Reference of 108-55-4, Enzymes are biological catalysts that produce large increases in reaction rates and tend to be specific for certain reactants and products. 108-55-4, Name is Dihydro-2H-pyran-2,6(3H)-dione, SMILES is O=C1CCCC(O1)=O, belongs to Tetrahydropyrans compound. In a article, author is Li Rongye, introduce new discover of the category.
pH/Solvent Tunable Hierarchical Nanostructures Assembled from an Amphiphilic Polypeptide-containing Triblock Copolymer
Similar to natural proteins, polypeptides can form secondary structures depending on their physical properties. Many efforts have been made towards the self-assembly of triblock copolymer containing polypeptide as an important component to construct hierarchical structures by utilizing the pH-responsive conformation transformation. In this work, a pH-responsive poly(ethylene glycol)-b-poly(L-lysine)-b-poly(styrene) (PEG-b-PLL-b-PS) triblock copolymer was prepared via a combination of controlled ring opening polymerization (ROP) and atom transfer radical polymerization (ATRP). In the triblock copolymer, PLL is water-soluble in acidic solution with random coil conformation, but becomes insoluble helix in alkaline solution. PEG has excellent water solubility that can exhibit protein-resistant property. PS serves as hydrophobic part. Self-assembly of the polymer was examined by transmission electron microscopy (TEM), atomic force microscopy (AFM) and attenuated total reflection-infrared spectrometer (ATR-IR). The triblock copolymer forms spherical micelles in 1 : 1 volume ratio of tetrahydrofuran-water mixed solvent, in which the hydrophobic PS segment forms a core and the two hydrophilic segments PLL and PEG serve as shell and corona, respectively. The spheres as the subunits further transform into hierarchical 1D fiber-like structure in the presence of THE’ after 7 d of aging, confirmed by both TEM and AFM techniques. Upon removing THF, the spherical shape was re-obtained with slightly smaller diameter, so called frozen micelles. Further, the diameter of the spheres increases with pH increasing. A sphere-to-vesicle transition was observed at pH 13 as the secondary conformation of PLL transforms from coil to a-helix. The dialysis of these solutions can convert the vesicles back into spherical morphology with slightly smaller diameter.
Reference of 108-55-4, Each elementary reaction can be described in terms of its molecularity, the number of molecules that collide in that step. The slowest step in a reaction mechanism is the rate-determining step.you can also check out more blogs about 108-55-4.
Reference:
Tetrahydropyran – Wikipedia,
,Tetrahydropyran – an overview | ScienceDirect Topics