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1.
Langmuir ; 40(15): 7843-7859, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38557084

RESUMO

Two-dimensional materials have shown immense promise for gas-sensing applications due to their remarkable surface-to-volume ratios and tunable chemical properties. However, despite their potential, the utilization of ReSe2 as a gas-sensing material for nitrogen-containing molecules, including NO2, NO, and NH3, has remained unexplored. The choice of doping atoms in ReSe2 plays a pivotal role in enhancing the gas adsorption and gas-sensing capabilities. Herein, the adsorption properties of nitrogen-containing gas molecules on metal and non-metal single-atom (Au, Pt, Ni, P, and S)-doped ReSe2 monolayers have been evaluated systematically via ab initio calculations based on density functional theory. The findings strongly suggest that intrinsic ReSe2 has better selectivity toward NO2 than toward NO and NH3. Moreover, our results provide compelling evidence that all of the dopants, with the exception of S, significantly enhance both the adsorption strength and charge transfer between ReSe2 and the investigated molecules. Notably, P-decorated ReSe2 showed the highest adsorption energy for NO2 and NO (-1.93 and -1.52 eV, respectively) with charge transfer above 0.5e, while Ni-decorated ReSe2 exhibited the highest adsorption energy for NH3 (-0.76 eV). In addition, on the basis of transition theory, we found that only Au-ReSe2 and Ni-ReSe2 can serve as reusable chemiresisitve gas sensors for reliable detection of NO and NH3, respectively. Hence, our findings indicate that gas-sensing applications can be significantly improved by utilizing a single-atom-doped ReSe2 monolayer.

2.
ACS Sens ; 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38401047

RESUMO

Rapid and ultrasensitive detection of toxic gases at room temperature is highly desired in health protection but presents grand challenges in the sensing materials reported so far. Here, we present a gas sensor based on novel zero dimensional (0D)/two dimensional (2D) indium oxide (In2O3)/titanium carbide (Ti3C2Tx) Schottky heterostructures with a high surface area and rich oxygen vacancies for parts per billion (ppb) level nitrogen dioxide (NO2) detection at room temperature. The In2O3/Ti3C2Tx gas sensor exhibits a fast response time (4 s), good response (193.45% to 250 ppb NO2), high selectivity, and excellent cycling stability. The rich surface oxygen vacancies play the role of active sites for the adsorption of NO2 molecules, and the Schottky junctions effectively adjust the charge-transfer behavior through the conduction tunnel in the sensing material. Furthermore, In2O3 nanoparticles almost fully cover the Ti3C2Tx nanosheets which can avoid the oxidation of Ti3C2Tx, thus contributing to the good cycling stability of the sensing materials. This work sheds light on the sensing mechanism of heterojunction nanostructures and provides an efficient pathway to construct high-performance gas sensors through the rational design of active sites.

3.
ACS Sens ; 8(12): 4531-4541, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38006356

RESUMO

Inductor-capacitor wireless integrated sensors (LCWISs) featuring untethered and multitarget measurements are promising in health monitoring and human-machine interfaces. However, the lack of a profound understanding of the internal interference hinders the design of the LCWIS, which has a wide remote sensing range and high accuracy. Herein, a mutually exclusive effect of the mutual inductance interferences in LCWIS was revealed and quantified, enabling a design with a wide range of remote sensing (working distance comparable to the single-target device, working radius: 4 mm) and 16% reduced area. As a key to accurate multitarget measurement, a quantified target interference model based on interference decomposition was proposed to understand the target interferences, providing profound guidance for the design of ultra-accurate LCWIS. As a proof, we designed a cellulose-polyacrylate-cellulose LCWIS (CPC-LCWIS) with ultrahigh accuracies (∼1.2% RH and ∼0.18 °C) beyond commercial wired gauges. The CPC-LCWIS with full-coil sensing structures achieved exceptionally high sensitivities (0.36 MHz/°C and 0.25 MHz/% RH). The CPC-LCWIS was validated for health monitoring and human-machine interfaces. The concept studied in this work provides profound guidance for designing a high-performance flexible LCWIS for advanced wearable electronics.


Assuntos
Celulose , Eletrônica , Humanos , Umidade , Temperatura
4.
Phys Chem Chem Phys ; 25(42): 28677-28690, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37849357

RESUMO

Vertical van der Waals (vdW) heterostructures have shown potential for gas sensing owing to their remarkable sensitivity. However, the optimization process for achieving the best gas sensing performance is complicated by the heterostructure's reliance on both physical and electrical characteristics. This study employs density functional theory (DFT) to analyse the structural and electronic parameters of a MoTe2/InN vdW heterostructure. The findings of this study indicate that the vdW heterostructure has a type-II band alignment with higher adsorption energy towards NH3, NO2, and SO2 than the individual monolayers. In specific, the heterostructure is well suited for NO2 detection but has limitations in reliably detecting NH3 and SO2 due to longer recovery times. We find significant hybridization between the adsorbate and interacting surfaces' orbitals and a notable presence of NO2 molecular orbitals in proximity to the Fermi level. Additionally, dielectric and work function modulations offer a viable means to develop optical-based gas sensors that can selectively detect NO2. Our research provides valuable insights into vdW heterostructure design for high-performance gas sensors.

5.
Nanomaterials (Basel) ; 13(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37887965

RESUMO

Carbon nanotube (CNT)/metal composites have attracted much attention due to their enhanced electrical and thermal performance. How to achieve the scalable fabrication of composites with efficient dispersion of CNTs to boost their performance remains a challenge for their wide realistic applications. Herein, the nanoscale dispersion of CNTs in the Stannum (Sn) matrix to boost thermal and electrical conductivity via facile ball milling techniques was demonstrated. The results revealed that CNTs were tightly attached to metal Sn, resulting in a much lower resistivity than that of bare Sn. The resistivity of Sn with 1 wt.% and 2 wt.% CNTs was 0.087 mΩ·cm and 0.056 mΩ·cm, respectively. The theoretical calculation showed that there was an electronic state near the Fermi level, suggesting its electrical conductivity had been improved to a certain extent. In addition, the thermal conductivity of Sn with 2 wt.% CNTs was 1.255 W·m-1·K-1. Moreover, Young's modulus of the composites with CNTs mass fraction of 10 wt.% had low values (0.933 MPa) under low strain conditions, indicating the composite shows good potential for various applications with different flexible requirements. The good electrical and thermal conductive CNT networks were formed in the metal matrix via facile ball milling techniques. This strategy can provide guidance for designing high-performance metal samples and holds a broad application potential in electronic packaging and other fields.

6.
Nanomicro Lett ; 15(1): 149, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286913

RESUMO

Human metabolite moisture detection is important in health monitoring and non-invasive diagnosis. However, ultra-sensitive quantitative extraction of respiration information in real-time remains a great challenge. Herein, chemiresistors based on imine-linked covalent organic framework (COF) films with dual-active sites are fabricated to address this issue, which demonstrates an amplified humidity-sensing signal performance. By regulation of monomers and functional groups, these COF films can be pre-engineered to achieve high response, wide detection range, fast response, and recovery time. Under the condition of relative humidity ranging from 13 to 98%, the COFTAPB-DHTA film-based humidity sensor exhibits outstanding humidity sensing performance with an expanded response value of 390 times. Furthermore, the response values of the COF film-based sensor are highly linear to the relative humidity in the range below 60%, reflecting a quantitative sensing mechanism at the molecular level. Based on the dual-site adsorption of the (-C=N-) and (C-N) stretching vibrations, the reversible tautomerism induced by hydrogen bonding with water molecules is demonstrated to be the main intrinsic mechanism for this effective humidity detection. In addition, the synthesized COF films can be further exploited to effectively detect human nasal and oral breathing as well as fabric permeability, which will inspire novel designs for effective humidity-detection devices.

7.
Nanomaterials (Basel) ; 13(10)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37242076

RESUMO

Two-dimensional (2D) phthalocyanine-based covalent organic frameworks (COFs) provide an ideal platform for efficient and rapid gas sensing-this can be attributed to their regular structure, moderate conductivity, and a large number of scalable metal active centers. However, there remains a need to explore structural modification strategies for optimizing the sluggish desorption process caused by the extensive porosity and strong adsorption effect of metal sites. Herein, we reported a 2D bimetallic phthalocyanine-based COF (COF-CuNiPc) as chemiresistive gas sensors that exhibited a high gas-sensing performance to nitrogen dioxide (NO2). Bimetallic COF-CuNiPc with an asymmetric synergistic effect achieves a fast adsorption/desorption process to NO2. It is demonstrated that the COF-CuNiPc can detect 50 ppb NO2 with a recovery time of 7 s assisted by ultraviolet illumination. Compared with single-metal phthalocyanine-based COFs (COF-CuPc and COF-NiPc), the bimetallic structure of COF-CuNiPc can provide a proper band gap to interact with NO2 gas molecules. The CuNiPc heterometallic active site expands the overlap of d-orbitals, and the optimized electronic arrangement accelerates the adsorption/desorption processes. The concept of a synergistic effect enabled by bimetallic phthalocyanines in this work can provide an innovative direction to design high-performance chemiresistive gas sensors.

8.
ACS Sens ; 8(1): 103-113, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36635889

RESUMO

Flexible chemiresistive gas sensors have attracted growing interest due to their capability in real-time and rapid detection of gas. However, the performance of gas sensors has long been hindered by the poor charge transfer ability between the conventional metal electrode and gas sensing semiconductors. Herein, for the first time, a fully flexible paper-based gas sensor integrated with the Ti3C2Tx-MXene nonmetallic electrode and the Ti3C2Tx/WS2 gas sensing film was designed to form Ohmic contact and Schottky heterojunction in a single gas sensing channel. Ti3C2Tx/WS2 has outstanding physical and chemical properties for both Ti3C2Tx and WS2 nanoflakes, showing high conductivity, effective charge transfer, and abundant active sites for gas sensing. The response of the gas sensor to NO2 (1 ppm) at room temperature is 15.2%, which is about 3.2 and 76.0 times as high as that of the Au interdigital electrode integrated with the Ti3C2Tx/WS2 sensor (4.8%) and the MXene electrode integrated with the Ti3C2Tx sensor (0.2%), respectively. Besides, this design performed at a limit of detection with 11.0 ppb NO2 gas and displayed excellent stability under high humidities. Based on first-principles density functional theory calculation results, the improvement of the gas sensing performance can be mainly attributed to the heterojunction regulation effect, work function matching, and suppressing metal-induced gap states. This work provides a new approach for the design of flexible gas sensors on paper with MXene-based conductive electrodes and gas sensing materials.


Assuntos
Dióxido de Nitrogênio , Temperatura , Condutividade Elétrica , Eletrodos
9.
Nanotechnology ; 34(17)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36689767

RESUMO

To increase the specific capacitance of supercapacitors, polyaniline (PANI) has been chosen as additive electrode material for the pseudocapacitive performance. Here, we synthesize a molecular-level uniform reduced graphene oxide/PANI (rGO/PANI) composite film with high flexibility and conductivity via self-assembly and specific thermal reduction, which performs great potential in flexible supercapacitors with high areal capacitance. Particularly, the electrode of rGO/PANI-42.9% exhibits a high specific areal capacitance (1826 mF cm-2at 0.2 mA cm-2), and it also presents a good cycling stability (it remains 76% of its initial capacitance after 10 500 cycles). Moreover, the specific gravimetric capacitance of rGO/PANI-33.3% reaches up to 256.4 F g-1at 0.2 A g-1, showing greatly enhanced performance compared with the pure rGO electrode (183 F g-1). The results of various characteristic analysis demonstrate that electrochemical performance of the as-prepared rGO/PANI film is closely associated with the uniform distribution of PANI in rGO/PANI composite. Overall, our reported method is convenient and environmental-friendly, and could be beneficial for the development of high-performance capacitive energy storage materials.

10.
ACS Appl Mater Interfaces ; 14(38): 43628-43636, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36108153

RESUMO

Single-walled carbon nanotubes (SWCNTs) are considered to be promising candidates for next-generation near-infrared (NIR) photodetectors due to their extraordinary electrical and optical properties. However, the low separation efficiency of photogenerated carriers limits the full utilization of the potential of pristine SWCNTs as photoactive materials. Herein, we report a novel high-performance visible-NIR SWCNT-based photodetector via interfacial charge-transfer-induced improvement by Au nanoparticle (AuNP) surface doping. Under 1064 nm light illumination, the as-fabricated AuNP/SWCNT photodetector exhibits an excellent photoelectrical performance with a responsivity of 2.16 × 105 A/W and a high detectivity of 1.82 × 1014 Jones, which is three orders of magnitude higher than that of the SWCNT photodetector under the same conditions. Importantly, the interfacial charge transfer between AuNPs and SWCNTs has been first investigated using Raman shift statistics at room temperature. Experimental results indicate that the interfacial charge transfer induced by AuNP doping can reduce the Fermi level of SWCNTs and effectively improve the generation and transport of photogenerated carriers, thereby enhancing the photoelectric performance of SWCNT-based photodetectors. We believe that our results not only demonstrate a facile route to improve the performance of SWCNT-based photodetectors but also provide a novel methodology to characterize the interfacial charge transfer between dopants and SWCNTs.

11.
Nano Lett ; 22(12): 4999-5008, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35679350

RESUMO

The sluggish redox kinetics of sulfur and the uncontrollable growth of lithium dendrites are two main challenges that impede the practical applications of lithium-sulfur (Li-S) batteries. In this study, a multifunctional host with vacancy-rich MoSSe vertically grown on reduced graphene oxide aerogels (MoSSe/rGO) is designed as the host material for both sulfur and lithium. The embedding of Se into a MoS2 lattice is introduced to improve the inherent conductivity and generate abundant anion vacancies to endow the 3D conductive graphene based aerogels with specific sulfiphilicity-lithiophilicity. As a result, the assembled Li-S batteries based on MoSSe/rGO exhibit greatly improved capacity and cycling stability and can be operated under a lean electrolyte (4.8 µL mg-1) and a high sulfur loading (6.5 mg cm-2), achieving a high energy density. This study presents a unique method to unlock the catalysis capability and improve the inherent lithiophilicity by heteroatom doping and defect chemistry for kinetics-enhanced and dendrite-free Li-S batteries.

12.
Nanomaterials (Basel) ; 12(6)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35335714

RESUMO

This study presents three-dimensional (3D) MoS2/reduced graphene oxide (rGO)/graphene quantum dots (GQDs) hybrids with improved gas sensing performance for NO2 sensors. GQDs were introduced to prevent the agglomeration of nanosheets during mixing of rGO and MoS2. The resultant MoS2/rGO/GQDs hybrids exhibit a well-defined 3D nanostructure, with a firm connection among components. The prepared MoS2/rGO/GQDs-based sensor exhibits a response of 23.2% toward 50 ppm NO2 at room temperature. Furthermore, when exposed to NO2 gas with a concentration as low as 5 ppm, the prepared sensor retains a response of 15.2%. Compared with the MoS2/rGO nanocomposites, the addition of GQDs improves the sensitivity to 21.1% and 23.2% when the sensor is exposed to 30 and 50 ppm NO2 gas, respectively. Additionally, the MoS2/rGO/GQDs-based sensor exhibits outstanding repeatability and gas selectivity. When exposed to certain typical interference gases, the MoS2/rGO/GQDs-based sensor has over 10 times higher sensitivity toward NO2 than the other gases. This study indicates that MoS2/rGO/GQDs hybrids are potential candidates for the development of NO2 sensors with excellent gas sensitivity.

13.
ACS Sens ; 7(3): 816-826, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35188381

RESUMO

Practical application of wearable gas-sensing devices has been greatly inhibited by the poorly sensitive and specific recognition of target gases. Rapid charge transfer caused by rich sensory neurons in the biological olfactory system has inspired the construction of a highly sensitive sensor network with abundant defect sites for adsorption. Herein, for the first time, we demonstrate an in situ formed neuron-mimic gas sensor in a single gas-sensing channel, which is derived from lattice deviation of S atoms in Bi2S3 nanosheets induced by gold quantum dots. Due to the favorable gas adsorption and charge transfer properties arising from S vacancies, the fabricated sensor exhibits a significantly enhanced response value of 5.6-5 ppm NO2, ultrafast response/recovery performance (18 and 338 s), and excellent selectivity. Furthermore, real-time visual detection of target gases has been accomplished by integrating the flexible sensor into a wearable device.


Assuntos
Ouro , Dispositivos Eletrônicos Vestíveis , Gases , Neurônios , Enxofre
14.
Nanomicro Lett ; 14(1): 8, 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34859321

RESUMO

Real-time rapid detection of toxic gases at room temperature is particularly important for public health and environmental monitoring. Gas sensors based on conventional bulk materials often suffer from their poor surface-sensitive sites, leading to a very low gas adsorption ability. Moreover, the charge transportation efficiency is usually inhibited by the low defect density of surface-sensitive area than that in the interior. In this work, a gas sensing structure model based on CuS quantum dots/Bi2S3 nanosheets (CuS QDs/Bi2S3 NSs) inspired by artificial neuron network is constructed. Simulation analysis by density functional calculation revealed that CuS QDs and Bi2S3 NSs can be used as the main adsorption sites and charge transport pathways, respectively. Thus, the high-sensitivity sensing of NO2 can be realized by designing the artificial neuron-like sensor. The experimental results showed that the CuS QDs with a size of about 8 nm are highly adsorbable, which can enhance the NO2 sensitivity due to the rich sensitive sites and quantum size effect. The Bi2S3 NSs can be used as a charge transfer network channel to achieve efficient charge collection and transmission. The neuron-like sensor that simulates biological smell shows a significantly enhanced response value (3.4), excellent responsiveness (18 s) and recovery rate (338 s), low theoretical detection limit of 78 ppb, and excellent selectivity for NO2. Furthermore, the developed wearable device can also realize the visual detection of NO2 through real-time signal changes.

15.
Phys Chem Chem Phys ; 23(34): 18359-18368, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34612377

RESUMO

Two-dimensional (2D) layered nanomaterials have attracted increasing attention in gas sensing due to their graphene-like properties. Although the gas sensing performances of 2D layered semiconductor transition metal dichalcogenides (TMDs), including MoS2, WS2, MoSe2 and WSe2, have been extensively studied, it has remained a grand challenge to develop a high-performance gas sensing material that can meet practical applications. Tantalum disulfide (TaS2), as a metallic TMD with low resistance and high current signal, has great promise in high-performance gas sensing. In stark contrast with Mo and W, Ta has a stronger positive charge, which contributes to a higher surface energy to capture gas molecules. Herein, through calculating the adsorption energy, charge transfer, electronic structure, and work function of the adsorption system with first-principles calculations, we first systematically studied the performance of noble metal atom substitution doping on a TaS2 monolayer for toxic nitrogen-containing gas (NH3, NO and NO2) sensing. We found that the TaS2 monolayer exhibits excellent NO sensing performance with an adsorption energy of 0.49 eV and a charge transfer of 0.17 e. However, it has a considerable adsorption energy (-0.22 and -0.39 eV) to NH3 and NO2 molecules, but a low charge transfer (-0.03 and 0.04 e) between the gas molecules and the TaS2 monolayer. To further enhance the gas-sensing performance of the TaS2 monolayer, noble metal atoms (Ag, Au, Pd and Pt) were substitutionally doped into the lattice of the TaS2 monolayer. The results showed that the values of adsorption energy and charge transfer can be significantly improved, and the electronic structure and work function of the doping system has also greatly changed, which makes it much easier to detect the changes in electrical signal due to gas adsorption. Our work indicates that the intrinsic as well as the noble metal doped TaS2 monolayers are promising candidates for high-performance gas sensors.

16.
Nanotechnology ; 32(50)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34517362

RESUMO

Anode materials based on lithium titanate (LTO)/graphene composites are considered as ideal candidates for high-rate lithium-ion batteries (LIBs). Considering the blocking effects of graphene nanosheets in electrodes during ion-transfer processes, construction of LTO/graphene composite structures with enhanced electrical and ionic conductivity via facile and scalable techniques is still challenging for high-rate LIB. In this work, structures of anode materials based on LTO nanoplates embedded with graphene quantum dots (GQDs) are demonstrated for high-rate LIB. The hybrids can be facilely prepared viain situintroduction of GQDs during the process LTO preparation, which enables a uniform dispersion of GQDs within LTO. This method is convenient, rapid, and can be easily scaled-up. The introduction of 0.05 wt.% GQDs can greatly enhance the electrochemical performance of the electrodes. The electrodes with 0.05 wt.% GQDs deliver a specific discharge capacity of 185, 181 and 179 mAh g-1at 5, 10, and 20 C, respectively. The performance enhancement is suggested to be due to the synergistic interactions between LTO and GQDs. The strategy as well as as-designed structures of LTO/GQDs show potentials for application as high-rate anode materials in LIBs application.

17.
Nanotechnology ; 32(44)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34315147

RESUMO

Tungsten disulfide (WS2) nanosheets (NSs) have become a promising room-temperature gas sensor candidate due to their inherent high surface-to-volume ratio, tunable electrical properties, and high on-state current density. For further practical applications of WS2-based gas sensors, it is still necessary to overcome the insensitive response and incomplete recovery at room temperature. In this work, we controllably synthesized high-performance ammonia (NH3) gas sensor based on CuO decorated WS2NSs. The optimized p-p WS2/CuO heterojunctions improve the surface catalytic effect, thereby enhancing the gas-sensing performance. The pure WS2NSs-based gas sensors showed a low response and an incomplete recovery in the case of NH3sensing. After the functionalization of CuO nanoparticles, the WS2/CuO heterostructure-based gas sensor exhibits an improved response value of 40.5% to 5  ppm NH3and full recoverability without any external assistance. Density functional theory calculations illustrate that the adsorption of CuO for NH3is much superior to WS2. The p-p heterojunctions strategy demonstrated in this work has great potential in the design of sensitive materials for gas sensors, and provides useful guidance for enhancing the room-temperature sensitivity and recoverability.

18.
ACS Appl Mater Interfaces ; 13(23): 27270-27277, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34081435

RESUMO

High-capacity silicon (Si) is recognized as a potential anode material for high-performance lithium-ion batteries (LIBs). Unfortunately, large volume expansion during discharge/charge processes hinders its areal capacity. In this work, we design a flexible graphene-fiber-fabric (GFF)-based three-dimensional conductive network to form a binder-free and self-standing Si anode for high-performance LIBs. The Si particles are strongly wrapped in graphene fibers. The substantial void spaces caused by the wrinkled graphene in fibers enable effective accommodation of the volume change of Si during lithiation/delithiation processes. The GFF/Si-37.5% electrode exhibits an excellent cyclability with a specific capacity of 920 mA h g-1 at a current density of 0.4 mA cm-2 after 100 cycles. Furthermore, the GFF/Si-29.1% electrode exhibits an excellent reversible capacity of 580 mA h g-1 at a current density of 0.4 mA cm-2 after 400 cycles. The capacity retention of the GFF/Si-29.1% electrode is up to 96.5%. More importantly, the GFF/Si-37.5% electrode with a mass loading of 13.75 mg cm-2 achieves a high areal capacity of 14.3 mA h cm-2, which outperforms the reported self-standing Si anode. This work provides opportunities for realizing a binder-free, flexible, and self-standing Si anode for high-energy LIBs.

19.
Nanoscale Res Lett ; 16(1): 75, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33929622

RESUMO

To achieve better antitumour efficacy, it is urgent to improve anticancer drug delivery efficiency in targeting cancer cells. In this work, chitosan-functionalized graphene oxide (ChrGO) nanosheets were fabricated via microwave-assisted reduction, which were employed to the intracellular delivery nanosystem for anticancer drug agent in breast cancer cells. Drug loading and release research indicated that adriamycin can be efficiently loaded on and released from the ChrGO nanosheets. Less drug release during delivery and better biocompatibility of ChrGO/adriamycin significantly improve its safety and therapeutic efficacy in HER2-overexpressing BT-474 cells. Furthermore, ChrGO/adriamycin in combination with trastuzumab exhibited synergistic antitumour activity in BT-474 cells, which demonstrated superior therapeutic efficacy compared with each drug alone. Cells treated with trastuzumab (5 µg/mL) or equivalent ChrGO/adriamycin (5 µg/mL) each elicited 54.5% and 59.5% cell death, respectively, while the combination treatment with trastuzumab and ChrGO/adriamycin resulted in a dramatic 88.5% cell death. The dual-targeted therapy displayed higher apoptosis, indicating superior therapeutic efficacy due to the presence of different mechanisms of action. The combined treatment of ChrGO/adriamycin and trastuzumab in BT-474 cells induced cell cycle arrest and apoptosis, which ultimately led to the death of augmented cancer cells. This work has provided a facile microwave-assisted fabrication of ChrGO as a controlled and targeted intracellular drug delivery nanosystem, which is expected to be a novel promising therapy for treating HER2-overexpressing breast cancer cells.

20.
Langmuir ; 37(4): 1596-1604, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33481594

RESUMO

Rational design and scalable construction of antibacterial mediators based on unique graphene architectures with highly efficient antibacterial ability and significant biocompatibility are challenging. Herein, sulfur-doped graphene skeletons uniformly decorated with metal oxide nanoparticles were designed and constructed via one-step laser-induced microexplosive techniques and demonstrated for the first time as highly efficient antibacterial agents. The optical density and flat colony counting methods demonstrated that the as-designed laser-induced MoOx/sulfur-doped graphene hybrids exhibited exceptional activity inhibition of Escherichia coli and Staphylococcus aureus. Moreover, the bacteria were treated with an impressive laser-induced MoOx/sulfur-doped graphene colloidal solution of concentration as low as 1 mg/mL for 4 h, leading to an excellent viability loss of 85% for the two bacteria. Cell toxicity experiments proved that the biological toxicity of laser-induced MoOx/sulfur-doped graphene to pig sperm cells was negligible. The molecular dynamics calculations proposed that the intrinsic interaction with N-acetylglucosamine at the cell wall and the high-efficiency synergistic effect of sulfur-doped graphene and MoOx played the key role in inhibiting the viability of bacteria. This work provides new insights for a novel structure design and opens up a potential route to construct antibacterial agents with high efficiency for clinical application.


Assuntos
Grafite , Animais , Antibacterianos/toxicidade , Grafite/toxicidade , Lasers , Staphylococcus aureus , Enxofre , Suínos
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