Effects of antibiotics and heavy metals on denitrification in shallow eutrophic lakes.

Antibiotic and heavy metal residues in shallow lakes caused by aquaculture and human activities such as sewage discharge have attracted much attention and public concern. However, mechanisms by which these environmental pollutants affect the microorganism-mediated biogeochemical cycle are unknown. This study focused on the effects of antibiotics, heavy metal, and antibiotic resistance genes (ARGs) on denitrification in shallow lakes.

Fluorescent polymer cubosomes and hexosomes with aggregation-induced emission.

Fluorescent polymer cubosomes and hexosomes with aggregation-induced emission (AIE) were prepared from amphiphilic block copolymers PEG--PTPEMA where the hydrophobic block PTPEMA was a polymethacrylate with tetraphenylethene (TPE) as the AIE side group. Four highly asymmetric block copolymers with hydrophilic block weight ratio ≤ 20% were synthesized. Cubosomes and hexosomes with strong fluorescence emission were obtained by nanoprecipitation of polymers with < 9% in dioxane/water and THF/water systems.

Light-Gated Nano-Porous Capsules from Stereoisomer-Directed Self-Assemblies.

Structuring pores into stable membrane and controlling their opening is extremely useful for applications that require nanopores as channels for material exchange and transportation. In this work, nanoporous vesicles with aggregation-induced emission (AIE) properties were developed from the amphiphilic polymer PEG550-TPE-Chol, in which the hydrophobic part is composed of a tetraphenylethene (TPE) group and a cholesterol moiety and the hydrophilic block is a poly(ethylene glycol) (PEG, = 550 Da). Two stereoisomers, -PEG550-TPE-Chol and -PEG550-TPE-Chol, were successfully synthesized.

CO -Activated Reversible Transition between Polymersomes and Micelles with AIE Fluorescence.

Fluorescent polymersomes with both aggregation-induced emission (AIE) and CO -responsive properties were developed from amphiphilic block copolymer PEG-b-P(DEAEMA-co-TPEMA) in which the hydrophobic block was a copolymer made of tetraphenylethene functionalized methacrylate (TPEMA) and 2-(diethylamino)ethyl methacrylate (DEAEMA) with unspecified sequence arrangement. Four block copolymers with different DEAEMA/TPEMA and hydrophilic/hydrophobic ratios were synthesized, and bright AIE polymersomes were prepared by nanoprecipitation in THF/water and dioxane/water systems. Polymersomes of PEG -b-P(DEAEMA -co-TPEMA ) were chosen to study the CO -responsive property.

Nematicidal amide alkaloids from the seeds of Clausena lansium.

Five new amide alkaloids (1-3, 5-6) were isolated from the seeds of Clausena lansium together with one new natural product (4) and four known analogues (7-10). The structures of the new amide alkaloids were elucidated based on a comprehensive spectroscopic data analysis including 1D and 2D NMR as well as HRESIMS, and by comparison with the literature. The bioactivity results showed that compound 8 expressed potent nematicidal activity against Panagrellus redivevus, with IC value of 0.

Fluorescent Polymersomes with Aggregation-Induced Emission.

Fluorescent polymersomes are interesting systems for cell/tissue imaging and in vivo study of drug distribution and delivery. We report on bright fluorescent polymersomes with aggregation-induced emission self-assembled by a series of tetraphenylethylene (TPE)-containing amphiphilic biodegradable block copolymers, where the hydrophilic block is a polyethylene glycol and hydrophobic block is a TPE-substituted trimethylenecarbonate polymer P(TPE-TMC). Their self-assemblies in water were prepared by nanoprecipitation using dioxane or tetrahydrofuran as co-solvent, and the self-assembling processes were studied in detail by cryo-electron microscopy, dynamic light scattering, and spectrofluorometer.

Dual-responsive shape memory hydrogels with novel thermoplasticity based on a hydrophobically modified polyampholyte.

Shape memory hydrogels offer the ability to recover their permanent shape from temporarily trapped shapes without application of external forces. Here, we report a novel dual-responsive shape memory hydrogel with characteristic thermoplasticity. The water-insoluble hydrogel is prepared by simple ternary copolymerization of acrylamide (AM) and acrylic acid (AA) with low amounts of a cationic surfmer, in the absence of organic crosslinkers.

Preparation of anion-exchangeable polymer vesicles through the self-assembly of hyperbranched polymeric ionic liquids.

This work reports the self-assembly of anion-exchangeable vesicles from an amphiphilic hyperbranched polymeric ionic liquid (HBPIL). By a simple one-step anion exchange with methyl orange, the obtained HBPILs could self-assemble into pH-indicative and colorful vesicles in water with color changes directly visible to the naked eye in response to solution pH. In addition, by another step of anion exchange with bovine serum albumin (BSA), the BSA-coated vesicles could also be readily prepared.