Micro & Nano Letters最新文献_第5页

Highly Sensitive Sensor for the Determination of Riboflavin Using Thionine Coated Cadmium Selenide Quantum Dots Modified Graphite Electrode 硫氨酸包覆硒化镉量子点修饰石墨电极测定核黄素的高灵敏度传感器

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-08-13 DOI: 10.3390/micro3030048

A. Kalaivani, R. Suresh Babu, S. Sriman Narayanan

In this paper, the electrochemical non-enzymatic detection of Riboflavin (RF) was proposed based on its catalytic reduction in a Thionine-coated Cadmium Selenide Quantum dots (TH@CdSe QDs)-modified paraffin wax-impregnated graphite electrode (PIGE) that was prepared using a novel approach. The synthesized TH@CdSe QDs were confirmed by UV-Vis spectroscopy, Confocal Raman Microscopy and High Resolution Transmission Electron Microscopy (HRTEM) studies. The electrochemical response of the TH@CdSe QDs-modified PIGE was studied by cyclic voltammetry. The voltammetric response of RF at the TH@CdSe QDs-modified PIGE showed higher current than the bare PIGE. Under optimum conditions, the electrocatalytic reduction currents of RF was found to be linearly related to its concentration over the range of 1.6 × 10−7 M to 1.4 × 10−4 M with a detection limit of 53 × 10−9 M (S/N = 3). The TH@CdSe QDs-modified PIGE was utilized as an amperometric sensor for the detection of RF in flow systems was performed by carrying out hydrodynamic and chronoamperometric experiments. The TH@CdSe QDs-modified PIGE showed very good stability and a longer shelf life. The applicability of the fabricated electrode was justified by the quantification of RF in commercial tablets.

本文提出了一种新的方法，利用巯基包覆硒化镉量子点(TH@CdSe QDs)修饰石蜡浸渍石墨电极(PIGE)催化还原核黄素(RF)的电化学非酶检测方法。通过紫外可见光谱、共聚焦拉曼显微镜和高分辨率透射电子显微镜(HRTEM)对合成的TH@CdSe量子点进行了验证。采用循环伏安法研究了TH@CdSe qds修饰的PIGE的电化学响应。RF在TH@CdSe qds修饰的PIGE处的伏安响应显示出比裸PIGE更高的电流。在最佳条件下，RF的电催化还原电流与其浓度在1.6 × 10−7 M ~ 1.4 × 10−4 M范围内呈线性关系，检出限为53 × 10−9 M (S/N = 3)。利用TH@CdSe qds改进的PIGE作为电流传感器，通过流体动力学和计时电流实验对流动系统中的RF进行了检测。TH@CdSe qds修饰的PIGE具有很好的稳定性和较长的保质期。通过对市售片剂中RF的定量分析，验证了所制备电极的适用性。

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引用次数: 0

Self-trigger and on-demand drug delivery system based on TiO2 nanotube arrays and its drug release behaviour 基于TiO2纳米管阵列的自触发按需给药系统及其药物释放行为

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-08-02 DOI: 10.1049/mna2.12173

Tao Zhang, Nannan Liu, Chunling Xie, Xiufeng Xiao

The foundation of drug delivery systems based on titanium dioxide nanotube arrays has become an important means to increase the drug release performance of bone implantation materials. However, most of the conventional platforms have some disadvantages, such as large sudden release, uncontrollable, unintelligent, or not on-demand drug release process. Herein, the authors develop a unique self-triggering drug release system (SDDS), utilizing the advantages of 1-Tetradecanol (TD), such as decent biocompatibility, a phase transition temperature of 37.8°C, and the inexistence of complex chemical reaction process. The establishment of the platform can make a large amount of the anti-inflammatory drug (ibuprofen, IBU) released when the body or the affected area is inflamed, that is, when the temperature rises. Conversely, only a small amount or no drug is released when there is no inflammation, thereby achieving self-trigger release and on-demand release. The experimental results show that the system combines good self-trigger release properties, release sensitivity, drug release cycle, and low selectivity to the loaded drugs.

基于二氧化钛纳米管阵列的药物递送系统的建立已成为提高骨植入材料药物释放性能的重要手段。然而，大多数常规平台都存在一些缺点，如突然释放量大、不可控、不智能或药物释放过程不按需。在此，作者开发了一种独特的自触发药物释放系统（SDDS），利用1-十四醇（TD）的优点，如良好的生物相容性、37.8°C的相变温度和不存在复杂的化学反应过程。该平台的建立可以使抗炎药（布洛芬、IBU）在身体或患处发炎时，即温度升高时大量释放。相反，在没有炎症的情况下，只有少量或没有药物释放，从而实现自触发释放和按需释放。实验结果表明，该系统具有良好的自触发释放特性、释放灵敏度、药物释放周期和对负载药物的低选择性。

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引用次数: 0

Microfluidic System for Cell Mixing and Particle Focusing Using Dean Flow Fractionation 采用迪安流分馏的微流体混合和颗粒聚焦系统

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-07-31 DOI: 10.3390/micro3030047

Alexander Wiede, O. Stranik, A. Tannert, U. Neugebauer

Recent developments in the field of additive manufacturing processes have led to tremendous technological progress and opened directions for the field of microfluidics. For instance, new flexible materials for 3D printing allow the substitution of polydimethylsiloxane (PDMS) in microfluidic prototype development. Three-dimensional-printed microfluidic components open new horizons, in particular for the automated handling of biological cells (e.g., eukaryotic cells or bacteria). Here, we demonstrate how passive mixing and passive separation processes of biological cells can be realized using 3D printing concepts for rapid prototyping. This technique facilitates low-cost experimental setups that are easy to modify and adopt for specific detection and diagnostic purposes. In particular, printing technologies based on fused deposition modeling and stereolithography are used and their realization is discussed. Additive technologies enable the fabrication of multiplication mixers, which overcome shortcomings of current pillar or curve-based techniques and enable efficient mixing, also of biological cells without affecting viability. Using standard microfluidic components and state-of-the art 3D printing technologies, we realize a separation system based on Dean flow fragmentation without the use of PDMS. In particular, we describe the use of a 3D-printed helix for winding a capillary for particle flow and a new chip design for particle separation at the outlet. We demonstrate the functionality of the system by successful isolation of ~12 µm-sized particles from a particle mixture containing large (~12 µm, typical size of eukaryotic cells) and small (~2 µm, typical size of bacteria or small yeasts) particles. Using this setup to separate eukaryotic cells from bacteria, we could prove that cell viability is not affected by passage through the microfluidic systems.

增材制造工艺领域的最新发展带来了巨大的技术进步，为微流体领域开辟了方向。例如，用于3D打印的新型柔性材料允许在微流体原型开发中替代聚二甲基硅氧烷(PDMS)。三维打印微流体组件开辟了新的领域，特别是对生物细胞(如真核细胞或细菌)的自动处理。在这里，我们展示了如何使用3D打印概念实现生物细胞的被动混合和被动分离过程。这种技术有助于低成本的实验设置，易于修改和采用特定的检测和诊断目的。特别是基于熔融沉积建模和立体光刻的印刷技术，并讨论了它们的实现。增材技术使倍增混合器的制造成为可能，它克服了当前柱式或曲线式技术的缺点，使生物细胞在不影响生存能力的情况下也能有效混合。利用标准的微流体元件和最先进的3D打印技术，我们实现了一个基于Dean流破碎的分离系统，而不使用PDMS。特别地，我们描述了使用3d打印螺旋缠绕颗粒流的毛细管和用于出口颗粒分离的新芯片设计。我们通过从含有大颗粒(~12 μ m，真核细胞的典型尺寸)和小颗粒(~2 μ m，细菌或小酵母的典型尺寸)的颗粒混合物中成功分离出~12 μ m大小的颗粒，证明了该系统的功能。利用这种装置分离真核细胞和细菌，我们可以证明细胞活力不受通过微流体系统的影响。

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引用次数: 0

Photodegradation of Tropaeolin O in the Presence of Ag-Doped ZnO Nanoparticles 银掺杂ZnO纳米粒子对Tropaeolin O的光降解研究

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-07-28 DOI: 10.3390/micro3030045

S. Bailón-Ruiz, Y. Cedeño-Mattei, K. Torres-Torres, L. Alamo-Nole

Azo dyes such as Tropaeolin O have diverse applications in the textile, food, and biomedical industries. However, their recalcitrant properties make them toxic substances in surface waters. Nanocatalysts are photoactive nanoparticles that generate reactive oxygen species to destroy organic compounds. Moreover, the presence of dopant agents in the nanoparticles’ crystalline structure efficiently enhances photocatalytic activity. Ag-doped ZnO nanoparticles were prepared in ethylene glycol at 197 °C and characterized by UV-Vis absorption, photoluminescence, high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX), and electron diffraction (ED). The particles were mainly spherical with a size of ~10 nm, a hexagonal structure, and an elemental composition of 56.2% Zn, 37.8% O, and 5.9% Ag. The particles evidenced a broad absorption peak in the UV region and two emission peaks. Absorption analysis indicates that 92% and 58% of Tropaeolin O were degraded using 100 and 50 ppm of Ag-doped ZnO nanoparticles, respectively, during the first 550 min. Ion chromatograms selected using quadrupole time-of-flight liquid chromatography-mass spectrometry (QTOF-LC-MS) indicate a complete Tropaeolin O degradation (295.04 m/z) during the first 330 min. Initially, the nanocatalyst attacks the electron-rich groups (-OH and -NH), generating the 277.03 m/z [M-OH]+ and 174.02 m/z (molecule rupture on the azo group). In addition, small oxidized fragments 167.03 m/z and 114.03 m/z confirm the nanoparticles’ photocatalytic capacity, and oxidized chains indicate the tropaeolin’s opening rings (including phtalic acids) and mineralization.

偶氮染料如Tropaeolin O在纺织、食品和生物医学工业中有多种应用。然而，它们的顽固性使它们成为地表水中的有毒物质。纳米催化剂是光活性纳米颗粒，产生活性氧来破坏有机化合物。此外，掺杂剂在纳米颗粒晶体结构中的存在有效地提高了光催化活性。在197°C的乙二醇中制备了ag掺杂ZnO纳米颗粒，并通过紫外可见吸收、光致发光、高分辨率透射电子显微镜(HRTEM)、能量色散x射线能谱(EDX)和电子衍射(ED)对其进行了表征。颗粒主要为球形，尺寸约为10 nm，呈六边形结构，元素组成为56.2% Zn、37.8% O和5.9% Ag。粒子在紫外区有一个宽的吸收峰和两个发射峰。吸收分析表明，在前550分钟内，使用100 ppm和50 ppm的ag掺杂ZnO纳米粒子分别降解了92%和58%的Tropaeolin O。使用四极杆飞行时间-液相色谱-质谱(QTOF-LC-MS)选择的离子色谱图表明，在前330分钟内，Tropaeolin O完全降解(295.04 m/z)。产生277.03 m/z [m - oh]+和174.02 m/z(偶氮基团上的分子断裂)。此外，167.03 m/z和114.03 m/z的小氧化片段证实了纳米粒子的光催化能力，氧化链表明了tropaeolin的开环(包括酞酸)和矿化。

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引用次数: 0

Extraction and Modification of Cellulose Microfibers Derived from Biomass of the Amazon Ochroma pyramidale Fruit 亚马孙黑锥果生物质纤维素微纤维的提取与改性

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-07-28 DOI: 10.3390/micro3030046

A. Rocha, B. D. A. Feitosa, A. S. Carolino, Ronald Zico de Aguiar Nunes, Célio Matias Airone Macalia, Kalil Araújo da Silva, Cleverton Oliveira Dias, S. M. de Souza, P. Campelo, J. Bezerra, E. Sanches

Microfibers are important to several areas of human lifestyle, and the knowledge about their physicochemical characteristics allows for proposing new technological applications. The in natura microfiber of Ochroma pyramidale fruit (IN sample) and its extracted pulp (PU sample) were evaluated by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetry and Differential Scanning Calorimetry (TG/dTG and DSC). Microfibers were composed mainly of (68 ± 1)% holocellulose, (35.8 ± 0.1)% cellulose, (32 ± 3)% lignin and (3.7 ± 0.3)% extractives. The XRD pattern of the PU sample revealed that the mercerization process resulted in the change of the cellulose crystal structure from Iα type (triclinic) to type II (monoclinic). The SEM technique showed that the IN sample presented regular cylindrical/hollow-shaped wire-like microfibers with diameters ranging from 5 µm to 25 µm. However, the mercerization process changed their natural morphology. A significant change in the FTIR spectra after the removal of hemicellulose and lignin components was observed: weak bands at 1739 cm−1 (C=O stretching of lignin and hemicellulose fractions), 1463 cm−1 (CH3 of lignin) and 1246 cm−1 (C-O of lignin) were still observed in the PU sample, indicating that the lignin was not completely removed due to the natural difficulty of isolating pure cellulose. The TG/dTG and DSC evaluation revealed a temperature increase of the second thermal event (starting at 235 °C) in the PU sample, which was assigned to the cellulose and residual hemicellulose degradation. Then, this work aimed to disseminate and characterize a microfiber with unusual characteristics still little explored by the scientific community, as well as its cellulosic pulp, providing information that may be useful in its application in different industries, enabling the positive development of new biocompatible, renewable and sustainable materials.

微纤维对人类生活方式的几个方面都很重要，对其物理化学特性的了解可以提出新的技术应用。采用x射线衍射(XRD)、扫描电镜(SEM)、傅里叶变换红外光谱(FTIR)、热重法和差示扫描量热法(TG/dTG和DSC)等分析方法，对天然锥体果(in样品)及其提取果肉(PU样品)的超细纤维进行了表征。微纤维主要由(68±1)%的全新纤维素、(35.8±0.1)%的纤维素、(32±3)%的木质素和(3.7±0.3)%的萃取物组成。PU样品的XRD分析表明，丝光过程导致纤维素晶体结构由Iα型(三斜)转变为II型(单斜)。扫描电镜技术表明，IN样品呈现出规则的圆柱形/空心线状微纤维，直径范围为5µm ~ 25µm。然而，丝光过程改变了它们的自然形态。在去除半纤维素和木质素组分后，FTIR光谱发生了显著变化:在PU样品中仍然观察到1739 cm−1(木质素和半纤维素组分的C=O拉伸)，1463 cm−1(木质素的CH3)和1246 cm−1(木质素的C-O)处的弱带，这表明由于分离纯纤维素的天然困难，木质素没有被完全去除。TG/dTG和DSC评估显示PU样品中的第二次热事件(开始于235℃)温度升高，这归因于纤维素和残余半纤维素的降解。然后，这项工作旨在传播和表征一种具有不同寻常特性的超细纤维，科学界仍然很少探索它的纤维浆，为其在不同行业的应用提供有用的信息，从而促进新的生物相容性，可再生和可持续材料的积极发展。

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引用次数: 0

A chitosan-based hydrogel containing zinc oxide nanoparticles as a carrier for improving antibacterial activity and controlling the release of antibiotics 一种以氧化锌纳米粒子为载体的壳聚糖水凝胶，用于提高抗菌活性和控制抗生素的释放

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-07-04 DOI: 10.1049/mna2.12172

Ali Rastegari, Fatemeh Hasanshakir, Zohreh Mohammadi, Fatemeh Saadatpor, Homa Faghihi, Fatemeh Moraffah

Microbial infections are considered one of the most important concerns of the world community. Developing drug delivery systems based on formulation of nanoparticles (NPs) with antimicrobial agents has shown beneficial effectiveness against microbial infections and related antimicrobial resistance. In this study, the authors prepared and characterized a chitosan-based hydrogel loaded with zinc oxide NPs for controlling the release of vancomycin and also improving its antibacterial effect. Characterization studies demonstrated that the developed biopolymeric hydrogel was able to sustain and control the release of vancomycin in response to acidic media for 96 h. Furthermore, antimicrobial studies showed significant and efficient antibacterial activity of prepared hydrogel against Staphylococcus aureus and Pseudomonas aeruginosa. Based on the obtained results, it can be concluded that the prepared chitosan hydrogel (CH) containing zinc oixde (ZnO) NPs has a desirable activity for controlling the release of vancomycin and improving its antibacterial properties.

微生物感染被认为是国际社会最关心的问题之一。基于纳米颗粒（NP）与抗菌剂的配方开发的药物递送系统已显示出对抗微生物感染和相关抗菌耐药性的有益效果。在本研究中，作者制备并表征了一种负载氧化锌纳米颗粒的壳聚糖水凝胶，用于控制万古霉素的释放并提高其抗菌效果。表征研究表明，所开发的生物聚合物水凝胶能够维持和控制万古霉素在酸性介质中的释放96小时。此外，抗菌研究表明，所制备的水凝胶对金黄色葡萄球菌和铜绿假单胞菌具有显著而有效的抗菌活性。基于所获得的结果，可以得出结论，所制备的含有氧化锌（ZnO）NPs的壳聚糖水凝胶（CH）在控制万古霉素的释放和提高其抗菌性能方面具有理想的活性。

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引用次数: 0

Simulation of the Dynamics of Supersonic N-Crowdions in fcc Lead and Nickel 超声速氮离子在fcc铅镍中的动力学模拟

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-07-04 DOI: 10.3390/micro3030044

A. Bayazitov, A. Semenov, S. V. Dmitriev

In the case where an interstitial atom is located in a close-packed atomic row of the crystal lattice, it is called a crowdion. Crowdions play an important role in the processes of mass and energy transfer resulting from irradiation, severe plastic deformation, ion implantation, plasma and laser processing, etc. In this work, supersonic N-crowdions (N=1, 2) in fcc lattices of lead and nickel are studied by the method of molecular dynamics. Modeling shows that the propagation distance of a supersonic 2-crowdion in lead at a high initial velocity is less than that of a supersonic 1-crowdion. In other fcc metals studied, including nickel, supersonic 2-crowdions have a longer propagation distance than 1-crowdions. The relatively short propagation distance of supersonic 2-crowdions in lead is due to their instability and rapid transformation into supersonic 1-crowdions. This feature of the dynamics of supersonic N-crowdions in lead explains its high radiation-shielding properties.

在这种情况下，一个间隙原子位于一个紧密排列的原子行晶体晶格，它被称为拥挤。群体在辐照、剧烈塑性变形、离子注入、等离子体和激光加工等过程中产生的质量和能量传递过程中起着重要作用。本文用分子动力学方法研究了铅和镍的fcc晶格中N= 1,2的超声速N群离子。模拟结果表明，在高初速条件下，超声速2-crowdion在铅中的传播距离小于超声速1-crowdion。在所研究的其他fcc金属中，包括镍，超音速2群离子比1群离子具有更长的传播距离。超声速2-群在铅中的传播距离相对较短是由于它们的不稳定性和向超声速1-群的快速转化。超声速n-离子在铅中的动力学特性解释了其高辐射屏蔽性能。

引用次数: 0

Preparation of chitosan-embedded recombinant human epidermal growth factor nanoparticles as accelerating compounds for skin remodelling in chronic lesions 壳聚糖包埋重组人表皮生长因子纳米颗粒作为慢性病变皮肤重塑促进剂的制备

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-07-03 DOI: 10.1049/mna2.12171

Saadeh Hashemi, Elnaz Mihandoost, Sepideh Khaleghi

The chronic lesion has become a major biological difficulty. Using nanoparticles as drug delivery systems is remarkable nowadays. The unique properties of chitosan in combination with epidermal growth factor (EGF) can accelerate the wound-healing process.

In this study, Chitosan-EGF (CS-EGF) nanoparticles were manipulated and characterized by Transmission Electron Microscopy (TEM) microscopy, dynamic light scattering (DLS) method, and Fourier Transform Infrared Spectroscopy (FTIR) radiation. The antibacterial effect was estimated by minimum inhibitory concentration (MIC)/minimum bactericidal concentration (MBC) methods and the proliferation assay was measured on the HFF-1 (human fibroblast cell line). Then, migration assay was accomplished and the gene expression analysis for transforming growth factor-beta (TGF-β), vascular endothelial growth factor (VEGF), and platelets-derived growth factor (PDGF) was manipulated by the real-time-PCR method. The obtained results were considered statistically significant with P < 0.05.

Obtained results illustrated no toxic effect on the HFF-1 cell line treated with CS-EGF. In cellular proliferation and migration assays, CS-EGF nanoparticles demonstrated 2-folds higher than the control. In the duration of 72 h of the experiment, and concentration of 10 µM, 90 ±10% of cells were migrated and the whole scratch was covered by fibroblasts. The real-time-PCR analysis also showed 7.5, 4.5-, and 7-fold upregulation of all TGF-β, VEGF, and PDGF genes in comparison with the control group.

This study confirmed that using chitosan nanoparticles as a carrier for EGF can accelerate cellular remodelling and annihilate bacterial infection in the process of treatment. As CS-EGF nanoparticles in the acceleration of the skin remodelling process showed promising results, subsequent studies might be useful.

慢性病变已成为一个主要的生物学难题。如今，使用纳米颗粒作为药物递送系统是非常了不起的。壳聚糖与表皮生长因子（EGF）的结合具有独特的特性，可以加速伤口愈合过程。本研究采用透射电子显微镜（TEM）、动态光散射（DLS）和傅立叶变换红外光谱（FTIR）对壳聚糖-EGF（CS-EGF）纳米粒子进行了表征。通过最小抑菌浓度（MIC）/最小杀菌浓度（MBC）方法估计抗菌效果，并在HFF-1（人成纤维细胞系）上测量增殖测定。然后，完成迁移测定，并通过实时PCR方法对转化生长因子β（TGF-β）、血管内皮生长因子（VEGF）和血小板衍生生长因子（PDGF）的基因表达进行分析。所获得的结果被认为具有统计学意义；0.05。得到的结果表明对用CS-EGF处理的HFF-1细胞系没有毒性作用。在细胞增殖和迁移测定中，CS-EGF纳米颗粒比对照高出2倍。在实验的72小时内，浓度为10µM，90±10%的细胞迁移，整个划痕被成纤维细胞覆盖。实时PCR分析还显示，与对照组相比，所有TGF-β、VEGF和PDGF基因上调7.5倍、4.5倍和7倍。本研究证实，使用壳聚糖纳米粒子作为EGF的载体可以加速细胞重塑，并在治疗过程中消灭细菌感染。由于CS-EGF纳米颗粒在加速皮肤重塑过程中显示出有希望的结果，后续的研究可能是有用的。

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引用次数: 0

Fabrication of Circular Cross-Section Microchannels with 3-D Lattice Arrangement and Their Use as On-Off Valves 三维点阵布置圆形截面微通道的制备及其开关阀的应用

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-06-30 DOI: 10.3390/micro3030043

Kaori Uehara, Yutaka Hori, T. Ishigure

In this paper, circular cross-section microchannels with 3-D lattice arrangements are designed and fabricated using the Mosquito method in order to construct on-off valves. The 3-D microchannels with on-off valves consist of two types of lines: the flow lines for chemical liquid flow and the control lines to activate the valves. We confirmed that both a circular cross-section and a PDMS with low elastic modulus used as the microchannel material contribute to a valve that can be closed with a lower pressure. Then, we demonstrated liquid flow to evaluate the functionality of the valve. Fluorescein solution was flown into a flow line. We found that the fluorescence intensity decreases at the intersection between the flow and control lines when the flow line is closed by the inflation of the control line, experimentally confirming the functionality of the valve microchannels fabricated via the Mosquito method.

本文采用蚊子法设计和制作了具有三维点阵排列的圆形截面微通道，用于构造开关阀。带有开关阀的三维微通道由两类管线组成:用于化学液体流动的管线和激活阀门的控制线。我们证实，圆形截面和低弹性模量的PDMS用作微通道材料有助于用较低的压力关闭阀门。然后，我们演示了液体流量来评估阀门的功能。将荧光素溶液送入流水线。我们发现，当控制线膨胀关闭流线时，流线和控制线相交处的荧光强度下降，实验证实了通过蚊子方法制备的阀门微通道的功能。

引用次数: 0

Biosynthesis of ZnO.Ag2O3 using aqueous extract of Haplophyllum obtusifolium: Characterization and cell toxicity activity against liver carcinoma cells 利用钝叶单叶藻水提取物生物合成ZnO.Ag2O3：特性和对肝癌细胞的细胞毒性

IF 1.3 4区材料科学 Q3 Physics and Astronomy

Micro & Nano Letters

Pub Date : 2023-06-25 DOI: 10.1049/mna2.12170

Majid Halimi Khalil Abad, Mohabat Nadaf, Mohammad Ehsan Taghavizadeh Yazdi

The zinc oxide-silver oxide nanocomposite (ZnO.Ag₂O₃ particles) was prepared by using an aqueous plant extract of Haplophyllum obtusifolium for the first time. Powder X-ray diffraction (PXRD), Fourier transforms spectroscopy (FTIR), field emission microscopy (FESEM), energy dispersive X-ray analysis (EDX), and transmission electron microscopy (TEM) were applied to analyze the structure, functional groups, morphology, and purity of the prepared nanocomposite. PXRD revealed the formulation of ZnO.Ag₂O₃ for the particles. The investigation of functional groups has demonstrated the presence of some carbonated impurities along with absorbed water in the composition of the ZnO.Ag₂O₃ nanocomposite. Morphologically, particles have formed a petal-like shape with different sizes. The EDX analysis also confirmed the composition of the prepared sample and the presence of 4.78% silver in the formula. Additionally, the TEM analysis revealed spherical and rectangular shapes with a particle size of 80.43 ± 46.73 nm. Moreover, the ZnO.Ag₂O₃ particles were used against cancer cells, which has shown synthesized NCs have a toxic effect against liver cancer cells in a concentration and time-dependent manner.

首次利用钝叶单叶藻的植物提取物制备了氧化锌-氧化银纳米复合材料（ZnO.Ag2O3颗粒）。应用粉末X射线衍射（PXRD）、傅立叶变换光谱（FTIR）、场发射显微镜（FESEM）、能量色散X射线分析（EDX）和透射电子显微镜（TEM）对制备的纳米复合材料的结构、官能团、形态和纯度进行了分析。PXRD揭示了ZnO的组成。颗粒为Ag2O3。对官能团的研究表明，在ZnO的组成中存在一些碳酸杂质以及吸收的水。Ag2O3纳米复合材料。从形态上看，颗粒形成了大小不等的花瓣状。EDX分析还证实了所制备的样品的组成以及在该配方中存在4.78%的银。此外，TEM分析显示，颗粒大小为80.43±46.73 nm的球形和矩形。此外，ZnO。使用Ag2O3颗粒对抗癌症细胞，这表明合成的NC以浓度和时间依赖的方式对癌症肝癌细胞具有毒性作用。

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引用次数: 4