查找使用阿拉丁产品的科研文献

Hollow MOFs-based biomimetic encoded microspheres as versatile probes for dual-mode ratiometric fluorescence sensing platform coupling instrumental and smartphone-assisted analysis of Sudan I

Xueyong Qiao,Rongrong Yang,Zhonghui Han,Lei Lü,Xiaolei Zhao,Jinxing He

Background The accurate, ultrasensitive, and on-site detection of pollutants is critical for public health. As a carcinogen, Sudan I is strictly forbidden from use in food products at any levels. However, the conventional method suffers from the high instrument cost and complex procedure, resulting in poor sensitivity, low portability, and long detection time. A ratiometric fluorescence sensor offers a promising prospect for the ultra-rapid, high sensitivity, visual detection, and “point-of-care” testing. The objective of this work was to address the insufficient selectivity of fluorescence probe and enhance the recognition capability and mass transfer rate while diversifying their signal output modes. Results In this study, a novel hollow metal-organic frameworks (MOFs) structural biomimetic nanosensor was developed for the specific recognition and rapid analysis of Sudan I. The sensor separately integrated CsPbCl 1.5 Br 1.5 perovskite quantum dots and CdSe/ZnS quantum dots as dual-emission fluorophores into hollow MOFs-based molecularly imprinted polymers, acting as the recognition element and a signal carrier. The hollow architecture significantly improved mass transfer efficiency, reducing response time to 10 min. The developed nanosensor in instrumental analysis mode exhibited a linearity within the range of 2.00–200.00 μg L −1 at a method's detection limit of 1.00 μg L −1 , indicating high accuracy with recoveries of 88.00–109.65 % in real samples. Furthermore, a smartphone-based portable platform was designed for on-site intelligence detection with a good linear range (0.15–5.00 μg mL −1 ), a method's detection limit of 0.05 μg mL −1 , and recoveries ranging from 80.20 % to 109.00 %, allowing for real-time quantitative monitoring of Sudan I. Significance This study employs hollow MOFs as support materials for in-situ growth of the imprinting layer, ensuring high adsorption capability and rapid binding. The successful implementation of two detection modes provides a comprehensive solution from laboratory precision to field application. Particularly, the portable sensing system enables real-time and on-site quantitative monitoring. This work exhibits the significant potential for the high-performance chemical sensing and point-of-care detection of food contaminants.

A robust and multi-functional nanocomposites with “soft and hard” nanodomains against harsh environments

Feng Gao,Lina Song,Zheming Tong,Taijiang Gui,Weiwei Cong,Kai Zhang,Xuri Wu,Quan Liu,Yongyuan Ren,Xiaoli Zhan,Qinghua Zhang

Due to their exceptional anti-adsorption efficacy against a variety of contaminants, superhydrophobic materials have received extensive interest. However, the most of them continue to suffer from mechanical fragility and low chemical stability, which severely restrict their practical applicability. Here, hierarchical structure of polymer/inorganic (HSMP) nanocomposites (NCPs) with dual crosslinking and low surface energy are designed and prepared by ultraviolet-induced polymerization strategy. Owing to the existence of crosslinking structure reduces the deformation and swelling caused by the interaction between poly(dimethysiloxane) (PDMS) and organic solvents, while the strong adhesion to substrate. The hybrid NCPs exhibit excellent superhydrophobicity and mechanical durability after 630 cycles sandpaper scratch and 1000 cycles bending. In addition, the NCPs also possessed high chemical stability under various thermal/solvent environments. Meanwhile, with the excellent flexibility and their remarkable gap between water and oil wettability, the oil/water separation studies of HSMP NCPs demonstrated over 95% separation efficiency after 50 cycles. Crucially, the produced NCPs exhibited remarkable anti-fouling properties, making them difficult to pollute in exposure conditions, which is crucial for sustainable applications.

Influence of host–guest interactions on analytical performance of direct analysis in real-time mass spectrometry

Liu Min,Wang Simin,Ge Wuxia,Bi Wentao,Chen David Da Yong

To systematically study the influence of host–guest interactions on the analytical performance of direct analysis in real time mass spectrometry (DART-MS), the interactions between cyclodextrins (CDs) and different Sudan dyes were investigated. The results showed that the host–guest interaction between CDs and Sudan dyes did not affect qualitative analysis of the target compounds, but led to a lower signal intensity for Sudan dyes, thus affecting quantitative analysis of the target compounds. The stronger the host–guest interaction, the weaker the signal intensity of target compound on DART-MS. The results also show that both in solution and in solid-phase microextraction (SPME), the addition of organic solvents can weaken the host–guest interaction between CDs and Sudan dyes, thus improving the signal intensity in DART-MS. In SPME, adding organic solvents has a certain practical value and can improve the efficiency of Sudan dye analysis. This study suggests that appropriate sample pretreatment is needed to weaken noncovalent interactions prior to DART-MS analysis to obtain more accurate quantitative results. The data provide some insight into the effects of other noncovalent interactions on the efficiency of DART-MS as an analytical tool, as well as the potential to study intermolecular interactions with DART-MS. Graphical Abstract

Multimaterial Three-Dimensional Printing of Ultraviolet-Curable Ionic Conductive Elastomers with Diverse Polymers for Multifunctional Flexible Electronics

Xiangnan He,Jianxiang Cheng,Zhenqing Li,Haitao Ye,Xinfeng Wei,Honggeng Li,Rong Wang,Yuan-Fang Zhang,Hui Ying Yang,Chuanfei Guo,Qi Ge

Ionic conductive elastomers (ICEs) are emerging stretchable and ionic conductive materials that are solvent-free and thus demonstrate excellent thermal stability. Three-dimensional (3D) printing that creates complex 3D structures in free forms is considered as an ideal approach to manufacture sophisticated ICE-based devices. However, the current technologies constrain 3D printed ICE structures in a single material, which greatly limits functionality and performance of ICE-based devices and machines. Here, we report a digital light processing (DLP)-based multimaterial 3D printing capability to seemly integrate ultraviolet-curable ICE (UV-ICE) with nonconductive materials to create ionic flexible electronic devices in 3D forms with enhanced performance. This unique capability allows us to readily manufacture various 3D flexible electronic devices. To demonstrate this, we printed UV-ICE circuits into polymer substrates with different mechanical properties to create resistive strain and force sensors; we printed flexible capacitive sensors with high sensitivity (2 kPa–1) and a wide range of measured pressures (from 5 Pa to 550 kPa) by creating a complex microstructure in the dielectric layer; we even realized ionic conductor-activated four-dimensional (4D) printing by printing a UV-ICE circuit into a shape memory polymer substrate. The proposed approach paves a new efficient way to realize multifunctional flexible devices and machines by bonding ICEs with other polymers in 3D forms.

Filter paper-based colorimetric analysis: An instrument-free strategy for semiquantitative naked-eye detection of food colorants

Shuangshou Wang,Lu Zhang,Qiwen Jin,Zhongqiu Xu,Jiayi Zhao,Yuwen Ding,Wenzhi Li,Peng Lin,Jing Gu,Qi Zhang,Yang Chen,Hongmei Chen,Tingxuan Yan

A filter paper-based colorimetric strategy for instrument-independent visual detection of artificial food colorants (FCs) was developed in this study. Indicator papers were prepared via the one-step polycondensation of silane coupling agents onto glass microfiber filter papers, and colorimetric cards with a fine one-to-one correspondence between their colors and FCs concentrations were straightforward obtained by the extraction of FCs with indicator papers by virtue of electrostatic interaction and hydrophobic effect. Filter papers post-modified via such a simple way were proved to be of improved binding class selectivity and colorimetric sensitivity, allowing for in-situ colorimetric assay of FCs in an unprecedently wide range of applicable pH (1.0–12.0) with high reliability and fine versatility. Finally, the semiquantitative naked-eye determination of FCs (Allura red, brilliant blue and sunset yellow) in real-world drink samples was experimentally confirmed to be feasible by comparison with the findings of UV–vis absorption spectra, HPLC and mass spectra.

A simple sensing platform based on a 1T@2H-MoS2/cMWCNTs composite modified electrode for ultrasensitive detection of illegal Sudan I dye in food samples

Qiaoling Wu,Chun Ji,Lingli Zhang,Qili Shi,Yuangen Wu,Han Tao

The work presented here describes a highly sensitive and simple electrochemical sensor for the detection of Sudan I dye based on a nanocomposite made of MoS2 heterogeneous nanosheets (1T@2H-MoS2) and carboxylated carbon nanotubes (cMWCNTs) (1T@2H-MoS2/cMWCNTs). XPS results indicate that the content of 1T phase MoS2 was estimated to be 72% in 1T@2H-MoS2. Electron microscopy results show that the tubular cMWCNTs are uniformly interwoven in MoS2 nanosheets to form a three-dimensional network structure. Due to the synergistic electrocatalytic ability and high electroactive surface area, the 1T@2H-MoS2/cMWCNTs modified electrode demonstrated excellent analytical performance for Sudan I, including simple operation, good stability and a wide linear range from 5.00 × 10−9 to 2.00 × 10−6 mol L−1 and 2.00 × 10−6 to 1.00 × 10−4 mol L−1 with an ultra-low detection limit of 1.56 × 10−9 mol L−1. The recoveries of Sudan I from spiked real samples (chilli powder and ketchup) were in the range of 95.60% to 106.10% with low RSD (<5%), indicating that the 1T@2H-MoS2/cMWCNTs modified electrode is a promising tool for the analysis of illegal Sudan I in food samples.

Encoding CsPbX3 perovskite quantum dots with different colors in molecularly imprinted polymers as fluorescent probes for the quantitative detection of Sudan I in food matrices

Jinxing He,Lu Yu,Yandu Jiang,Lei Lü,Zhonghui Han,Xiaolei Zhao,Zhixiang Xu

All-inorganic cesium lead halides (CsPbX 3 , X  = Cl, Br, I) perovskite quantum dots (PQDs) have attracted extensive research attention due to their unique optical properties. However, their instability and sensitivity to air and moisture hinder further use in fluorescent sensing applications. In this work, the construction and application of PQDs encoded molecularly imprinted polymers (MIPs-CsPbX 3 ) for Sudan I detection were proposed. After being encoded the PQDs, the obtained MIPs-CsPbX 3 microspheres exhibited high stability for the external environment, remarkable bright fluorescence, and specific recognition for Sudan I. The fluorescent intensity of the MIPs-CsPbX 3 microspheres was obviously quenched upon loading Sudan I, and good linear responses in the range of 0.5–150 µg L −1 , limit of detection of 0.3 µg L −1 , and good recoveries of 95.27 % to 105.96 % in spiked samples were obtained. The developed fluorescent probe provided a selective and sensitive quantified method for Sudan I detection in food matrices.

Novel Cu2+-based immobilized metal affinity magnetic nanoparticles for fast magnetic solid-phase extraction of trace Sudan dyes in food samples

Wei Zhou,Xin Wang,Youping Liu,Weikang Zhang,Xin Di

A novel type of Cu 2+ -based immobilized metal affinity magnetic nanoparticles (MHNTs@PDA@Cu 2+ ) was designed and synthesized by a facile and green strategy, and served as an adsorbent for magnetic solid-phase extraction (MSPE) of trace Sudan dyes in foodstuffs. Owing to π-π stacking, hydrogen bonding, hydrophobic and Cu 2+ -azo coordination, MHNTs@PDA@Cu 2+ possesses superior affinity and very fast adsorption capability to Sudan dyes (adsorption time of 1 min). The main parameters influencing the extraction efficiency of MSPE were investigated and optimized. By coupling MHNTs@PDA@Cu 2+ -based MSPE with HPLC-UV, a simple, fast and sensitive method for the determination of trace Sudan dyes in food samples were developed. Good linearity (R 2  ≥ 0.9937) and low limits of detection (0.06–0.10 μg L −1 ) were obtained. The method was successfully applied to determine Sudan dyes in juice, soy sauce and red wine, and the recoveries for the spiked samples ranged from 78.1% to 112.4% with RSD less than 9.0%.

Single-side etching for on-demand and versatile liquid diodes with opposite wettability in multiple systems

Wanshun Deng,Gang Wang,Zhixiang Zeng,Tianhui Ren

To achieve smart control of liquid penetration, liquid diodes have been widely studied in the recent years. However, most liquid diodes can only achieve opposite wettability in one or two systems, resulting in the loss of unidirectional liquid transportation property after they are wetted by immiscible liquids. This shortcoming will highly restrain the application areas of liquid diodes. Herein, a two-step single-side etching strategy have been adopted to develop opposite wettability on reverse sides of single-layered meshes. Opposite wettability forms not only in air but also under various liquids such as water and oil to realize unidirectional liquid penetration in these systems. More importantly, varied thickness of lyophobic layer was found to be crucial in liquid transportation in different systems, which was further demonstrated by the analysis of Laplace pressure on various meshes. Besides, the obtained liquid diodes were also competent in fog collection, liquid capture and oil/water separation, exhibiting great versatility. Thus, our findings not only propose on-demand and versatile liquid diodes but can also enlighten further study in smart valves in different systems.

Interactive and synergistic behaviours of multiple heterogeneous microrobots

Shilu Zhu,Weijie Zheng,Jian Wang,Xingmiao Fang,Lijiu Zhang,Fuzhou Niu,Ying Wang,Tingting Luo,Guangli Liu,Runhuai Yang

Microrobots have been extensively studied for biomedical applications, and significant innovations and advances have been made in diverse aspects of the field. However, most studies have been based on individual microrobots with limited capabilities, constraining their scalability of functions for practical use. Here, we demonstrate the interactive and synergistic behaviours of multiple microrobots that are heterogeneous or incompletely homogeneous. A frequency-response theory is proposed where in a certain frequency range of an external rotating magnetic field (RMF), microrobots with dispersed and linearly aligned magnetic nanoparticles (MNPs) would exhibit similar and different behaviour, respectively. These microrobots rotate following the rotation of the external field, and such complete rotational motion is interrupted when the frequency exceeds a certain value, called the critical frequency (cf), but such behaviour is more prominent in microrobots with linear MNPs. Upon further investigating the effect of various parameters on the cf of the microrobots during the fabrication process, we find that heterogeneous microrobots with specific cf values can be customized. In addition, experiments and simulations are combined to show the hydrodynamic behaviours around the rotating microrobots at different frequencies. Based on these findings, the interactive and synergistic behaviours of multiple microrobots are presented, which suggests great potential for the independent execution of multiple tasks or the synergistic performance of complex tasks and is significant for the future development of interactive synergistic microrobots in the biomedical field.

Simultaneous and rapid screening and determination of twelve azo dyes illegally added into food products by using chemometrics-assisted HPLC-DAD strategy

Ming-Yue Dong,Hai-Long Wu,Wan-Jun Long,Tong Wang,Ru-Qin Yu

Edible colorants, as an essential external condition of food products, can increase people’s appetite. Some businesses have used some cheap and illegal dyes instead of edible colorants to gain benefits. It not only deceives consumers, but also seriously endangers their health. In this work, two chemometric algorithms assisted high-performance liquid chromatography with diode array detection (HPLC-DAD) were proposed for screening and quantifying twelve azo dyes illegally added into different food products. All analytes were successfully eluted within 6.5 min. With the aid of the prominent “second-order advantage” of the chemometric algorithms, the overlapping peaks and unknown interferences were solved. The spiked average recoveries obtained by alternating trilinear decomposition (ATLD) and multivariate curve resolution-alternating least squares (MCR-ALS) were 82.8–111.5% with standard deviation (SD) less than 6.5% and 78.7–122.6% with SD less than 18.7%, respectively. The limits of detection were 0.01–2.56 mg kg −1 and 0.01–2.95 mg kg −1 , respectively. The results indicated that two algorithms had practical value for the simultaneous and rapid screening and determination of azo dyes in food products. Compared with other methods based on HPLC, the proposed method could flexibly handle different interferences, and had the advantages of high efficiency, simple operation and being environmentally friendly.

Synthesis, characterization and properties of novel nonionic hydrocarbon/fluorocarbon hybrid surfactants containing a short fluoroalkyl chain

Yutang Zhou,Yichao Shen,Liangjie Shi,Yong Jin,Shuangquan Lai,Yujia Tang