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Biofilm-associated dental diseases and tooth discoloration have recently become the major barriers to achieve healthy teeth. However, there are few effective strategies to address these issues. Herein, the piezo-photocatalytic process is first proposed to be applied for biofilm eradication and tooth whitening with well-designed direct Z scheme g-C3N4−x/Bi2O3−y heterostructures. DFT calculation and XPS results verify the formation of direct Z scheme g-C3N4/Bi2O3 heterostructures theoretically and experimentally. Using the direct Z scheme g-C3N4−x/Bi2O3−y heterostructure, excellent piezo-photocatalytic effects for tooth whitening and biofilm removal are achieved. For piezo-photocatalytic degradation of the typical food colorant of indigo carmine the degradation rate constant is about quadruple that of piezocatalytic and 2.6 times of photocatalytic treatment. Tooth whitening experiments indicate that g-C3N4−x/Bi2O3−y could whiten the stained teeth through the synergistic piezo-photocatalysis. In addition, excellent antibacterial performances can be obtained on the g-C3N4−x/Bi2O3−y heterostructure through piezo-photocatalytic treatment. Not only the planktonic S. mutans but also those bacteria embedded in biofilms can be effectively killed. The analyses of the piezo-photocatalytic mechanism indicates that the enhanced piezo-photocatalytic performance of the g-C3N4−x/Bi2O3−y heterostructure could be attributed to the much higher separation efficiency of photoexcited charge carriers, increased production amounts of ROS and superior adsorption ability for bacteria than those with bare semiconductors of g-C3N4−x and Bi2O3−y and those treated only with ultrasonic vibration or irradiation. Biosafety results show that the g-C3N4−x/Bi2O3−y heterostructure is biologically safe and piezo-photocatalytic treatment has no harm the tooth structure, demonstrating the great potential of piezo-photocatalytic effect based new tooth whitening and antibacterial technology in future dental care fields. [ABSTRACT FROM AUTHOR]

Theranostics that combines the disease diagnosis with treatment is of promising application in the foreground of personalized medicine to achieve a precise treatment with minimum side effects. In this work, we strategically designed a “four-in-one” theranostic nanoplatform for realizing the desired imaging-guided phototherapy, in which functions of fluorescent imaging, photoacoustic imaging tomography (PAT), photothermal therapy (PTT) and photodynamic therapy (PDT) were implemented by bioconjugated MoS2 nanosheets. The protagonist of MoS2 is a light-harvesting material in the near-infrared (NIR) region, which would produce localized hyperthermia at the tumor site to trigger the photothermal therapy effect for the tumor ablation as well as a PAT signal to depict the tumor concurrently upon NIR excitation. To our surprise, MoS2 has been found to be a photosensitizer for the cancer PDT treatment as well. Moreover, bovine serum albumin (BSA) decoration on MoS2 has been made to improve biocompatibility, which also allowed further conjugation with a fluorescent molecule of Cy5.5 to endow the overall nanoplatform with fluorescence imaging and monitoring features. On the basis of the above characters, great successes in cancer imaging and tumor photoablation were achieved in both in vitro and in vivo experiments. Innovatively, B-ultrasonography and MRI imaging were employed to monitor the elimination process of solid tumor after treatment, which clearly revealed a liquefaction necrosis process for rehabilitation. In short, MoS2 represents a nanoplatform of this work and manifested huge advantages in the cancer theranostics. [ABSTRACT FROM AUTHOR]

An electrochemiluminescence (ECL) immunosensor for HepG2 cells (human liver hepatocellular carcinoma cells) was fabricated based on CdS-capped TiO2 hybrid nanoparticles. The CdS-capped TiO2 was obtained by immersing TiO2 nanoparticles into separate Cd2+ and S2− solutions successively 10 times. The hybrid nanoparticles have excellent ECL intensity after coating with 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid (IL) and 3-aminopropyl-triethoxysilane (APTES). The viscous IL is helpful to immobilize the hybrid nanoparticles on the electrode as well as for the electron transfer from nanoparticles to the electrode, which is advantageous to the ECL immunosensor. APTES was used to attach gold nanoparticles onto the electrode surface. The HepG2 antibodies were then immobilized onto the electrode surface via the interaction between their amine groups and gold nanoparticles. A wide detection range from 400 to 10 000 cells per mL was achieved. The detection limit was determined to be 396 cells per mL. Using HeLa cells as interferences, the excellent selectivity of this sensor has been demonstrated using both confocal fluorescence microscopy and ECL techniques. Due to its good sensitivity, selectivity and stability, the sensor has great potential in medical diagnosis. [ABSTRACT FROM AUTHOR]

Biofilm-associated dental diseases and tooth discoloration have recently become the major barriers to achieve healthy teeth. However, there are few effective strategies to address these issues. Herein, the piezo-photocatalytic process is first proposed to be applied for biofilm eradication and tooth whitening with well-designed direct Z scheme g-C 3 N 4- x /Bi 2 O 3- y heterostructures. DFT calculation and XPS results verify the formation of direct Z scheme g-C 3 N 4 /Bi 2 O 3 heterostructures theoretically and experimentally. Using the direct Z scheme g-C 3 N 4- x /Bi 2 O 3- y heterostructure, excellent piezo-photocatalytic effects for tooth whitening and biofilm removal are achieved. For piezo-photocatalytic degradation of the typical food colorant of indigo carmine the degradation rate constant is about quadruple that of piezocatalytic and 2.6 times of photocatalytic treatment. Tooth whitening experiments indicate that g-C 3 N 4- x /Bi 2 O 3- y could whiten the stained teeth through the synergistic piezo-photocatalysis. In addition, excellent antibacterial performances can be obtained on the g-C 3 N 4- x /Bi 2 O 3- y heterostructure through piezo-photocatalytic treatment. Not only the planktonic S. mutans but also those bacteria embedded in biofilms can be effectively killed. The analyses of the piezo-photocatalytic mechanism indicates that the enhanced piezo-photocatalytic performance of the g-C 3 N 4- x /Bi 2 O 3- y heterostructure could be attributed to the much higher separation efficiency of photoexcited charge carriers, increased production amounts of ROS and superior adsorption ability for bacteria than those with bare semiconductors of g-C 3 N 4- x and Bi 2 O 3- y and those treated only with ultrasonic vibration or irradiation. Biosafety results show that the g-C 3 N 4- x /Bi 2 O 3- y heterostructure is biologically safe and piezo-photocatalytic treatment has no harm the tooth structure, demonstrating the great potential of piezo-photocatalytic effect based new tooth whitening and antibacterial technology in future dental care fields.

Theranostics that combines the disease diagnosis with treatment is of promising application in the foreground of personalized medicine to achieve a precise treatment with minimum side effects. In this work, we strategically designed a "four-in-one" theranostic nanoplatform for realizing the desired imaging-guided phototherapy, in which functions of fluorescent imaging, photoacoustic imaging tomography (PAT), photothermal therapy (PTT) and photodynamic therapy (PDT) were implemented by bioconjugated MoS 2 nanosheets. The protagonist of MoS 2 is a light-harvesting material in the near-infrared (NIR) region, which would produce localized hyperthermia at the tumor site to trigger the photothermal therapy effect for the tumor ablation as well as a PAT signal to depict the tumor concurrently upon NIR excitation. To our surprise, MoS 2 has been found to be a photosensitizer for the cancer PDT treatment as well. Moreover, bovine serum albumin (BSA) decoration on MoS 2 has been made to improve biocompatibility, which also allowed further conjugation with a fluorescent molecule of Cy5.5 to endow the overall nanoplatform with fluorescence imaging and monitoring features. On the basis of the above characters, great successes in cancer imaging and tumor photoablation were achieved in both in vitro and in vivo experiments. Innovatively, B-ultrasonography and MRI imaging were employed to monitor the elimination process of solid tumor after treatment, which clearly revealed a liquefaction necrosis process for rehabilitation. In short, MoS 2 represents a nanoplatform of this work and manifested huge advantages in the cancer theranostics.

An electrochemiluminescence (ECL) immunosensor for HepG2 cells (human liver hepatocellular carcinoma cells) was fabricated based on CdS-capped TiO 2 hybrid nanoparticles. The CdS-capped TiO 2 was obtained by immersing TiO 2 nanoparticles into separate Cd 2+ and S 2- solutions successively 10 times. The hybrid nanoparticles have excellent ECL intensity after coating with 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid (IL) and 3-aminopropyl-triethoxysilane (APTES). The viscous IL is helpful to immobilize the hybrid nanoparticles on the electrode as well as for the electron transfer from nanoparticles to the electrode, which is advantageous to the ECL immunosensor. APTES was used to attach gold nanoparticles onto the electrode surface. The HepG2 antibodies were then immobilized onto the electrode surface via the interaction between their amine groups and gold nanoparticles. A wide detection range from 400 to 10 000 cells per mL was achieved. The detection limit was determined to be 396 cells per mL. Using HeLa cells as interferences, the excellent selectivity of this sensor has been demonstrated using both confocal fluorescence microscopy and ECL techniques. Due to its good sensitivity, selectivity and stability, the sensor has great potential in medical diagnosis.