Synthesis of Poly(acyclic orthoester)s: Acid-Sensitive Biomaterials for Enhancing Immune Responses of Protein Vaccine

While poly(acyclic orthoester)s (PAOEs) have many appealing features for drug delivery, their application is significantly hindered by a lack of facile synthetic methods. Reported here is a simple method for synthesizing acyclic diketene acetal monomers from diols and vinyl ether, and their polymerization with a diol to first synthesize PAOEs. The PAOEs rapidly hydrolyze at lysosomal pH. With the help of a cationic lipid, ovalbumin, a model vaccine antigen was efficiently loaded into PAOEs nanoparticles using a double emulsion method. These nanoparticles efficiently delivered ovalbumin into the cytosol of dendritic cells and demonstrated enhanced antigen presentation over poly(lactic-co-glycolic acid) (PLGA) nanoparticles. PAOEs are promising vehicles for intracellular delivery of biopharmaceuticals and could increase the utility of poly(orthoesters) in biomedical research.     

Electro- and magnetostatics of reinforced polymers

On the basis of previously proposed models of reinforced media with regular structure, a method is developed for determining the electromagnetic fieldand dielectric and magnetic constants of reinforced polymers treated as ideal dielectrics. The solution obtained describes the static electromagnetic field and is suitable for investigating the propagation in reinforced media of electromagnetic waves whose length exceeds the distance between adjacent fibers. The dependence of the macroscopic constants on the orientation and volume content of the reinforcement is investigated.Institute of Mechanics, AS UkrSSR, Kiev. Translated from Mekhanika Polimerov, Vol. 4, No. 6, pp. 1130–1133, November–December, 1968.     

PCR protocol- and inulin catabolism-based differentiation of inulinolytic soil bacteria

Applied Biochemistry and Biotechnology - Bacteria collected from rotting dahlia tubers, instead of degrading inulin to D-fructose, preferentially formed the known DFA III (Β-2.1′:...     

Phase-transfer catalysis in the nickel- and palladium-catalyzed formation of aryl and alkenyl sulfides

Aryl and alkenyl sulfides can be conveniently prepared from the corresponding halides and alkaline thiolates under phase transfer conditions in the presence of σ-Aryl-Ni[P(C₆H₅)₃]₂Cl or σ-Aryl-Pd[P(C₆H₅)₃]₂Br.     

Reticular Synthesis of One-Dimensional Covalent Organic Frameworks with 4-c sql Topology for Enhanced Fluorescence Emission

Covalent organic frameworks (COFs) have been extensively investigated due to their unique structure, porosity, and functionality. However, at the topological level, COFs remain as two-dimensional (2D) or three-dimensional (3D) structures, while COFs with one-dimensional (1D) topology have not been systematically explored. In this work, we proposed a synthetic strategy for the construction of 1D-COFs based on non-linear edges and suitable high-symmetry vertices. Compared with their 2D-COFs counterparts, the 1D-COFs with AIEgens located at the vertex of the frame exhibited enhanced fluorescence. The density functional theory (DFT) calculations revealed that the dimensional-induced rotation restriction (DIRR) effect could spontaneously introduce additional non-covalent interactions between the strip frames, which could substantially diminish non-radiative transitions. This work also provides protocols for the design of 1D-COFs and a guidance scheme for the synthesis of emitting COFs.     

Author Correction: Identification of a Novel Feruloyl Esterase by Functional Screening of a Soil Metagenomic Library

Applied Biochemistry and Biotechnology - The original version of this article unfortunately contained a mistake in the image and caption of Fig. 6. The corrected version of the image and caption is...     

CTAB透性化酵母细胞生物催化合成(S)-(+)-3-羟基丁酸乙酯

 利用十六烷基三甲基溴化铵(CTAB)透性化啤酒酵母细胞中高活性的脱氢酶,借助于辅助底物乙醇和葡萄糖,对3-羰基丁酸乙酯(EOB)不对称还原合成(S)-(+)-3-羟基丁酸乙酯((S)-(+)-3-EHB)进行了研究. 结果表明,CTAB透性化酵母细胞中的醇脱氢酶和6-磷酸葡萄糖脱氢酶的活性分别比未经处理的酵母细胞高482倍和6.5倍. 在相同条件下,CTAB透性化细胞对EOB的还原比未经处理的酵母细胞快. 细胞浓度对反应有明显影响,当透性化酵母细胞浓度＜90 mg/ml时,(S)-(+)-3-EHB的产率和对映体过量值都较低; 当酵母细胞浓度≥90 mg/ml,在最佳进料速率、最适温度和pH条件下,振摇速度为125 r/min时, (S)-(+)-3-EHB的浓度达到最大值314 mmol/L. 在反应开始的6 h内,(S)-(+)-3-EHB的产率可达94%,对映体过量值≥98%,但24 h后产率和对映体过量值分别降低到85%和91%.