We present a systematic investigation of the formation mechanism of carbogenic nanoparticles (CNPs), otherwise referred to as C-dots, by following the pyrolysis of citric acid (CA)-ethanolamine (EA) precursor at different temperatures. Pyrolysis at 180 °C leads to a CNP molecular precursor with a strongly intense photoluminescence (PL) spectrum and high quantum yield formed by dehydration of CA-EA. At higher temperatures (230 °C) a carbogenic core starts forming and the PL is due to the presence of both molecular fluorophores and the carbogenic core. CNPs that exhibit mostly or exclusively PL arising from carbogenic cores are obtained at even higher temperatures (300 and 400 °C, respectively). Since the molecular fluorophores predominate at low pyrolysis temperatures while the carbogenic core starts forming at higher temperatures, the PL behavior of CNPs strongly depends on the conditions used for their synthesis.

The self-assembly of a fragment of the amyloid beta peptide that has been shown to be critical in amyloid fibrillization has been studied in aqueous solution. There are conflicting reports in the literature on the fibrillization of Abeta (16-20), i.e., KLVFF, and our results shed light on this. In dilute solution, self-assembly of NH 2-KLVFF-COOH is strongly influenced by aromatic interactions between phenylalanine units, as revealed by UV spectroscopy and circular dichroism. Fourier transform infrared (FTIR) spectroscopy reveals beta-sheet features in spectra taken for more concentrated solutions and also dried films. X-ray diffraction and cryo-transmission electron microscopy (cryo-TEM) provide further support for beta-sheet amyloid fibril formation. A comparison of cryo-TEM images with those from conventional dried and negatively stained TEM specimens highlights the pronounced effects of sample preparation on the morphology. A comparison of FTIR data for samples in solution and dried samples also highlights the strong effect of drying on the self-assembled structure. In more concentrated phosphate-buffered saline (PBS) solution, gelation of NH 2-KLVFF-COOH is observed. This is believed to be caused by screening of the electrostatic charge on the peptide, which enables beta sheets to aggregate into a fibrillar gel network. The rheology of the hydrogel is probed, and the structure is investigated by light scattering and small-angle X-ray scattering.

We report the synthesis of multifunctional hybrids in both films and bulk form, combining electrical and ionic conductivity with porosity and catalytic activity. The hybrids are synthesized by a two-step process: (a) ice templation of an aqueous suspension comprised of Nafion, graphite oxide, and chloroplatinic acid to form a microcellular porous network and (b) mild reduction in hydrazine or monosodium citrate which leads to graphene-supported Pt nanoparticles on a Nafion scaffold.

Abstract*Corresponding author: MAlbedAlhnan@uclan.ac.uk This work aims to employ fused deposition modelling 3D printing to fabricate immediate release pharmaceutical tablets with various model drugs. It investigates the addition of nonmelting filler to methacrylic matrix to facilitate FDM 3D printing and explore the impact of i) the nature of filler, ii) compatibility with the gears of the 3D printer and, and iii) polymer: filler ratio on the 3D printing process. A specially developed filament based on pharmaceutically approved methacrylic polymer (Eudragit E) and thermally stable filler, TCP (tribasic calcium phosphate) was optimised. Four model drugs (with different physicochemical properties were included into ready-to-use mechanically stable tablets with immediate release properties. Amongst the investigated fillers in this work, directly compressible lactose, spray-dried lactose and microcrystalline cellulose showed a level of degradation at 135 o C whilst talc and TCP allowed consistent flow of the filament and a successful 3D printing of the tablet. Following the two thermal processes (hot melt extrusion (HME) and fused deposition modelling (FDM) 3D printing), drug contents were 94.22%, 88.53%, 96.51% and 93.04% for 5-ASA, captopril, theophylline and prednisolone respectively. XRPD indicated that a fraction of 5-ASA, theophylline and prednisolone remained in the crystalline form whilst captopril was in amorphous form. By combining the advantages of thermally stable pharmaceutically approved polymers and fillers, this unique approach provides a low cost production method for on demand manufacturing of individualised dosage forms.

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Graphite oxideNafion hybrids with a high degree of alignment are cast from aqueous solution in the absence of any external field and reduced in situ by exposure to hydrazine to produce grapheneNafion hybrids (see image). Dramatic enhancement of electrical conductivity indicates sufficient accessibility of the inorganic nanosheets to the reducing agent, through the nanochannels formed by the polymeric ionic domains.

Nine triblock copolymers of ethylene oxide and styrene oxide (type EmSnEm, E ) oxyethylene, S ) oxyphenylethylene, n and m ) number-average block lengths) were prepared by sequential oxyanionic polymerization. Surface tensiometry was used to determine critical micelle concentrations (cmc's) and standard enthalpies of micellization, and isothermal titration calorimetry was used to confirm the enthalpy of micellization. Light scattering was used to determine micellar association numbers and hydrodynamic radii. Phase diagrams defining regions of hard and soft gel were determined by tube inversion and Couette rheometry. Comparison is made with reported results for diblock copolymers of ethylene oxide and styrene oxide and, so far as possible, with results for triblock copolymers of ethylene oxide and styrene. Compilation of values of the cmc for three series of triblock copoly(oxyalkylene)s, EmSnEm, EmBnEm (B ) oxybutylene), and EmPnEm (P ) oxypropylene), reveals a discontinuity in the block length dependence of log(cmc) at S6 and B12.

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