共轭聚合物生物电子体系研究进展

共轭聚合物类的有机共轭分子由于其特殊的电子离域效应,具有优异的光电性能.另外该类材料骨架结构丰富、能带可调、易于修饰与制备,使得这类材料除了在发光二极管、场效应晶体管和光伏电池等方面有广泛的研究和应用之外,在生物成像、生物传感、疾病诊断和治疗中也发挥了重要作用.本文综述了近年来基于水溶性共轭聚合物的生物电子体系构建和应用,主要介绍了水溶性共轭聚合物在光合作用、生物燃料电池、生物光伏、生物电子催化等方面的最新研究进展.

Efficient purification of Al_(30) by organic complexation method

A method was developed for preparing high purity Al30O8(OH)56(H2O)_(24)^(18)+(Al30) through elimination of impurities by complexation.Polyaluminum chloride II(PAC_(30))with Al_(c )content of 75%was adopted as the source of Al_(30).The PAC_(30)was prepared under conditions of total aluminum concentration 0.1 mol/L and OH^-/Al ratio 2.2 to obtain the highest content of Al_(30).A precipitation/metathesis method,organic solvent precipitation method and organic complexation method were examined to separate and purify Al_(30).It was found that only by the organic complexation method could high purity Al_(30)products be obtained in large yield economically.In the experiments,benzoic acid was used as the coordinating reagent to decompose the main impurity AlO_4Al_(12)(OH)_(24)(H_2O)_(12)^(7+)(Al_(13)),and the Al_(30)product could be obtained by precipitation and metathesis operations.It was noteworthy that the decomposition of impurities by benzoic acid could be completed in 2 hr.The Al_(30)product was characterized by Ferron assay,^(27)Al-NMR,SEM,XRD and TGA.The results showed that the purity of the Al_(30)product could exceed 92%.

Oligo(p-phenylenevinylene)-rhodium complex as intracellular catalyst for enhancing biosynthesis of polyhydroxybutyrate biomaterials

Microbial synthesis utilizes sustainable resources to produce valuable chemicals,as a potential alternative to petroleum-based chemical industry.Although metabolic engineering is an efficient method to enhance the biosynthesis efficacy of microorganisms,it requires complicated biological procedures.Herein,we report a facile intracellular catalysis system for augmenting the production of bio-based material in microorganism.Covalent linking of oligo(p-phenylenevinylene)(OPV)and cyclopentadienyl rhodium(Ⅲ)bipyridine offers intracellular metal catalyst(OPV-Rh).The OPV-Rh complex displayed certain resistance to toxic biomolecules,which guaranteed its catalytic activity in complicated biological systems.With uptake by Gramnegative bacterium Ralstonia eutropha H16(R.eutropha H16),the OPV-Rh complex promotes the transformation of intracellular NADP+to NADPH,which further enhances the biosynthesis of polyhydroxybutyrate(PHB)by this microorganism.This work demonstrates that synthetic metal catalyst can be employed for regulating microbial biosynthesis intracellularly.

A hybrid nano-assembly with synergistically promoting photothermal and catalytic radical activity for antibacterial therapy

It is of great significance to develop effective antibacterial agents and methods to combat drug resistant bacterial infections due to its increasing threaten to human health and the ineffectiveness of antibiotics.Herein,a multifunctional hybrid nano-assembly(M1-Fe NPs)based on conjugated oligomer and ferrous ion was engineered with favorable bactericidal activity for synergetic antibacterial therapy.The chelation of ferrous ion not only enhances the photothermal conversion efficiency of M1 but also endows the nano-assembly with catalytic capability of transferring H_(2)O_(2) into stronger oxidant hydroxyl radicals(·OH).Meanwhile,the generated heat can further promote the Fenton reaction activity.By generating cytotoxic heat and oxidative·OH,M1-Fe NPs can effectively kill Staphylococcus aureus in vitro and in vivo with the aid of low dosage of H_(2)O_(2).The work provides a new multifunctional platform for combinational drug resistant antibacterial therapy and even antitumor therapy.

Nucleic acids analysis

Nucleic acids are natural biopolymers of nucleotides that store, encode, transmit and express genetic information, which play central roles in diverse cellular events and diseases in living things. The analysis of nucleic acids and nucleic acids-based analysis have been widely applied in biological studies, clinical diagnosis, environmental analysis, food safety and forensic analysis.During the past decades, the field of nucleic acids analysis has been rapidly advancing with many technological breakthroughs.In this review, we focus on the methods developed for analyzing nucleic acids, nucleic acids-based analysis, device for nucleic acids analysis, and applications of nucleic acids analysis. The representative strategies for the development of new nucleic acids analysis in this field are summarized, and key advantages and possible limitations are discussed. Finally, a brief perspective on existing challenges and further research development is provided.

覆尘滤袋综合渗透率的分形求解

基于分形理论计算滤袋及滤饼构成的综合渗透率,描述其渗流特性。结合滤饼扫描电镜实验与图像处理技术分析滤饼孔隙结构;利用改进的毛细管模型近似模拟滤饼孔隙通道,根据流体动力学原理得到了滤饼渗透率的分形表达式,并由达西定律计算得覆尘滤袋综合渗透率,并用其对袋式除尘器流场压力分布进行数值模拟。结果表明,滤饼孔隙结构具有自相似特点。覆尘滤袋综合渗透率为(1.615~4.784)×10^-12 m^2,模拟所得的滤袋内外压差与实验结果的相对误差小于26%。覆尘滤袋综合渗透率计算方法合理,可较好地描述复合多孔介质的渗流特性。

Design of antibacterial peptide-like conjugated molecule with broad spectrum antimicrobial ability

Increasing multidrug-resistant(MDR) superbugs emerge worldwide causing a public health crisis. Consequently, it is urgent to find new antibiotics with efficient broad-spectrum antimicrobial activity. By virtue of versatility in molecular design, a new peptide-like cell membrane-broken molecule, oligo-(7,7′-bifluoren-benzo[c][1,2,5]thiadiazole)(OFBT) possessing a conjugated backbone and eight pendant guanidyl moieties was designed and synthesized. OFBT exhibits favorable broad-spectrum of antimicrobial activity to pathogens including Gram-negative and Gram-positive bacteria, and fungi with the minimum inhibitory concentration(MIC)below 3.0 μM. Moreover, OFBT exhibits high selectivity for pathogens over human cells to make it a promising broad spectrum antimicrobial agent.

Cationic conjugated polymers for detection and inactivation of pathogens

Conjugated polymers(CPs) are referred to a kind of fluorescent polymer materials with delocalized π-conjugated backbones.For the last decades, cationic CPs(CCPs) have been widely used in biosensor, imaging and biomedical fields due to their good photophysical properties and solubility in water medium resulting from side chain modification with ionized moieties. In this mini-review, we mainly introduced the applications of CCPs in detection and inactivation of pathogen with typical examples, and also briefly discussed the relevant mechanisms. We hold the expectation that this mini-review can offer researchers a general reference and inspire them to construct new systems with high performances of pathogen detection and antimicrobial activity.

Living Bacteria-Mediated Aerobic Photoinduced Radical Polymerization for in Situ Bacterial Encapsulation and Differentiation

Conventional polymerizations mediated by living cells typically require synthetic transition-metal complexes or photoredox catalysts.Herein,we report an alternative photoinduced polymerization strategy for preparing functional polymer hydrogels through bacteria-initiated radical polymerization of acrylamides in ordinary culture media.Upon light irradiation under ambient conditions,polyacrylamides were obtained with molecular weights of over 150 kDa using various bacteria.

In Situ-Induced Multivalent Anticancer Drug Clusters in Cancer Cells for Enhancing Drug Efficacy

Increasing intracellular drug concentration is an effec-tive way for cancer chemotherapeutics to enhance efficacy and combat drug resistance.In this work,a series of anticancer drug conjugates were prepared by linking thiol-modified oligo(p-phenylene viny-lene)with paclitaxel,vincristine,teniposide,tamoxi-fen,doxorubicin,or podophyllotoxin(OPV-S-Drugs)through a Michael addition reaction.

Conjugated polymer nanoparticles as fluorescence switch for selective cell imaging

Fluorescence switch plays a vital role in bioelectronics and bioimaging.Herein,we presented a new kind of facile electrostatic complex nanoparticles(ECNs)for fluorescence switching in cells and marking of individual cell.The ECNs were prepared by mixing positively charged poly(6-(2-(thiophen-3-yl)ethoxy)hexyl trimethylammonium bromide)(PT)and negatively charged diarylethene sodium salt(DAECOONa).DAE-COONa is a photoswitchable molecule which can be transformed between the ring-closed fo rm and ring-open form under the irradiation of UV or visible light.The closed-form of DAE-COONa can efficie ntly quench the fluorescence of PT through intermolecular energy transfer,while the open form of DAE-COONa does not influence the emission of PT.Thus,the fluorescence of ECNs can be modulated by light irradiation,and the ECNs with good fluorescence switching performance have been employed for fluorescence imaging and individual cell lighting up process successfully.We demonstrate that the electrostatic complex strategy provides a facile method to construct fluorescence switch fo r selective cell marking and imaging applications.

Synthesis of amphiphilic poly(fluorene) derivatives for selective imaging of Staphylococcus aureus

Three amphiphilic poly(fluorene-co-phenylene) derivatives with different side chains(PFP-1, PFP-2, PFP-3) were designed and synthesized for exploring their detection and imaging of pathogens. Upon incubation with six kinds of different pathogens, it was found the three polymers could selectively interact with Staphylococcus aureus(S. aureus). Their selective imaging towards S. aureus were thus realized. The selective imaging towards S. aureus was also confirmed even under the blend of microbes. PFP-3 shows stronger fluorescence imaging signal than PFP-1 and PFP-2. Zeta potential and isothermal titration microcalorimetry(ITC) tests demonstrated that both electrostatic interactions and hydrophobic interactions played important roles in the binding between PFPs and pathogens. Thus, amphiphilic PFP-3 exhibits great potential for specific imaging of S. aureus in a simple and rapid manner.

High-performance fiber strain sensor of carbon nanotube/thermoplastic polyurethane@styrene butadiene styrene with a double percolated structure

In this work,a high-performance fiber strain sensor is fabricated by constructing a double percolated structure,consisting of carbon nanotube(CNT)/thermoplastic polyurethane(TPU)continuous phase and styrene butadiene styrene(SBS)phase,incompatible with TPU(CNT/TPU@SBS).Compared with other similar fiber strain sensor systems without double percolated structure,the CNT/TPU@SBS sensor achieves a lower percolation threshold(0.38 wt.%)and higher electrical conductivity.The conductivity of 1%-CNT/TPU@SBS(4.12×10^(-3) S·m^(-1))is two orders of magnitude higher than that of 1%-CNT/TPU(3.17×10^(-5) S·m^(-1))at the same CNT loading of 1 wt.%.Due to double percolated structure,the 1%-CNT/TPU@SBS sensor exhibits a wide strain detection range(0.2%-100%)and an ultra-high sensitivity(maximum gauge factor(GF)is 32411 at 100%strain).Besides,the 1%-CNT/TPU@SBS sensor shows a high linearity(R^(2)=0.97)at 0%-20%strain,relatively fast response time(214 ms),and stability(500 loading/unloading cycles).The designed sensor can efficiently monitor physiological signals and movements and identify load distribution after being woven into a sensor array,showing broad application prospects in wearable electronics.

Selective biocompatibility and responsive imaging property of cationic conjugated polyelectrolyte to cancer cells

Optical imaging, as an important molecular imaging modality, has emerged many attractions in studying the biological or molecular events both in cell level and living subject because of its high resolution and sensitivity, noninvasive manner and low cost. Herein, we bring novel insights into a water-soluble conjugated polyelectlyte by deeply studying its properties in cells. Poly（9, 9-bis（6＇-N,N,N-trimethylammonium hexyl）fluorene phenylene）（PFP）, a good biosensing material, was studied in this paper. The biocompatibility of PFP was investigated in different cells, and cell cycle analysis was carried out to explore the reasons of different biocompatibility of PFP to cells. After irradiation, fluorescence enhancement of blue emission and turn-on of long-wavelength emission of PFP in HepG2 cells was observed, which was first reported as far as we know. The differentiated biocompatibility of PFP and its particular imaging properties in cancer cells can help to guide the application of conjugated polymers in cells and provide a new dimension in designing sensitive and responsive imaging materials.

Prokaryotic expression and purification of fusion protein HSP70-EGFP and its application in the study of dendritic cells internalization antigen

To study the endocytic activity of dendritic cells(DCs)by obtaining fusion protein HSP70-EGFP as exogenous antigen and loading it with DCs derived from human peripheral blood.Fusion protein HSP70-EGFP was prokaryotically expressed,isolated and purified.DCs were isolated and cultured from human peripheral blood.The DCs were divided into 3 groups in the endocytic experiment.There were 106 DCs in each group.Group 1 and 2 were respectively incubated for 30 min.with HSP70-EGFP and EGFP.Group 3 was incubated with HSP70 for 30 min,and then incubated for 30 min.with HSP70-EGFP.Subsequently,3 groups were placed in an incubator at 37℃for 0.5,1,2 and 24 h.Flow cytometry(FCM)was adopted to detect the amount of DCs with EGFP inside.IL-12 Eli-spot was adopted to detect the amount of DCs which secreted IL-12.There were 5 types in the experiment:LPS,inactive LPS,HSP70-EGFP,EGFP and no antigen.Fusion protein HSP70-EGFP was successfully obtained and its molecular weight was 97000.It accounted for 35.32%of the total protein.Under irradiation of an ultraviolet lamp,the protein solution sent out viridescent fluorescence.The result detected by FCM indicated that after incubation for 0.5 h at 37℃,the positive rate in group 1 was 63%,while the other 2 groups were negative.After incubation for 1,2 and 24 h at 37℃,the positive rates in the 3 groups were above 80%.The IL-12 Eli-spot examination shows that with HSP70-EGFP being loaded,the amount of DCs secreting IL-12 was 134.09±31.78/10^(5)cells,a little lower than that of DCs with LPS loaded(with the average point of 156.36±15.73).There was no significant difference between the 2 groups(P<0.01).By contrast,both of them were significantly higher than inactive LPS-(33.78±1.40)/10^(5)cells and EGFP-loaded(23.13±4.57)/105 cells DC groups in the amount of DCs secreting IL-12(P<0.01).The results suggest that receptor-mediated phagocytosis plays a main role in the preliminary stage of DCs internalizing HSP70-EGFP.With increasing incubation time,pinocytosis begins to dominate.HSP70-EGFP may promote DCs to secret cell factor IL-12.

Conjugated polymer materials for detection and discrimination of pathogenic microorganisms:Guarantee of biosafety

Infectious disease outbreaks have seriously endangered global health owing to the scarcity of testing materials and techniques.Diversified materials and methods should be urgently developed for rapid detection and discrimination of pathogenic microorganisms.Conjugated polymer(CP)materials are macromolecular compounds comprising numerous covalently bonded luminescent units.They have excellent light-harvesting and optical signal amplification capabilities owing to the transmission of excitation energy along their backbone.In recent years,CP materials have aroused research enthusiasm in the biosensors field because of their outstanding optoelectronic properties.This brief manuscript provides an overall review of recent progress achieved in CP-based systems for pathogen sensing.

Corrigendum to<’Efficient purification of Al_(30) by organic complexation method’><[Journal of Environmental Sciences 80(2019)240-247]>30

The authors regret<the information of authors and affiliations“Libing Liu Qinxue Yang 2,3,Pin Wang 1,2,Feng Xiao 2,Ruyuan Jiao 2,Guangyu An 2,∗,Dongsheng Wang 2,∗1,2,1.University of Chinese Academy of Sciences,Beijing 100085,China 2.State Key Laboratory of Environmental Aquatic Chemistry,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China3.Faculty Materials Science and Chemistry,China University of Geosciences,Wuhan 430074,China”should be changed to“Libing Liu 1,2,Qinxue Yang 1,3,Pin Wang 1,2,Feng Xiao 1,Ruyuan Jiao 1,Guangyu An 1,∗,Dongsheng Wang 1,∗1.State Key Laboratory of Environmental Aquatic Chemistry,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China 2.University of Chinese Academy of Sciences,Beijing 100049,China 3.Faculty Materials Science and Chemistry,China University of Geosciences,Wuhan 430074,China”>.

天然来源的纳米类囊体应用于肿瘤的多模式治疗

多模式联合治疗已成为抗肿瘤的有效手段,但目前已报道的多模式肿瘤治疗试剂通常需要复杂的功能组分和繁琐的合成过程.因此,开发一种简单制备的天然来源多模式肿瘤治疗试剂仍然是一个挑战.本文从菠菜叶片中提取出了一种天然来源的、具有类酶性质的纳米类囊体用于肿瘤的多模式治疗.结果表明,纳米类囊体具有良好的光热转换和光敏化性质,可以有效杀伤4T1和MCF-7肿瘤细胞.同时,该材料还具有类过氧化物酶的性质,可以氧化分解过氧化氢产生羟基自由基从而诱导肿瘤细胞凋亡.因MCF-7肿瘤细胞内过量表达过氧化氢,该材料可实现对MCF-7肿瘤细胞的选择性杀伤.该纳米类囊体在细胞水平和活体小动物水平对肿瘤具有显著的治疗效果,且表现出良好的生物安全性.研究表明,该纳米类囊体具有光热转换、光敏化、类过氧化物酶的性质,是一类很有应用前景的多模式肿瘤治疗试剂.

Electrochemical Regulation of Antibacterial Activity Using Ferrocene-Containing Antibiotics

The widespread use of antibiotics causes the accumulation of a large amount of antibiotics in the environment.Excessively active antibiotics in the environment results in the emergence of bacterial resistance.Building smart antibiotics capable of reversible regulation between active and inactive states on demand is a promising approach to address this issue.Herein,a ferrocene-containing quaternary ammonium compound has been developed for electrochemical redox-controlled bacterial inhibition.The reversible switch of the reduced and oxidized ferrocene groups between hydrophobic and hydrophilic states triggers the assembly and disassembly of the micelles while modulating the interactions of antibiotic molecules with the bacteria membrane,providing a new way to regulate antibacterial activity.In addition,the alternate use of reduced and oxidized antibiotics exhibits a favorable effect in preventing bacterial resistance.Thus,an unconventional strategy is offered to prevent the build-up of active bactericide in the environment and decrease bacterial resistance.