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As their manufacturing and consumption have increased, pharmaceutical chemicals have increasingly been found in wastewater.

In this paper, we successfully synthesized heterojunction manganese titanate/titanate nanoparticles (MnTiO3–TiO2 NPs)-decorated carbon nanofibers (CNFs) employing the electrospinning process. The morphology, crystallinity, and chemical composition of the MnTiO3/TiO2-decorated CNFs is characterized via SEM, FESEM, STEM, TEM EDX, and XRD techniques. The synthesized nanocomposite exhibits good performance for photodegradation of methylene blue (MB) dye and hydrolysis of ammonia–borane complex for hydrogen releasing experiment in a batch reactor under visible light. A mathematical model was developed to predict the photocatalytic activity of the produced nanocomposite with various parameters. The operational parameters include the effect of the initial concentration, catalyst dosage, light intensity, and reaction temperature, which are studied to validate the mathematical model. The reaction rate constant of MB photodegradation is found to be 0.0153 min−1 for an initial MB concentration of 5 mg·L−1 with a catalytic dosage of 200 mg·L−1 at a reaction temperature of 25°C under a light intensity of 25 W·m−2. Similarly, the H2 generation employing TiO2@CNFs and MnTiO3/TiO2@CNFs under visible light irradiation is observed to be 0.31 mol and 2.95 mol, respectively, corresponding to an exposure of 10 min. We also demonstrated that the yield of hydrogen employing MnTiO3/TiO2@CNFs under visible light increases to 2.95 mol compared with 1.51 mol in darkness. Finally, comparisons were made between the experimental and model-predicted values of the reaction rate constant and final concentrations. Theoretical and experimental data of photocatalytic activity are found to be in good agreement for MnTiO3/TiO2@CNFs.

In this work we demonstrate one-pot glycidol synthesis, via trans-esterification between glycerol and dimethyl carbonate, by making use of commercially available sodium methoxide as a catalyst. An excellent glycerol conversion (99%) and remarkable glycidol yield (75%) was obtained using dimethyl carbonate/glycerol (molar ratio 2:1) in the presence of 3 wt% catalyst amount (with respect to glycerol weight) at 85 °C for a reaction time of 120 min. Sodium methoxide was recycled and reused twice with only a slight decrease in glycerol conversion. The water content of the glycerol reached 2.5 wt%; this did not reduce the glycerol conversion efficiency of the catalyst. A plausible mechanism for the trans-esterification involved in the preparation of glycidol was proposed.

In this work, porous silicon (P-Si) structures were fabricated by anodizing n-type monocrystalline Si into an ethanoic-HF solution. Anisotropic electrochemical etching with constant time and current density was carried out to fabricate pores and their average diameter was found to be . Raman spectra exhibited widened peaks for red, blue, and green wavelengths. The widened photoluminescence (PL) spectrum was blue-shifted owing to the quantum confinement effect. The P-Si exhibited an energy gap of 1.80 eV and manifested a direct bandgap. The photoresponse of the fabricated P-Si based device was studied at different laser irradiation wavelengthsin the range of 400–1100 nm. The best photoresponse was observed for 785 nm wavelength and the corresponding sensitivity was determined to be 9.4%. Hence, the P-Si can potentially be used for visible range photodetectors.

The sequence and helical content of two alanine-rich peptides (AQK18 and GpAQK18, Gp: l-propargylglycine) and their conjugates with poly(ethylene glycol) (PEG) have been investigated by multidimensional mass spectrometry (MS), encompassing electrospray ionization (ESI) or matrix-assisted laser desorption ionization (MALDI) interfaced with tandem mass spectrometry (MS2) fragmentation and shape-sensitive separation via ion mobility mass spectrometry (IM-MS). The composition, sequence, and molecular weight distribution of the peptides and bioconjugates were identified by MS and MS2 experiments, which also confirmed the attachment of PEG at the C-terminus of the peptides. ESI coupled with IM-MS revealed the existence of random coil and α-helical conformers for the peptides in the gas phase. More importantly, the proportion of the helical conformation increased substantially after PEG attachment, suggesting that conjugation adds stability to this conformer. The conformational assemblies detected in the gas pha...

The biodegradable polyester copolymer poly(propylene fumarate) (PPF) is increasingly utilized in bone tissue engineering studies due to its suitability as inert cross-linkable scaffold material. The well-defined poly(propylene fumarate) oligomers needed for this purpose are synthesized by post-polymerization isomerization of poly(propylene maleate), which is prepared by ring opening polymerization of maleic anhydride and propylene oxide. In this study, multidimensional mass spectrometry methodologies, interfacing matrix-assisted laser desorption ionization and electrospray ionization with mass analysis, tandem mass spectrometry fragmentation and/or ion mobility mass spectrometry, have been employed to characterize the composition, end groups, chain connectivity and isomeric purity of the isomeric copolyesters poly(propylene maleate)and poly(propylene fumarate). It is demonstrated that the polymerization catalyst is incorporated into the polymer chain (as the initiating chain end) and that the poly(propylene maleate) to poly(propylene fumarate) isomerization using an amine base proceeds with quantitative yield. Hydrolytic degradation is shown not to alter the double bond geometry of the poly(propylene fumarate) or poly(propylene maleate) chains.

A novel, tetrakisterpyridinyl-substituted porphyrin underwent self-assembly to form a three-dimensional, belt-shaped metallomacrocycle, which was characterized by 1D and 2D NMR and electrospray ionization traveling wave ion mobility mass spectrometry.

Biocompatible polymers such as poly(ethylene glycol) (PEG) have been successfully conjugated to therapeutic proteins to enhance their pharmacokinetics. However, many of these polymers, including PEG, only improve the in vivo lifetimes and do not protect proteins against inactivation during storage and transportation. Herein, we report a polymer with trehalose side chains (PolyProtek) that is capable of improving both the external stability and the in vivo plasma half-life of a therapeutic protein. Insulin was employed as a model biologic, and high performance liquid chromatography and dynamic light scattering confirmed that addition of trehalose glycopolymer as an excipient or covalent conjugation prevented thermal or agitation-induced aggregation of insulin. The insulin-trehalose glycopolymer conjugate also showed significantly prolonged plasma circulation time in mice, similar to the analogous insulin-PEG conjugate. The insulin-trehalose glycopolymer conjugate was active as tested by insulin tolerance tests in mice and retained bioactivity even after exposure to high temperatures. The trehalose glycopolymer was shown to be non-toxic to mice up to at least 1.6 mg/kg dosage. These results together suggest that the trehalose glycopolymer should be further explored as an alternative to PEG for long circulating protein therapeutics.