查找使用阿拉丁产品的科研文献

Surface programmed bacteria as photo-controlled NO generator for tumor immunological and gas therapy

Baizhu Chen,Xiaoge Zhang,Lili Cheng,Xiaomei Chen,Junjie Tang,Peng Zhang,Chen Wang,Jie Liu

The use of bacteria as living vehicles has attracted increasing attentions in tumor therapy field. The combination of functional materials with bacteria dramatically facilitates the antitumor effect. Here, we presented a rationally designed living system formed by programmed Escherichia Coli MG1655 cells (Ec) and black phosphorus (BP) nanoparticles (NPs). The bacteria were genetically engineered to express tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), via an outer membrane YiaT protein (Ec-T). The Ec-T cells were associated with BP NPs on their surface to acquire [email protected] The designed living system could transfer the photoelectrons produced by BP NPs after laser irradiation and triggered the reductive metabolism of nitrate to nitric oxide for the in situ release at tumor sites, facilitating the therapeutic efficacy and the polarization of tumor associated macrophages to M1 phenotype. Meanwhile, the generation of reactive oxygen species induced the immunogenic cell death to further improve the antitumor efficacy. Additionally, the living system enhanced the immunological effect by promoting the apoptosis of tumor cells, activating the effect of T lymphocytes and releasing the pro-inflammatory cytokines. The integration of BP NPs, MG1655 cells and TRAIL led to an effective tumor therapy. Our work established an approach for the multifunctional antitumor living therapy.

Designing ultrathin Ag-embedded g-C3N4 nanocomposites for enhanced disinfection performance under visible light

Jinyan Du,Na Xu,Pingchuan Yuan,Qin Shu,Chaofeng Wang,Qidi Xu,Ping Zhang,Shujuan Zhuo,Changqing Zhu

Using ammonium chloride (NH 4 Cl) as a gas template, we conveniently fabricated ultrathin two-dimensional layered silver-embedded graphitic carbon nitride nanosheets (AgCNS) by melamine blowing method with triazine groups of pristine graphite carbon nitride. Compared with bulk g-C 3 N 4 (BCN) and g-C 3 N 4 nanosheets (CNS), the antibacterial activity of the optimized AgCNS-5 at a minimum inhibitory concentration (MIC) of 40 ppm against Escherichia coli ( E. coli ) was significantly enhanced. Under visible-light irradiation, E. coli could be completely killed by 100 µg·mL −1 of AgCNS-5 within 30 min. The mechanism of enhanced antibacterial activity was systematically investigated by ultraviolet-visible diffuse reflectance spectra (UV-vis DRS), photoluminescence spectra (PL), electrochemical impedance spectroscopy (EIS), and photogenerated current densities. Surface plasmonic resonance (SPR) of Ag nanoparticles (NPs) with g-C 3 N 4 was found to lead to an enhancement of visible light absorption and an acceleration of photo-induced electron-hole migration/separation, which is responsible for the enhanced photocatalytic bactericidal performance. Through trapping experiments and electron spin resonance spectroscopy (ESR) techniques, the bactericidal mechanism was revealed that the species of •O 2 − and •OH play important roles in antibacterial process. Considering the facile preparation and excellent performance, AgCNS-5 may be a promising and competitive visible-light-driven candidate toward sterilizing agent.

Dual-responsive multilayer beads with zero leakage and controlled release triggered by near-infrared light

Lerong Liu,Weizheng Song,Wan Zheng,Feihu Li,Hanlin Lv,Yuhang Wang,Yanjun Chen,Yifeng Wang

Multilayer beads made from biomacromolecules are useful for encapsulating, protecting, and delivering active ingredients such as drugs, dyes, and proteins. However, their encapsulated cargos are allowed to diffuse slowly out into the surrounding solvent during storage. This study describes a “smart” multilayer bead that can achieve zero leakage for encapsulated materials during storage and controlled release after triggered by near-infrared (NIR) light. The innermost layer of the multilayer bead containing Fe 3 O 4 magnetic nanoparticles is prepared based on the thermal-responsive sol-gel transition of agar, which offers magnetic responsiveness to the bead. The middle layer of the bead embedding gold nanorods (Au NRs) is produced by the ionic crosslinking between alginate and terbium ions. Moreover, encapsulated materials (drugs, dyes, and agrochemicals) are loaded in the middle layer. The outermost layer of the bead, a paraffin-wax shell, is formed at 75 ℃ through the phase transition of paraffin wax . Because of the protection of the paraffin-wax shell, the encapsulated materials present zero leakage when the multilayer bead is placed in aqueous solutions for at least six weeks. Under the irradiation of 808 nm NIR light for 1 min, the multilayer bead is heated up to 50 ℃ by the photothermal effect of Au NRs in the middle layer, which triggers the melting of the paraffin-wax shell. Then, the controlled release of the encapsulated materials can be achieved by the rest of the bead. Furthermore, the bead can be recycled after the release due to its magnetic responsiveness. Consequently, the multilayer bead is a novel, green and economical candidate for diverse applications, especially for the encapsulation and controlled release of hydrophilic materials in bio-related applications.

Surface hydrolysis-anchored eugenol self-polishing marine antifouling coating

Jianang Sha,Xin liu,Rongrong Chen,Jing Yu,Qi Liu,Jingyuan Liu,Jiahui Zhu,Peili Liu,Rumin Li,Jun Wang

Traditional self-polishing antifouling coatings kill surface organisms by releasing toxic substances, which are damaging to the ecosystem. As a natural antimicrobial substance, eugenol is environmentally friendly and has been proven by different research teams to be effective in enhancing the anti-fouling effect of coatings in the real sea. While in these previous research works, the eugenol was released directly into the seawater thus cannot further serve as surface antifouling effect, leading to a limited antifouling effect of the coating. In this work, the quaternary ammonium component was introduced into the butyl ester-based resin - poly (eugenol methacrylate - acryloyloxyethyltrimethyl ammonium chloride - hexafluorobutyl methacrylate - methyl methacrylate - butyl methacrylate - ethylene glycol methyl ether acrylate) (EMQFP) coating for the first time by simple one-step free radical polymerization method. On the one hand, the eugenol produced by hydrolysis is anchored to the quaternary ammonium on the coating surface for a period of time due to the cationic-π interaction, instead of being released into seawater immediately after hydrolysis, thus increasing the utilization rate of eugenol; on the other hand, the negatively charged carboxylate groups generated after hydrolysis in the coating are mutually attracted to quaternary ammonium through electrostatic effect, so the resin chain segment conformation on the coating surface adjusted to produce zwitterionic-like structure, and the hydration of zwitterionic inhibits primary fouling adhesion.

Synthesis of high strength agar and its water plugging application in enhanced oil recovery

Kaiping Tian,Wanfen Pu,Shuai Zhao

Metal–Organic Frameworks in Microfluidics Enable Fast Encapsulation/Extraction of DNA for Automated and Integrated Data Storage

Cuiping Mao,Shuchen Wang,Jiankai Li,Zhuowei Feng,Tong Zhang,Rui Wang,Chunhai Fan,Xingyu Jiang

DNA as an exceptional data storage medium offers high information density. However, DNA storage requires specialized equipment and tightly controlled environments for storage. Fast encapsulation within minutes for enhanced DNA stability to do away with specialized equipment and fast DNA extraction remain a challenge. Here, we report a DNA microlibrary that can be encapsulated by metal–organic frameworks (MOFs) within 10 min and extracted (5 min) in a single microfluidic chip for automated and integrated DNA-based data storage. The DNA microlibrary@MOFs enhances the stability of data-encoded DNA against harsh environments. The encoded information can be read out perfectly after accelerated aging, equivalent to being readable after 10 years of storage at 25 °C, 50% relative humidity, and 10 000 lx sunlight radiation. Moreover, the library enables fast retrieval of target data via flow cytometry and can be reproduced after each access.

Selective enrichment of Rutin in sunscreen by boronate affinity molecularly imprinted polymer prior to determination by high performance liquid chromatography

Jinyue Chai,Xue Chen,Chengcheng Jin,Fang Chai,Miaomiao Tian

In this study, AgCl was used as the carrier matrix, TiO 2 was introduced on the substrate surface, carboxyphenylboronic acid (CPBA) was used as the boronate affinity functional monomer , and Rutin (RT) as template to prepare molecular imprinted adsorbent AgCl@TiO 2 @B-MIPs (B-MIPs). The effects of synthesis conditions, solid-phase extraction (SPE) conditions, selectivity, competitiveness, reproducibility, and reusability were evaluated in detail. Under the optimum adsorption conditions, the maximum adsorption capacity is 31.70 mg g −1 . The utility of B-MIPs as a SPE adsorbent for RT was supported by an abundance of pore structure, as well as boric acid affinity sites that facilitate rapid binding of adsorbents to templates. The linear range is 0.05–50 mg L −1 , and the limit of detection (LOD) is 0.023 mg L −1 . The method was used for the determination of RT in sunscreen and isolation cream by high-performance liquid chromatography (HPLC). The target analytic recoveries are in the range of 84.7–98.0% (relative standard deviation is less than 2.4%, n  = 3). Furthermore, this work provides a potential possibility to detect other cis -diol containing analytes in the complex matrix.

A conductive hydrogel based on nature polymer agar with self-healing ability and stretchability for flexible sensors

Zhen Nie,Kelin Peng,Lizhi Lin,Jueying Yang,Zhekun Cheng,Qiang Gan,Yu Chen,Changgen Feng

Conductive hydrogels (CHs) have drawn wide attention from the field of flexible sensor for their similarities to tissues, excellent flexibility and good electrical conductivity. However, most of the reported hydrogel-based flexible sensors display the disadvantages of poor tensile strength, low sensitivity and insufficient stability, and most of them are prepared with non-degradable synthetic polymers, which have greatly limited their application. To solve these problems, in this work, we have constructed an agar-based dynamic double cross-linked CH by the dynamic crosslinking between agar and borax via borate bonds and the hydrogen bonds between agar chains. The CH exhibits excellent electrical conductivities, tensile properties and self-healing abilities. A novel two-dimensional material, MXene nanosheet, was introduced to further improve the mechanical properties and ionic conductivity of the CH with its high ionic conductivity and ability to form hydrogen bonds with agar. The obtained Agar/Borax/MXene CH displays the excellent strength and elongation of 129 kPa and 105.1 % and the satisfying ionic conductivity of 8.14 × 10 −2 S/cm. The flexible sensor assembled with Agar/Borax hydrogel with 0.15 wt% MXene exhibits a wide strain detection range from 0 to 100 %, high sensitivity (GF≈1.520) and good stability. Our work has provided a novel strategy for the construction of green flexible sensors with good mechanical properties and high sensitivity.

Self-Adhesive and Conductive Dual-Network Polyacrylamide Hydrogels Reinforced by Aminated Lignin, Dopamine, and Biomass Carbon Aerogel for Ultrasensitive Pressure Sensor

Changzhou Chen,Na Zheng,Weixin Wu,Mengqi Tang,Wenyao Feng,Wei Zhang,Xiangyu Li,Yan Jiang,Jinhui Pang,Douyong Min,Lianhua Fu

Conductive hydrogels have attracted extensive interest owing to its potential in soft robotics, electronic skin, and human monitoring. However, insufficient mechanical properties, lower adhesivity, and unsatisfactory conductivity seriously hinder potential applications in this emerging field. Herein, a highly elastic conductive hydrogel with a combination of favorable mechanical properties, self-adhesiveness, and excellent electrical performance was achieved by the synergistic effect of aminated lignin (AL), polydopamine (PDA), polyacrylamide (PAM) chains, and biomass carbon aerogel (C-SPF). In detail, AL was applied to induce slow oxidative polymerization of DA for preparing the sticky hydrogel containing PDA. Then, C-SPF carbon aerogel was used as a matrix to construct a dual-network structured composite hydrogel by combining with the hydrogels derived from PDA, AL, and PAM. The as-prepared conductive hydrogel displayed excellent mechanical performance, strong adhesive strength, and repeatable adhesivity. The prepared hydrogel-based pressure sensor possessed fast response (0.6 s loading and 0.8 s unloading stress time), high response (maximum RCR = 1.8 × 104), wide working pressure range (from 0 to 240.0 kPa), and excellent durability (stable 500 compression cycles with 30% deformation). In addition, the prepared sensor also displayed ultrahigh sensitivity (170 kPa–1), which was near 4 orders of magnitude higher than the conventional lignin-modified PAM hydrogels. The multiple interactions between hydrogel components and the mechanical properties of hydrogel were also verified by molecular dynamics investigation. Moreover, the excellent cytocompatibility and antibacterial activity of this composite hydrogel ensured high potential in various applications such as human/machine interaction, artificial intelligence, personal healthcare, and wearable devices.

Multifunctional ZnFeO4-Based Antibiotic Cross-Linked Nanoplatform for Magnetically Targeted Treatment of Microbial Biofilms

Xingyue Yang,He Ren,Jiexin Li,Boyang Sun,Di Lu,Shuying Li,Yumiao Zhang

During the infections of wounds or medical device surfaces, bacteria such as Pseudomonas aeruginosa are prone to forming biofilms which prevent the penetration of antimicrobial agents. Herein, a combined therapy using bactericidal nano-micelles Ce6-ZnFeO4@ABCsi-micelles was developed that employed colistin cross-linked Pluronic micelles as a carrier, with the magnetic metal oxide ZnFeO4 and photosensitizer dihydroporphyrin (Ce6) encapsulated in the core of micelles. Driven by an external magnetic field, the nano-micelles could penetrate the external barrier of the biofilm. Reactive oxygen species (ROS) generated by the photosensitizer Ce6 disrupted the barrier of the biofilm, which facilitated the distribution of the Ce6 and colistin antibiotics into the biofilm, realizing a 99.5% clearance rate of bacteria. Using such a combination of chemotherapy and photodynamic therapy, Ce6-ZnFeO4@ABCsi-micelles could clear wound infection in a murine abscess model, owing to the targeted driving effect of the external magnetic field, along with the chemotherapeutic effect of colistin and the photodynamic effect of Ce6. This design provides an effective targeted therapeutic strategy to address biofilm infections.

Impacts of Non-Lethal High-Temperature Stress on the Development and Reproductive Organs of Bradysia odoriphaga

Jingrong Hu,Rudoviko Galileya Medison,Seng Zhang,Peifang Ma,Caihua Shi

Simple SummaryBradysia odoriphagais a soil-dwelling insect native to China, and its preferred host is Chinese chives. In this study, non-lethal high-temperature as an important limiting factor to affect the population and development ofB. odoriphagawas assessed. Meanwhile, the physiological mechanism on non-lethal high-temperature to reduce the population was also identified. These would lay a key theoretical foundation for the future development of high-temperature products for environment friendly pest control strategies.AbstractBradysia odoriphagais an agricultural pest in China’s vegetable industry. In this study, pupae and adults were exposed to various non-lethal high-temperatures. The results demonstrated a decreased rate of eclosion once the pupae were exposed to temperatures exceeding 37 °C for 1 h. No effect on the lifespan of unmated female adults was observed after exposure to temperature stress, while unmated male adult lifespan decreased (>37 °C for 2 h). The size of the testis and ovaries for unmated male and female adults decreased, as did the fecundity and egg hatching rate for mated females. Compared with the control group (25 °C), the testis size of unmated male adults decreased after high-temperature stress followed by recovery at 25 °C for 1 h, though the size of the ovaries of female adults did not change. Additionally, the size of the testis and ovaries for unmated male and female adults decreased following high-temperature stress and 24 h of recovery at 25 °C. High temperatures affected males more than females; 37 °C is the critical temperature to control the population ofB. odoriphaga. These results lay the foundation for the future development of environmentally friendly high-temperature prevention and pest-control strategies.Keywords:Allium tuberosum;chive gnats;emergence;fertility;sublethal

Controllable synthesis of a sponge-like Z-scheme N,S-CQDs/Bi2MoO6@TiO2 film with enhanced photocatalytic and antimicrobial activity under visible/NIR light irradiation

Yanning Qu,Xinyang Li,Hengli Zhang,Renliang Huang,Wei Qi,Rongxin Su,Zhimin He

Multifunctional photocatalytic surfaces for pollutant degradation and antimicrobial application are often in high demand, however they confront many challenges in charge transfer and light capture ability. In this work, a sponge-like N,S-CQDs/Bi 2 MoO 6 @TiO 2 film was constructed via hydrothermal technique aiming to solve above problems. As a result, the ternary film showed enhanced photocatalytic efficiency under visible and near-infrared (NIR) light, in which 85.8% and 44.6% of ciprofloxacin (CIP) were degraded after 240 min irradiation with visible and NIR light, respectively. Moreover, the composite film effectively realized photocatalytic sterilization of gram-positive B. subtilis and gram-negative E. coli under visible light irradiation. The bacterial colony decreased significantly from 7.56-log to 1-log cfu/mL after adding the ternary film within 1.5 h. The enhanced photocatalytic efficiency was closely related to both introduction of surface-functional N,S-CQDs and the construction of N,S-CQDs/Bi 2 MoO 6 @TiO 2 Z-scheme system, in which the transfer efficiency of photoinduced carriers and the light absorption property were significantly improved. We consider that the N,S-CQDs/Bi 2 MoO 6 @TiO 2 film is promising for the degradation of refractory pollutants and antimicrobial application under visible/NIR light irradiation. The relatively convenient recycling property and excellent photocatalytic performance of the N,S-CQDs/Bi 2 MoO 6 @TiO 2 film are beneficial for industrial applications.