cells. Western blot analysis was used to evaluate protein expression. Also, we used a siRNA against p53, as well as a plasmid-based RRM1 over-expression to investigate their functions. Results: It is demonstrated that PD inhibited A549 cell proliferation in a dose- and time-dependent manner. Further investigations showed that PD induced cell apoptosis, which was supported by dose-dependent and time-dependent caspase-3 activation and p53/VEGF/MMP2 pathway regulation. Also, PD demonstrated the inhibition effect of ribonucleotide reductase M1 (RRM1), whose role in various tumors is contradictory. Remarkably, in this work, RRM1 overexpression in A549 cells could have a negative impact on the regulation of the p53/VEGF/MMP2 pathway induced by PD treatment. Note that RRM1 overexpression also attenuated cell apoptosis and inhibition of cell proliferation of A549 treated with PD. Conclusion: The results suggested that PD could inhibit A549 cell proliferation and induce cell apoptosis by regulating p53/VEGF/MMP2 pathway, in which RRM1 plays an important role directly.

As a relatively new type of fluorescent carbon-based nanomaterials, multicolor carbon dots (MCDs) have attracted much attention because of their excellent biocompatibility, tunable photoluminescence (PL), high quantum yield, and unique electronic and physicochemical properties. The multicolor emission characteristics of carbon dots (CDs) obviously depend on the carbon source precursor, reaction conditions, and reaction environment, which directly or indirectly determines the multicolor emission characteristics of CDs. Therefore, this review is the first systematic classification and summary of multiple regulation methods of synthetic MCDs and reviews the recent research progress in the synthesis of MCDs from a variety of precursor materials such as aromatic molecules, small organic molecules, and natural biomass, focusing on how different regulation methods produce corresponding MCDs. This review also introduces the innovative applications of MCDs in the fields of biological imaging, light-emitting diodes (LEDs), sensing, and anti-counterfeiting due to their excellent PL properties. It is hoped that by selecting appropriate adjustment methods, this review can inspire and guide the future research on the design of tailored MCDs, and provide corresponding help for the development of multifunctional MCDs.

Carbon dots (CDs) have been widely used in biomedical fields because of their superior optical properties, high sensitivity and high selectivity to specific substances. However, there are few studies on trace detection of the ethanol content in aqueous solution using CDs. Herein, novel red fluorescent CDs with dual emission are synthesized and show good dispersibility in various solvents and excitation independence of photoluminescence (PL). After investigating the structure and properties of the red CDs, a multifunctional fluorescent nanoprobe based on the red CDs with high-sensitivity detection for dual-ion trace detection of Fe

BACKGROUND: Specific alterations in human leukocyte antigen class I (HLA-I) loci are associated with clinical outcomes for immune checkpoint inhibitors, which increase the clinical relevance of accurate high-resolution HLA genotyping in immuno-oncology applications. Numerous algorithms have been developed for high- to full-resolution HLA genotyping by next-generation sequencing (NGS) data; however, Sanger sequencing-based typing (SBT) remains the gold standard. With the increasing use of NGS for clinical oncology, it is important to identify the computational tool with comparable performance as the gold standard. This study aimed to benchmark 5 algorithms against SBT for the high-resolution typing of classical HLA-I genes for targeted NGS data from blood and tissue samples. METHODS: Paired white blood cell (WBC), plasma, and tissue deoxyribonucleic acid (DNA) samples derived from 22 cancer patients with known HLA genotypes were sequenced using a panel of all the following exons of classical HLA-I genes: HLA-A, HLA-B, and HLA-C. NGS-based genotypes were generated by the 5 different algorithms, including HLA-HD, HLAscan, OptiType, Polysolver, and xHLA. Accuracy was defined as the concordance between the SBT and NGS-based algorithms. Accuracy was computed as the fraction of all the alleles with concordant genotype using the SBT and any of the algorithm over the total number of alleles. RESULTS: In relation to the WBC, plasma, and tissue samples, all 5 algorithms were highly accurate at low-resolution HLA-I genotyping, but had more varied accuracy at high-resolution HLA-I genotyping, particularly in HLA-A. The in-silico analyses revealed that high-resolution genotyping by all 5 algorithms achieved approximately 90% accuracy at sequencing depths of 6,000× – 100× for the WBC samples, at 6,000× – 700× for the plasma samples, and at 1,000× – 100× for the tissue samples. Among the 5 algorithms, HLA-HD was consistently accurate at high-resolution HLA-I genotyping, and had an accuracy of 93.9% for the WBC samples, 87.9% for the plasma samples, and 94.2% for tissue samples even at a 50× sequencing depth. CONCLUSIONS: We found that HLA-HD was an accurate algorithm for the high-resolution genotyping of classical HLA-I genes sequenced by our targeted panel, particularly at a sequencing depth ≥300× for blood and tissue samples.

Luminescent solar concentrators (LSCs) can collect solar light from a large area and concentrate it on their small-area edges mounted with solar cells for efficient solar-to-electricity conversion. Thus, LSCs show huge promise for realizing building-integrated photovoltaics because of their semi-transparency and light weight. However, the low optical efficiency of LSCs becomes a great obstacle for their application in real energy conversion. Herein, yellow emissive carbon dots with a record-breaking ultrahigh quantum yield of up to 86.4% were prepared via a simple hydrothermal approach using low-cost precursors. By combining them with red emissive carbon dots (quantum yield of 17.6%), a large area (∼100 cm2) tandem LSC was fabricated. The power conversion efficiency (PCE) of the large-area carbon dot-integrated tandem LSC reaches up to 3.8%, which is among the best reported in literature for a similar lateral size of LSCs. In particular, the tandem structure based on two laminated layers is novel, and is fit for the real structural application of keeping windows warm, where two glass slides are usually used. The high-efficiency tandem LSC using eco-friendly carbon dots as fluorophores paves way for real applications of LSCs.

It is known that mammalian target of rapamycin (mTOR) signaling plays an important role in NSCLC cells proliferation. Torin2 is a second-generation ATP-competitive inhibitor which is selective for mTOR activity. In this study, we investigated whether torin2 was effective against lung cancer cells, especially EGFR-TKIs resistant NSCLC cells. We found that torin2 dramatically inhibited EGFR-TKI resistant cells viability in vitro. In xenograft model, torin2 treatment significantly reduced the volume and weight of xenograft tumor in the erlotinib resistant PC9/E cells. Additionally, autophagy protein of phosphatidylethanolamine-modified microtubule-associated protein light-chain 3II/I (LC3II/I) increased in PC9/E after torin2 treatment. Torin2 blocked the level of phosphorylated S6 and the phosphorylation of Akt at both T308 and S473 sites compared with erlotinib treatment. Furthermore, TUNEL assay showed that apoptosis of tumor tissue increased significantly in the torin2 treatment group. Immunohistochemical analysis demonstrated that tumor angiogenesis was obviously inhibited by torin2 treatment in EGFR-TKI resistant group. Collectively, our results suggested that torin2 could inhibit the NSCLC cells proliferation by negative feedback regulation of Akt/mTOR signaling and inducing autophagy. This suggests that torin2 could be a novel therapeutic approach for EGFR-TKI resistant NSCLC.

Aiping Ma,1,* Lifang Wen,2,* Junping Yin,3 Yi Hu,4 Xiaoyang Yue,3 Jiurong Li,1 Xiaoru Dong,2 Yask Gupta,5 Ralf J Ludwig,5 Susanne Krauss-Etschmann,3,6 Gabriela Riemekasten,7 Frank Petersen,3 Xinhua Yu2,3 1Department of Respiratory Medicine, The First Affiliated Hospital, School of Medicine, Xiamen University, Xiamen, People’s Republic of China; 2Xiamen-Borstel Joint Laboratory of Autoimmunity, The Medical College of Xiamen University; 3Priority Area Asthma and Allergy, Research Center Borstel, Airway Research Center North (ARCN), Members of the German Center for Lung Research (DZL), Borstel, Germany; 4Department of Clinical Laboratory, The First Affiliated Hospital, School of Medicine, Xiamen University, Xiamen, People’s Republic of China; 5Lübeck Institute of Experimental Dermatology, University of Lübeck, Lübeck, Germany; 6Institute for Experimental Medicine, Christian-Albrechts-Universitaetzu Kiel, Kiel, Germany; 7Department of Rheumatology, University of Lübeck, Lübeck 23538, Germany*These authors contributed equally to this workCorrespondence: Xinhua YuPriority Area Asthma and Allergy, Research Center Borstel, Borstel 23845, GermanyTel +49 453 7188 2520Email xinhuayu@fz-borstel.deBackground: Chronic obstructive pulmonary disease (COPD) is a highly prevalent disease leading to irreversible airflow limitation and is characterized by chronic pulmonary inflammation, obstructive bronchiolitis and emphysema. Etiologically, COPD is mediated by toxic gases and particles, eg, cigarette smoke, while the pathogenesis of the disease is largely unknown. Several lines of evidence indicate a link between COPD and autoimmunity but comprehensive studies are lacking.Methods: By using a protein microarray assaying more than 19,000 human proteins we determined in this study the autoantibody profiles of COPD and non-COPD smokers. The discovery cohort included 5 COPD patients under acute exacerbation (AECOPD) and 5 age- and gender-matched non-COPD smokers. One putative candidate autoantibody, anti-lactoferrin IgG, was further investigated by using immunoblotting with a large validation cohort containing 124 healthy controls, 92 patients with AECOPD and 52 patients with stable COPD.Results: We show that i) autoantigens targeted by autoantibodies with higher titers in COPD patients were enriched in extracellular regions, while those with lower titers in COPD patients were enriched in intracellular compartments. ii) levels of IgG autoantibodies against many neutrophil granule proteins were significantly higher in COPD patients than in non-COPD smokers. Furthermore, increased levels of anti-lactoferrin antibodies in COPD patients were confirmed in a cohort with a large number of samples.Conclusion: The comprehensive autoantibody profiles from COPD patients established in this study demonstrated for the first time a shift in the cellular localization of antigens targeted by autoantibodies in COPD.Keywords: chronic obstructive pulmonary disease, autoimmunity, autoantibody profile, neutrophil granule proteins, lactoferrin

Lattice phosphorus (P) doping has been demonstrated as an effective method for tuning the fluorescence of graphene quantum dots (GQDs). Due to the many possible oxidation states of P, lattice P-doped GQDs (P-GQDs) are still difficult to synthesize. Here, we report the green preparation of P-GQDs via solvothermal treatment of lecithin with high yield (71 wt%). The resulting P-GQDs show controllable emission wavelength (457–632 nm) and high quantum yield (0.54–0.73), and have demonstrated potential for applications in fluorescent bio-imaging.

Direct integration of monolayer graphene on a silicon (Si) substrate is realized by a simple thermal annealing process, involving a top copper (Cu) layer as the catalyst and an inserted polymethylmethacrylate (PMMA) as the carbon source. After spin-coating the PMMA carbon source on the Si substrate, the Cu catalyst was deposited on PMMA/Si by electron beam evaporation. After that, graphene was directly synthesized on Si by decomposition and dehydrogenation of PMMA and the catalyzation effect of Cu under a simple thermal annealing process. Furthermore, under an optimized growth condition, monolayer graphene directly formed on the Si substrate was demonstrated. Utilizing the as-grown graphene/Si heterojunction, near-infrared photodetectors with high detectivity (∼1.1 × 1010 cm Hz1/2 W−1) and high responsivity (50 mA W−1) at 1550 nm were directly fabricated without any post-transfer process. The proposed approach for directly growing graphene on silicon is highly scalable and compatible with present nano/micro-fabrication systems, thus promoting the application of graphene in microelectronic fields.

This paper sheds light on the effects of process parameters on the low-temperature growth of vertical graphene nano-petals (VGNPs) by plasma-assisted chemical vapor deposition (PACVD) at 550 °C without the presence of any catalyst or post-transfer treatment. The parameters include substrate temperature, plasma power and growth time. The significant influence of these variable parameters reveals the morphological evolution, growth rate and quality of VGNPs. Furthermore, the defect-guided growth mechanism of the VGNPs is discussed in detail. The as-grown VGNPs possess high hydrophobicity (water contact angle: 137°) due to their unique physicochemical properties, ultra-high specific surface area, exposed sharp edges and non-stacking three-dimensional geometry. This study provides a methodology for optimizing the conditions to prepare VGNPs. A gas sensor exhibits superior sensitivity due to high specific surface area and a parts-per-trillion (ppt) level of NH3 detection capabilities and is directly manufactured on a SiO2 substrate with VGNPs. Moreover, Joule-heating expels molecules by physisorption from the vertical surface leading to fully reversible and low-power operation. Our study may provide new insights into the improved design of graphene-based sensing applications.

BTK is an effective target for the treatment of B-cell malignant tumors and autoimmune diseases. In this work, a series of 2-phenyl pyrimidine derivatives were prepared and their preliminary in vitro activities on B-cell leukemia cells as well as the BTK enzyme were determined. The results showed that compound 11g displayed the best inhibitory activity on BTK with an inhibition rate of 82.76% at 100 nM and excellent anti-proliferation activity on three B-cell leukemia lines (IC(50) = 3.66 μM, 6.98 μM, and 5.39 μM against HL60, Raji and Ramos, respectively). Besides, the flow cytometry analysis results indicated that 11g inhibited the proliferation of the Raji cells in a dose- and time-dependent manner, and blocked the Ramos cells at the G0/G1 phase, which is in accordance with the positive control ibrutinib. The mechanism investigation demonstrated that 11g could inhibit the phosphorylation of BTK and its downstream substrate phospholipase γ2 (PLCγ2). All these results showed that 11g was a promising lead compound that merited further optimization as a novel class of BTK inhibitor for the treatment of B-cell lymphoblastic leukemia.

Graphene-based nanomaterials (GBNs) are known to exhibit biocidal activities, however, the combined effect of GBNs based on physical disruption and oxidative stress on different types of bacteria remain unclear. Here, we use both Gram-negative (Escherichia coli and Salmonella typhimurium) and Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) bacteria to investigate the antimicrobial properties of vertically and horizontally aligned graphenes grown on semiconductor silicon (Si) and insulator silicon dioxide (SiO2). It is found that the bacteria show different sensitivity to isomeric-structured GBNs. Gram-negative bacteria are more vulnerable to graphene-coated Si substrates than to SiO2, because the less negatively charged membrane enhances the electron transfer effect that extracts the electrons from the microbial membranes, and Gram-positive bacteria seem to show more susceptibility to physical puncturing of vertically aligned graphene than to horizontally aligned graphene due to the nature of the compound and the shape of the membrane structure. Subsequently, the vertically aligned graphene Si substrate (G@V-Si) exerts the superior antimicrobial ability on all the bacteria. Finally, all the above GBNs show low cytotoxicity and high biocompatibility, and the robust in vivo antibacterial effect indicates that G@V-Si could serve as an ideal platform for antimicrobial treatment.

Tunable photoluminescence performance of graphene quantum dots (GQDs) is one of the most important topics for the development of GQDs. In this paper, we report lattice-doped GQDs (boron-doped GQDs (B-GQDs) and phosphorus-doped GQDs (P-GQDs)). Because of the matched band structure, the fast energy transfer between blue-emitted B-GQDs (emission wavelength: 460 nm) and orange-emitted P-GQDs (emission wavelength: 630 nm) can induce an efficient fluorescence emission in P-GQDs once B-GQDs are excited under the optimal excitation wavelength of 460 nm. Moreover, with the effective energy transfer, the quantum yield of P-GQDs increased to 0.48, which is much higher than that of pure P-GQDs. We also demonstrated the potentials of this system for fluorescent bioimaging in vitro.

Graphene quantum dots have attracted the researchers' attention due to its high stability, low cost and controllable photoluminescence performance. In this paper, we report the synthesis of ethylenediamine functionalized graphene quantum dots (E-GQDs). The E-GQDs is synthesized via hydrothermal treatment of the mixed solution of graphene quantum dots and ethylenediamine. The E-GQDs shows remarkable quantum yield (0.83). The quantum yield of E-GQDs is higher than quantum yields of most previously reported GQDs. Moreover, due to the coordination between Ni2+ and ethylenediamine, the PL of E-GQDs quenched via static quenching process. This makes the E-GQDs an alternative for ultra-sensitive PL probe of Ni2+ (detection limit: 3 × 10−8 M) with high antijamming capability. We also demonstrated the good performance of E-GQDs in vitro detection of Ni2+.

The peculiar properties of the large absorption coefficient at near-infrared frequencies as well as their high mobility in germanium enable promising applications in photodetection. Schottky junctions based near-infrared photodetectors were fabricated by integrating monolayer graphene film with germanium membranes stacking on silicon oxide substrates (i.e., GeOI). The device exhibits a strong photovoltaic behavior, giving rise to high responsivity and detectivity of ∼62.1 mA W−1 and ∼2.1 × 1011 cm Hz1/2 W−1, respectively. Time-response results indicate that the device could operate with the frequency up to 1 kHz. Our work may pave the way for exploiting graphene/GeOI Schottky junctions as the high-performance optoelectronic devices.

Graphene that is directly integratable into electronic devices after its growth is highly desirable but is difficult to fabricate due to its relatively high growth temperatures (∼1000 °C) and inevitable transfer step. Herein, we propose a convenient and feasible strategy to directly synthesize high-quality polycrystalline graphene on Si substrates by utilizing plasma-assisted chemical vapor deposition (PACVD), where three main features inevitable to traditional growth methods, i.e., transition metals as catalysts, post-transfer process and high growth temperature, can be thoroughly circumvented. Notably, the growth temperature is significantly reduced and reaches as low as 700 °C. The utilized PACVD provides exceptional abilities of hydrocarbon pyrolysis and graphene formation even on unusual Si substrates. Furthermore, the as-grown graphene-on-Si (GOS) exhibits superior capabilities that can be used to directly fabricate high performance optoelectronic devices, e.g., photodetectors. Typical current rectification characteristics and good photovoltaic conversion efficiency are demonstrated in as-grown graphene/Si Schottky junctions.

To realize the potential of graphene in nanoelectronic devices, large area of graphene sheets with high quality are desirable. Here, we have proposed a new method to weld the reduced graphene oxide (rGO) together by efficient coupling reaction, leading to the lateral size increased. Both crystallinity and electrical conductivity of the welded rGO were significantly improved. Furthermore, the reaction mechanism is studied by Raman, TEM, XPS spectra, optical transmittance, and square resistance measurements. Our technique can product high-quality graphene for fabricating graphene devices.

In distinction to the generally utilized chemical vapor deposition (CVD) synthesis that leads to multilayer graphene growth by carbon (C) synthesis from nickel (Ni), we proposed a controllable strategy to synthesize graphene on an arbitrary substrate through ion implantation technology, where the layer number of the obtained graphene film is accurately controlled by the corresponding dose of implanted C ions. To be specific, an oxide layer (NiO) was introduced as the barrier to prevent implanted C atom precipitation at the surface but at the interface. Various unusual substrates (such as sapphire, glass, SiO2, and Si), in terms of traditional CVD, have been utilized for growing high-quality graphene. Employing the as-grown graphene/Si, Schottky junction-based photodetectors with high responsivity (63 mA W−1) and high detectivity (∼1.4 × 1010 cm Hz1/2 W−1) at 1550 nm are demonstrated without requiring any post-transfer process, thus avoiding additional contaminations, complexities, and costs during device fabrications. Our works afford a versatile technique for growing graphene on arbitrary substrates, with controllable layer numbers and transfer-free optoelectronic device fabrications, thus accelerating their further practical applications in electro-optical devices.

Hydrogenation-induced cracking in Si/B-doped Si0.70Ge0.30/Si heterostructure with ultralow dose hydrogen implantation (3 × 1016/cm2) is demonstrated. The thickness of the Si0.70Ge0.30 interlayer, embedded between a 240 nm thick Si capping layer and the Si substrate, is 15 nm. After hydrogen implantation, long range H migration and trapping occurred in the Si0.70Ge0.30 interlayer are observed. Moreover, the crack is found to be closely correlated to the concentration of B atoms doped in the buried Si0.70Ge0.30 layer. With increasing B concentrations, the trapped H increases, leading to a smooth cracking confined in the Si0.70Ge0.30/Si interface, and fewer defects are found in the Si capping layer. In conjunction with plasma activation and wafer bonding, the as-transferred Si-on-insulator possesses a rather smooth surface (0.24 nm) and low threading dislocation density (4.4 × 105 cm−2).Hydrogenation-induced cracking in Si/B-doped Si0.70Ge0.30/Si heterostructure with ultralow dose hydrogen implantation (3 × 1016/cm2) is demonstrated. The thickness of the Si0.70Ge0.30 interlayer, embedded between a 240 nm thick Si capping layer and the Si substrate, is 15 nm. After hydrogen implantation, long range H migration and trapping occurred in the Si0.70Ge0.30 interlayer are observed. Moreover, the crack is found to be closely correlated to the concentration of B atoms doped in the buried Si0.70Ge0.30 layer. With increasing B concentrations, the trapped H increases, leading to a smooth cracking confined in the Si0.70Ge0.30/Si interface, and fewer defects are found in the Si capping layer. In conjunction with plasma activation and wafer bonding, the as-transferred Si-on-insulator possesses a rather smooth surface (0.24 nm) and low threading dislocation density (4.4 × 105 cm−2).

Vertical few layered graphene (VG) nanoflakes were directly synthesized on traditional glass substrate by the plasma-assisted chemical vapor deposition, where the extremely low growing temperature (