Graphitic carbon nitride quantum dots(CNQDs) are emerging as attractive photoluminescent(PL)materials with excellent application potential in fluorescence imaging and heavy-metal ion detection. However, three limitati...Graphitic carbon nitride quantum dots(CNQDs) are emerging as attractive photoluminescent(PL)materials with excellent application potential in fluorescence imaging and heavy-metal ion detection. However, three limitations, namely, low quantum yields(QYs), self-quenching,and excitation-dependent PL emission behaviors, severely impede the commercial applications of crystalline CNQDs.Here we address these three challenges by synthesizing borondoped amorphous CNQDs via a hydrothermal process followed by the top±down cutting approach. Structural disorder endows the amorphous boron-doped CNQDs(B-CNQDs)with superior elastic strain performance over a wide range of pH values, thus effectively promoting mass transport and reducing exciton quenching. Boron as a dopant could fine-tune the electronic structure and emission properties of the PL material to achieve excitation-independent emission via the formation of uniform boron states. As a result, the amorphous B-CNQDs show unprecedented fluorescent stability(i.e., no obvious fading after two years) and a high QY of 87.4%;these values indicate that the quantum dots obtained are very promising fluorescent materials. Moreover, the B-CNQDs show bright-blue fluorescence under ultraviolet excitation when applied as ink on commercially available paper and are capable of the selective and sensitive detection of Fe^(2+) and Cd^(2+) in the parts-per-billion range. This work presents a novel avenue and scientific insights on amorphous carbon-based fluorescent materials for photoelectrical devices and sensors.展开更多
Combination therapy is a promising cancer treatment strategy that is usually based on the utilization of complicated nanostructures with multiple components functioning as photo-thermal energy transducers, photo-sensi...Combination therapy is a promising cancer treatment strategy that is usually based on the utilization of complicated nanostructures with multiple components functioning as photo-thermal energy transducers, photo-sensitizers, or dose intensifiers for phototherma! therapy （PTT）, photodynamic therapy （PDT）, or radiation therapy （RT）. In this study, ultrathin tungsten oxide nanowires （W18O49） were synthesized using a solvothermal approach and examined as a multifunctional theranostic nanoplatform. In vitro and in vivo analyses demonstrated that these nanowires could induce extensive heat- and singlet oxygen-mediated damage to cancer cells under 980 nm near infrared （NIR）-laser excitation. They were also shown to function as radiation dose intensifying agents that enhance irradiative energy deposition locally and selectively during radiation therapy. Compared to NIR-induced PTT/PDT and RT alone, W18O49 - based synergistic tri-modal therapy eradicated xenograft tumors and no recurrence was observed within a 9-month follow up. Moreover, the strong X-ray attenuation ability of the tungsten element （Z = 74, 4.438 cm^2·g^-1, 100 KeV） qualified these nanowires as excellent contrast agents in X-ray-based imaging, such as diagnostic computed tomography （CT） and cone-beam CT for image-guided radiation therapy. Toxicity studies demonstrated minimal adverse effects on the hematologic system and major organs of mice within one month. In conclusion, these nanowires have shown significant potential for cancer therapy with inherent image guidance and synergistic effects from phototherapy and radiation therapy, which warrants further investigation.展开更多
基金supported by the National Natural Science Foundation of China (51772085 and 12072110)the Natural Science Foundation of Hunan Province (2020JJ4190)。
文摘Graphitic carbon nitride quantum dots(CNQDs) are emerging as attractive photoluminescent(PL)materials with excellent application potential in fluorescence imaging and heavy-metal ion detection. However, three limitations, namely, low quantum yields(QYs), self-quenching,and excitation-dependent PL emission behaviors, severely impede the commercial applications of crystalline CNQDs.Here we address these three challenges by synthesizing borondoped amorphous CNQDs via a hydrothermal process followed by the top±down cutting approach. Structural disorder endows the amorphous boron-doped CNQDs(B-CNQDs)with superior elastic strain performance over a wide range of pH values, thus effectively promoting mass transport and reducing exciton quenching. Boron as a dopant could fine-tune the electronic structure and emission properties of the PL material to achieve excitation-independent emission via the formation of uniform boron states. As a result, the amorphous B-CNQDs show unprecedented fluorescent stability(i.e., no obvious fading after two years) and a high QY of 87.4%;these values indicate that the quantum dots obtained are very promising fluorescent materials. Moreover, the B-CNQDs show bright-blue fluorescence under ultraviolet excitation when applied as ink on commercially available paper and are capable of the selective and sensitive detection of Fe^(2+) and Cd^(2+) in the parts-per-billion range. This work presents a novel avenue and scientific insights on amorphous carbon-based fluorescent materials for photoelectrical devices and sensors.
基金Acknowledgements This work has been financially supported by the National Natural Science Foundation of China （Nos. 51372260, 51132009, and 21172043）, the Shanghai Rising-Star Program （No. 12QH1402500）, the Science and Technology Commission of Shanghai （No. 11nm0505000 and 124119a0400）, the Shanghai Municipal Commission of Health （No. 20134360）, the Development Foundation for Talents of Shanghai （No. 2012035）.
文摘Combination therapy is a promising cancer treatment strategy that is usually based on the utilization of complicated nanostructures with multiple components functioning as photo-thermal energy transducers, photo-sensitizers, or dose intensifiers for phototherma! therapy （PTT）, photodynamic therapy （PDT）, or radiation therapy （RT）. In this study, ultrathin tungsten oxide nanowires （W18O49） were synthesized using a solvothermal approach and examined as a multifunctional theranostic nanoplatform. In vitro and in vivo analyses demonstrated that these nanowires could induce extensive heat- and singlet oxygen-mediated damage to cancer cells under 980 nm near infrared （NIR）-laser excitation. They were also shown to function as radiation dose intensifying agents that enhance irradiative energy deposition locally and selectively during radiation therapy. Compared to NIR-induced PTT/PDT and RT alone, W18O49 - based synergistic tri-modal therapy eradicated xenograft tumors and no recurrence was observed within a 9-month follow up. Moreover, the strong X-ray attenuation ability of the tungsten element （Z = 74, 4.438 cm^2·g^-1, 100 KeV） qualified these nanowires as excellent contrast agents in X-ray-based imaging, such as diagnostic computed tomography （CT） and cone-beam CT for image-guided radiation therapy. Toxicity studies demonstrated minimal adverse effects on the hematologic system and major organs of mice within one month. In conclusion, these nanowires have shown significant potential for cancer therapy with inherent image guidance and synergistic effects from phototherapy and radiation therapy, which warrants further investigation.
