CO2 bubble-assisted nonsolvent-induced phase inversion separation (NIPS) technique has demonstrated remarkable advantages in fabricating ultrafiltration (UF) membranes with high porosity and narrow pore size distribution. In this study, an improved CO2 bubble-assisted NIPS was developed by incorporating polyethyleneimine (PEI) into the casting solution to form a homogeneous single-phase system, thereby avoiding the aggregation issues commonly associated with using CaCO3 as the CO2 foaming source. The freshly cast nascent membrane was exposed to a CO2 atmosphere, allowing rapid CO2 adsorption by the surface PEI layer, followed by immersion in an acidic coagulation bath to trigger prompt CO2 desorption. By tuning the CO2 adsorption and desorption conditions, the phase separation dynamics and membrane pore morphology were effectively regulated. The resulting membrane exhibited a surface porosity of 14.7%, a narrow pore size distribution, and an average pore diameter of approximately 10.5 nm. The influence of factors such as the casting solution solvent type and temperature, CO2 adsorption time, and coagulation bath pH on the membrane structure was investigated. The membrane formation mechanism was analyzed based on SEM surface morphology with XPS. The fabricated membrane exhibited excellent performance, with a pure water permeance of 653.1 L·m−2·h−1·bar−1 and a high rejection rate of 98.5% toward bovine serum albumin. This work provides an effective strategy for fabricating UF membranes with high porosity and narrow pore size distribution.

Chemotherapy remains the primary treatment for cancer; however, conventional chemotherapeutic drugs have several shortcomings, including poor solubility, lack of targeting, low bioavailability, and high toxicity to healthy tissues. In order to overcome these limitations, drug delivery systems (DDS) have emerged as a promising alternative. In this study, we synthesized TPGS3350-PVGLIG-SS-DOX polymeric micelles that incorporate both extracellular MMP2/9 enzyme response and intracellular reduction response at a nanoscale level. The micelles remained stable throughout the blood circulation and only aggregated at the tumor sites, thanks to the enhanced permeability and retention (EPR) effect. Moreover, the tumor tissue showed a high expression of MMP2/9 enzymes, which resulted in the cleavage of the PVGLIG peptide sequence, ultimately leading to an improved phagocytosis efficiency. Under the action of high intracellular GSH concentration, the disulfide bond was broken and DOX was released to induce tumor cell death. The TPSD&D micelles exhibited good tumor inhibitory activity in vivo and significantly reduced toxic side effects on normal tissues. Our work provides a simple method to assemble tumor-targeted prodrug micelles to improve cancer therapy, which holds potential for clinical applications in antitumor therapy.

This study aims to prepare and investigate thin film composite (TFC) membranes with a highly positively charged rejection layer for effective separation of Mg2+/Li+. The aqueous phase monomer employed in fabricating the TFC membranes was a highly ionic and hydrophilic guanidinium, namely 1,3-diaminoguanidine hydrochloride (DAGH), using an interfacial polymerization method. Two methods were used to prepare the TFC membranes: conventional interfacial polymerization and support-free interfacial polymerization. The surface properties and morphologies of the TFC membranes were characterized by FESEM, AFM, surface zeta-potential, and water contact angle. The XPS was used to analyze the crosslinking structure of the interfacial layer. The study results revealed that the SF-TFC membrane had a higher crosslinking density and zeta-potential compared to the C-TFC membrane. Notably, SF-TFC exhibited a MgCl2 rejection of 95.09% at 7 bar, and for Mg2+/Li+ separation, the SF-TFC membrane had a Li+/Mg2+ separation factor of 23.32 at the Mg2+/Li+ mass ratio of 10. Additionally, the strong ionic and hydrophilic properties of DAGH led to the proposal of an aqueous-phase polymerization mechanism, substantiated by AFM and ESI-MS analysis.

聚酰胺复合膜以其优良的稳定性及良好的分离选择性成为水处理和化工分离领域应用范围最广的分离材料之一.聚酰胺复合膜一般采用界面聚合法制备,由于界面聚合反应活性高、反应参数多,致使界面层结构难以控制,膜的渗透性或选择性不理想.因此,如何有效调控膜结构,实现膜的高渗透性或选择性是目前面临的重要挑战.近期诸多研究表明,在水相或有机相中引入添加剂可以改变油水界面张力进而调控单体界面扩散速率及界面分布,或通过改变反应机理影响聚合反应速率,最终实现对界面层结构和膜性能的调控.本文从添加剂种类、性质和调控作用等角度总结了近年来添加剂对复合膜结构及性能调控的研究进展,分析了现有研究存在的问题,并建议从微观层面探究界面过程的物理化学性质以及开发高时间分辨率原位表征方法等.

Au@Ag/TiO2/Ti3C2 exhibits outstanding photoreduction activity at 0 °C because of the combination of efficient hot carrier generation and separation ability in one system.

This study focused on atrazine concentration by integrating forward osmosis (FO) technology into the microfluidic chip. It mainly investigated the strengthening effect of the capillary force difference caused by different microchannel sizes on the FO process. A 5:1 ratio of 30 % NaCl and 0.001 % [C3H3O2Na]n solution was selected as draw solution because of its high draw flux and low flux decay rate. Qualitative experiments indicated that atrazine concentration rate of FO chip is significantly higher than that of the conventional FO device. The size difference between the upper and lower microchannels is positively related to the auxiliary effect of capillary force. A multi-channel parallel mode was developed in the draw solution side of FO chip to increase the mass transfer efficiency. Results indicated that the increase in the number of microchannels greatly improve the concentration efficiency. Subsequently, a series of low-concentration atrazine solutions were concentrated to determine the detection limit of atrazine. The initially diluted atrazine solution (2.784 x 10- 7 mol/L) below detection limit of ultraviolet spectrophotometer was concentrated about 8 times, reaching the detection limit (2.237 x 10-6 mol/L) in 32 min.

Polyelectrolyte-based draw solution(PBDS) exhibit high osmotic pressure, and low reverse solute leakage, which are highly demanded in forward osmosis process. Additionally, various separation methods such as nanofiltration, ultrafiltration and thermal treatment can be utilized for its recycle, rendering PBDS an ideal substitute for the traditional inorganic draw solution such as sodium chloride. In the past two decades, research works concerning PBDS have been intensively reported. Because PBDS has distinctive properties in comparison with inorganic draw solution, thus, it is necessary to review these developments in PBDS and present an outline. This paper aims to review the recent developments in PBDS in consideration of their chemical structures, which are categorized into carboxylate type, sulfonate type, amine type and amide type. In the beginning, the general considerations for an ideal PBDS are introduced. Subsequently, the molecular weight of the polyelectrolytes, the osmotic pressure and viscosity of the draw solutions, the water flux and reverse solute leakage in forward osmosis process are introduced in detail. The corresponding mechanisms of forward osmosis are also described. Finally, the characteristics, advantages and drawbacks of the PBDS are summarized, and the opportunities and challenges are discussed.

A convenient, highly sensitive and reliable assay for 2,4,6‑trinitrophenol (TNP) and Fe (III) ion (Fe3+) in the dual spectroscopic manner is developed based on novel carbon dots (CDs). The CDs with highly blue emitting fluorescent were easily prepared via the one-step potassium hydroxide-assisted reflux method from dextrin. The as-synthesized CDs exhibited the high crystalline quality, the excellent fluorescence characteristics with a high quantum yield of ~13.1%, and the narrow size distribution with an average diameter of 6.3±0.5nm. Fluorescence and frequency doubling scattering (FDS) spectra of CDs show the unique changes in the presence of TNP/Fe3+ by different mechanism. The fluorescence of CDs decreased apparently in the presence of TNP via electron-transfer. Thus, after the experimental conditions were optimized, the linear range for detection TNP is 0-50μM, the detection limit was 19.1nM. With the addition of Fe3+, the FDS of CDs appeared to be highly sensitive with a quick response to Fe3+ as a result of the change concentration of the scattering particle. The emission peak for FDS at 450nm was enhanced under the excitation wavelength at 900nm. The fluorescence response changes linearly with Fe3+ concentration in the range of 8-40μM, the detection limits were determined to be 44.1nM. The applications of CDs were extended for the detection of TNP, Fe3+ in real water samples with a high recovery. The results reported here may become the potential tools for the fast response of TNP and Fe3+ in the analysis of environmental pollutants.

随着,高校对实验安全的重视程度逐渐加深,开设实验室安全相关的课程成为必要,有助于学生提升实验安全意识并且使其掌握一定安全事故初期处置技能.危化品安全管理作为实验安全教育课程中的重要组成部分,发挥着积极的作用.通过改进其课程内容的设置,来达到丰富教学内容和授课方式,使学生的参与度提升,增强学生的学习兴趣.

Study on interaction mechanism between synthetic receptor and phosphorylated peptides is of great importance for phophopeptide enrichment and early disease-detection. In this study, association between Zn2+-coordination type synthetic receptor and some model phosphorylated peptides was studied, the receptor contains Zn2+-dipicolylamine and guanidiniocarbonyl pyrrole tethered by hydrophobic spacer. Isothermal titration calorimetry was used to elucidate the association thermodynamics. The receptor displayed higher affinity to bis-phosphorylated peptides in comparison with mono-phosphorylated peptides, and the association constant was 10-40 times higher for bis-phosphorylated peptides than that of mono-phosphorylated peptides. Space between the two phosphate groups showed great influence on the association, i. e. association constant remarkably decreased as the space increased. For mono-phosphorylated peptides, the position of phosphate in the sequence affected the affinity. The results are expected to provide insights into the principle for the design of receptor for peptides.

Iron-coated TiO2 coaxial nanotubes (Fe2O3/TiO2 nanotubes) synthesized by treating TiO2 nanotubes with Fe(OH)(3) sol are used as a support, and gold nanoparticles are loaded on the support by a simple one-pot strategy using lysine as both the linker and the capping agent. The obtained Au/Fe2O3/TiO2 hybrid nanotube materials are characterized by TEM, XRD, XPS, UV-vis, AAS and nitrogen adsorption. The photocatalytic performance is evaluated by the photocatalytic degradation rates of methyl orange under UV light irradiation. The effects of Au content, the absence/presence of lysine and Fe2O3, the pH value of solution and the addition amount of H2O2 to solution on the photocatalytic performance of Au/Fe2O3/TiO2 nanotubes are investigated. The results reveal that gold nanoparticles capped by lysine can be highly dispersed on the supports against aggregation, and the products exhibit higher thermal stability and photocatalytic activity in comparison to pristine TiO2 nanotubes.

Association between zinc(ii)-dipicolylamine appended beta-cyclodextrin and CTD (carboxy-terminal domain of RNA polymerase II) peptides with different phosphorylation patterns was studied by ITC and NMR.

In this study, association between zinc (II) and dipicolylamine was studied by isothermal titration calorimetry. At neutral of weakly alkaline conditions, with zinc (II) in cell and dipicolylamine in syringe, increasing heat release was observed as the titration proceeded. Considering the equilibrium between Zn2+ and Zn(OH)(2) at these conditions, the increasing heat release is ascribed to the increasing solubilization of colloidal Zn(OH)(2) followed by neutralization of OH- by the buffer. Though quantitative determination of the increase in solubility is not accomplished, to the best of our knowledge, this is the first report about solubility increase of colloidal zinc hydroxide using calorimetric method. (C) 2014 Elsevier Ltd. All rights reserved.

This paper reports an active decapeptide inhibitor (RR: RYYAAFFARR) of β-amyloid (Aβ(1-40)) aggregation. Traditional inhibitors target the hydrophobic core of Aβ (Aβ(16-20)) and were designed based on the single hydrophobic interaction. RR was designed to target an extended region (Aβ(11-23)), which contains three important regions of Aβ(1-40). RR exhibits stronger binding affinity for Aβ(1-40) (K(D) = 1.10 μM) than the known β-sheet breaker LPFFD (K(D) = 156 μM). Our study shows that RR inhibited the fibrillation of Aβ(1-40) by nearly 75% at an equimolar concentration, and that a 1:4 ratio of Aβ(1-40)/ RR almost completely inhibited fibrillation. The interaction mechanism was also investigated by changing the ionic strength or the structure of RR. The results revealed that RR binds to Aβ(1-40) because of its strong affinity for Aβ(11-23), which is mainly driven by hydrophobic and electrostatic interactions and hydrogen bonding.

创新实验室是以培养大学生创新精神和创新能力为目标的创新实验室。本文论述了大学开设本科生化学创新实验室的必要性，结合我校近年的教学实践阐述了本科生化学创新实验室的建设内容，最后探讨本科生化学创新实验室管理模式，指出教师与学生共同管理模式，实验室与学生社团共建共管应该成为本科生化学创新实验室管理的方向。

“界面现象”是大学物理化学课程中的一个重要章节，而开尔文公式是其中的一个重要的知识点。尽管其热力学推导过程较为繁琐及抽象，但一些情况下仅需对其结果进行定性的理解。本文描述了以碰撞模型对开尔文公式的定性解释。

物理化学实验课程网络系统的建立，可便于学生一目了然地自主选修所需课程，在无时间、地域限制情况下，学生可以随时随地了解实验内容、关注实验前沿动态、实时选修实验课程、学习实验原理、实验过程，并熟悉仪器的操作方法及相关注意事项等内容，从而可以与理论教学有机结合。巩固、消化课堂教学知识，透彻理解物理化学，拓展知识面，培养学习物理化学的兴趣，培养科研兴趣；全面提高教学质量；进一步建设市级物理化学精品课课程。

Gold nanoparticles (AuNPs) have significant potential as biosensors and drug delivery vehicles, as well as imaging and thermotherapy agents. Thiol-containing polyethylene glycol (PEG), hereafter denoted as thiol-PEG, is widely used as a macromolecular ligand for modifying AuNPs and stabilizing them under various environments. In this work, a series of thiol-PEG-modified AuNPs (PEGylated AuNPs) with different PEG molecular weights (Mw) were synthesized. The saturated capping density, charge-screening ability, and stability of the PEGylated AuNPs were then examined. The results showed that high-Mw PEG stabilized the AuNPs and screened the surface charge better than low-Mw PEG, but the latter showed higher saturated capping density. More importantly, PEG exhibited the maximum coagulation concentration (MCC) and critical stabilization concentration (CSC) in the stabilizing process of the AuNPs. Thiol-PEG acted as an AuNP stabilizer only when its concentration was higher than the CSC. Otherwise, thiol-PEG accelerated AuNPs aggregation, which reached the peak level at the MCC. These results were significant in recognizing the influence of thiol-PEG on the stability of AuNPs.

In this study, a receptor for phosphorylated peptide was developed. The receptor contains Zn2+–dipicolylamine (Zn–Dpa) moiety at one end and guanidiniocarbonyl pyrrole at the other. The association between the receptor and CTD (carboxy-terminal domain of RNA polymerase II) peptides with different phosphorylated patterns was investigated by isothermal titration calorimetry and molecular docking, and the receptor showed much higher affinity towards bis-phosphorylated CTD peptide with affinity constant K=1.09×105.

A rapid, effective method for the screening of adsorbent ligands based on the unique optical properties of gold colloid has been developed. Different interactions between adsorbate and ligands induce different states of aggregation of the gold colloid, and the associated distinct color changes of the colloid have been utilized to estimate the affinity of the ligands toward the adsorbate. In this work, phosphorylated peptide CGGFGGpSG was appended to a gold colloid to obtain the adsorbate-modified gold colloid (CG8-AuNPs). Candidate ligands Dpa-Zn(2+), DMAPAA, and AAn were copolymerized with acrylamide to form linear polymers and cross-linked CG8-AuNPs to induce aggregation. Screening of the candidate ligands revealed that Dpa-Zn(2+) showed the highest affinity among those tested, inducing a color change of the gold colloid at a concentration of 10 μM, which is much lower than those of ligands DMAPAA (40 μM) and AAn (almost no color change could be observed). Subsequent statistical adsorption experiments confirmed these screening results, with the adsorbent A-AAm-Dpa-Zn(2+) showing the highest adsorption capacity (426 mg/g) for CG-8, almost twice that of adsorbent A-AAm-DMAPAA. This reported method has low sample consumption, and the screening may be simply monitored by the naked eye.