A double‐responsive amphiphilic random copolymer (P(OEtOxA)‐ran‐PNBA) composed of thermoresponsive poly(oligo(2‐ethyl‐2‐oxazoline)acrylate) (P(OEtOxA)) segments and photocleavable poly(2‐nitrobenzyl acrylate) (PNBA) segments is synthesized via combination of cationic ring‐opening polymerization (CROP) and reversible addition‐fragmentation chain transfer (RAFT) polymerization techniques. The P(OEtOxA)‐ran‐PNBA copolymer exhibits lower critical solution (LCST)‐type soluble‐to‐turbid phase transition in water with tunable cloud point (Tcp) with respect to chain length of P(OEtOxA) segment present. The photocleavage of PNBA segments by UV irradiation transforms amphiphilic P(OEtOxA)‐ran‐PNBA to fully hydrophilic P(OEtOxA)‐ran‐poly(acrylic acid) resulting in the appreciable increase of Tcp of copolymer in aqueous solution. Owing to the amphiphilic nature, the P(OEtOxA)‐ran‐PNBA copolymer molecules self‐assemble into well‐dispersed spherical micelles in water. There is a disruption of the copolymer micelles with UV light irradiation as well as shrinkage of micellar size with increasing temperature above the LCST of copolymer in solution. Finally, the encapsulation of hydrophobic guest molecule (nile red) into P(OEtOxA)‐ran‐PNBA copolymer micelles and thermo‐ and photo‐triggered release of nile red are demonstrated. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1714–1729

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Extended stay at HAA may be a risk factor for development of symptomatic portal system thrombosis.

A fluorescent amphiphilic poly(ethylene glycol)-peptide-fluorophore-peptide-poly(ethylene glycol) (PEG-Pep-F-Pep-PEG) triblock conjugate with a hydrophobic fluorophore moiety at the centre of the chain is synthesized by "grafting to" technique based on Schiff-base coupling chemistry. The conjugate is characterized by nuclear magnetic resonance (NMR), circular dichroism (CD), and fluorescence spectroscopy techniques. The aqueous solution of the triblock conjugate emits blue light and exhibits a fluorescence emission band at 430 nm. The amphiphilic conjugate molecules undergo self-assembly into micelles (D ≈ 15-20 nm) in aqueous solution as confirmed from transmission electron microscopy (TEM) and dynamic light scattering (DLS). The critical aggregation concentration is determined by pyrene fluorescence assay and is found to be 0.051 mg mL(-1) . The highly stable and low toxic fluorescent PEG-Pep-F-Pep-PEG conjugate micelles are used for imaging of HeLa cells.

A designed orthogonal dual initiator is employed to construct poly(methyl methacrylate)‐block‐polytyrosine copolymer conjugates via the combination of atom‐transfer radical polymerization of methyl methacrylate, “click” chemistry and ring‐opening polymerization of tyrosine–α‐amino acid N‐carboxyanhydride monomer. The polymer–polypeptide conjugate undergoes self‐aggregation in dimethylformamide to produce hybrid micro/nanospheres owing to the formation of composite micelle as evidenced from field emission scanning electron microscopy and dynamic light scattering study. A simple solution‐based approach is described to encapsulate an organic dye (Rhodamine‐6G) into the aggregated hybrid micro/nanospheres.

A solution-phase reduction method is undertaken to produce polymer magnetic bimetallic CuNi nanoalloy with chain-like structures, which are formed by the magnetic dipole-directed assembly of spherical alloy nanoparticles as confirmed from TEM analysis. Magnetic property measurement reveals paramagnetic nature of the alloy nanochain. These polymer-capped chain-like alloy nanoparticles are dispersible in water as well as in organic solvents that increase their ease of application as catalyst in both of these environments. The XPS and zeta potential analysis demonstrates the presence of Cu(I) on the alloy particle surface and justifies their catalytic activity toward alkyne–azide click reactions. Consequently, the catalytic activity of the as-synthesized polymer CuNi alloy nanochain is investigated toward a wide variety of alkyne–azide click reactions at room temperature in water and in DMF. Depending upon the nature of the substrate and the surface stabilizing polymer on the nanocatalyst, a moderate to quantitative yield of the click-conjugated product is obtained. Additionally, the advantage of pseudohomogeneity of CuNi nanoalloy suspension is utilized to modify polymer end group with amino acid and peptide with ionic liquid via click reaction to create new bioconjugates. Moreover, the nanoalloy catalyst is magnetically recoverable and reusable up to three cycles of click reactions without losing much of its original activity.

A packed bed bioreactor efficiently treated low-level radioactive waste for years with a retention time of 24 h using acetate as the sole carbon source. However, there was generation of dead biomass. This bioreactor biomass was used to develop a bacterial consortium, which could perform the function within 4 h while simultaneously accumulating nitrate and phosphate. The dead mass was negligible. Serial dilution technique was used to isolate the world's first pure culture of a nitrate accumulating strain from this consortium. This isolate could simultaneously accumulate nitrate and phosphate from solution. Its ability to form biofilm helped develop a packed bed bioreactor system for waste water treatment, which could optimally remove 94.46% nitrate within 11 h in batch mode while 8 h in continuous mode from waste water starting from 275 ppm of nitrate. The conventional approach revealed the strain to be a member of genus Bacillus but showed distinct differences with the type strains. Further insilico analysis of the draft genome and the putative protein sequences using the bioinformatics tools revealed the strain to be a novel variant of genus Bacillus. The sequestered nitrate and phosphate within the cell were visualized through electron microscopy and explained the reason behind the ability of the isolate to accumulate 1.12

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