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91.
Simon L. Porter Sophie M. Coulter Sreekanth Pentlavalli Garry Laverty 《Macromolecular bioscience》2020,20(7)
Peptide nanotubes are promising materials for a variety of biomedical applications with ultrashort (≤7 amino acids) forms providing particular promise for clinical translation. The manufacture of peptide nanotubes has, however, been associated with toxic organic solvents restricting clinical use. The purpose of this work is to formulate dipeptide nanotubes using mild techniques easily translated to industrial upscale and to characterize their physiochemical and biological properties. Phenylalanine‐phenylalanine variants can be successfully formulated using distilled water as demonstrated here. Formulations are homogenous in shape (tubular), with apparent size (50–260 nm) and a zeta potential of up to +30 mV. L‐(H2N‐FF‐COOH), and D‐enantiomers (H2N‐ff‐COOH) demonstrate no toxicity against glioblastoma cells and are explored for ability to deliver a model hydrophilic molecule, sodium fluorescein, at pH 5.5 (tumor) and 7.4 (physiological). Peptide nanotubes loaded with >85% sodium fluorescein, demonstrate burst release characteristics, fitting the Weibull model of drug release. This research provides important data contributing to the pharmaceutical formulation of peptide nanotubes as drug delivery platforms for hydrophilic drugs. 相似文献
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Inside Cover: Stoichiometrically Controlled Revocable Self‐Assembled “Spiro” versus Quadruple‐Stranded “Double‐Decker” Type Coordination Cages (Chem. Eur. J. 41/2014) 下载免费PDF全文
94.
Stoichiometrically Controlled Revocable Self‐Assembled “Spiro” versus Quadruple‐Stranded “Double‐Decker” Type Coordination Cages 下载免费PDF全文
Sreenivasulu Bandi Dr. Amlan K. Pal Prof. Dr. Garry S. Hanan Prof. Dr. Dillip Kumar Chand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(41):13122-13126
The simple combination of PdII with the tris‐monodentate ligand bis(pyridin‐3‐ylmethyl) pyridine‐3,5‐dicarboxylate, L , at ratios of 1:2 and 3:4 demonstrated the stoichiometrically controlled exclusive formation of the “spiro‐type” Pd1L2 macrocycle, 1 , and the quadruple‐stranded Pd3L4 cage, 2 , respectively. The architecture of 2 is elaborated with two compartments that can accommodate two units of fluoride, chloride, or bromide ions, one in each of the enclosures. However, the entry of iodide is altogether restricted. Complexes 1 and 2 are interconvertible under suitable conditions. 相似文献
95.
Two species of Hawaiian crustaceans, Portunis sanguinolentus and Podophthalmis vigil, are shown to be effective for the construction of antennular receptrodes. The resulting chemoreceptor-based biosensors respond to stimulant compounds at levels below 10?15 M with very short response times. Experimental studies focused on trimethylamine oxide as a novel test compound, combined with chemometric techniques for data analysis, yield quantitative dose-response data over a wide concentration range. 相似文献
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Jonathan Rochez Garry Rodrigue 《Numerical Methods for Partial Differential Equations》2002,18(2):179-192
A multigrid strategy using upwind finite differencing is developed for accelerating the steady state computations of waves, [14] propagating with curvature‐dependent speeds. This will allow the rapid computation of a “burn table.” In a high explosive material, a burn table will allow the elimination of solving chemical reaction ODEs by feeding in source terms to the reactive flow equations for solution of the system of ignition of the high explosive material. Standard iterative methods show a quick reduction of the residual followed by a slow final convergence to the solution at high iterations. Such systems, including a nonlinear system such as this, are excellent choices for the use of multigrid methods to speed up convergence. Numerical steady‐state solutions to the eikonal equation on several test grids are conducted. Results are presented for these cases in 2D and a cubic grid in 3D using a Runge‐Kutta time iteration for the smoothing operator until steady state is reached. © 2002 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 18: 179–192, 2002; DOI 10.1002/num.1002 相似文献
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Time-resolved measurements of the oxygen atom concentration during shock-wave initiated combustion of low-density (25 ≤ p ≤ 175 kPa) H2? O2? CO? CO2? Ar mixtures have been made by monitoring CO + O → CO2 + hv (3 to 4 eV) emission intensity, calibrated against partial equilibrium conditions attained promptly at H2:O2 = 1. Significant transient excursions (“spikes”) of [O] above constant-mole-number partial-equilibrium levels were found from 1400 to 2000°K for initial H2:O2 ratios of 16 and 10 and below ± 1780°K for H2:O2 = 6; they did not occur in this range for H2:O2 ± 4. Numerical treatment of the H2? O2? CO ignition mechanism for our conditions showed [O] to follow a steady-state trajectory governed by large production and consumption rates from the reactions with a pronounced maximum in the production term ka[H][O2]. The measured spike concentration data determine kb/ka = 3.6 ± 20%, independent of temperature over 1400 ≤ T ≤ 1900°K, which with well-established ka data yields This result reinforces the higher of several recent combustion-temperature determinations, and its correlation with results below 1000°K produces a distinctly concave upward Arrhenius plot which is closely matched by BEBO transition state calculations. 相似文献
100.
Four rhenium(I) chromophores attached to a dirhodium(n) core form a new hexametallic light-harvesting assembly as characterised by X-ray crystallography, UV-vis spectroscopy and electrochemistry. 相似文献