scholarly journals Effects of dissolved metal chlorides on the behavior of silica nanoparticles in aqueous media

2014 ◽  
Vol 12 (4) ◽  
pp. 480-491 ◽  
Author(s):  
Vladimir Gun’ko ◽  
Lyudmyla Andriyko ◽  
Vladimir Zarko ◽  
Andrij Marynin ◽  
Valentyn Olishevskyi ◽  
...  
Keyword(s):  
Zeta Potential ◽  
Aqueous Media ◽  
Salt Content ◽  
Silica Content ◽  
Correlation Spectroscopy ◽  
High Concentration ◽  
Screening Length ◽  
Photon Correlation ◽  
Metal Chlorides ◽  
Primary Particles

AbstractEffects of chlorides of univalent (LiCl, NaCl, KCl), bivalent (MgCl2, BaCl2) and trivalent (AlCl3) metals at different concentration (0.001–0.1 M) on the behavior of nanosilica A-200 (0.5–5 wt.%) in aqueous media are analyzed using photon correlation spectroscopy (particle size distribution, PSD), electrophoresis (zeta potential ζ), potentiometric titration (surface charge density), and estimation of screening length of primary particles and their aggregates. The zeta potential and the PSD are affected by silica content, pH, and concentration and type of dissolved salts. Smaller but more strongly hydrated Li+ cations caused stronger nonlinear dependences of the zeta potential on pH and salt content than Na+ or K+. This nonlinearity is much stronger at a lower content of silica (0.5–1 wt.%) than at C A-200 = 2.5 or 5 wt.%. At a high concentration of nanosilica (5 wt.%) the effect of K+ ions causes stronger diminution of the negative value of the zeta potential due to better adsorption of larger cations. Therefore, the influence of K+ on increasing screening length is stronger than that of Na+ for both primary nanoparticles and their aggregates. A similar difference in the ζ values is observed for different in size cations Ba2+ and Mg2+.

Unfolding of hemoglobin variants—insights from urea gradient gel electrophoresis photon correlation spectroscopy and zeta potential measurements

2004 ◽  
Vol 522 (2) ◽  
pp. 207-214 ◽  
Author(s):  
Jaydeep Bhattacharya ◽  
Ranjita GhoshMoulick ◽  
Utpal Choudhuri ◽  
Prantar Chakrabarty ◽  
Pranab K. Bhattacharya ◽  
...  
Keyword(s):  
Zeta Potential ◽  
Gel Electrophoresis ◽  
Photon Correlation Spectroscopy ◽  
Correlation Spectroscopy ◽  
Photon Correlation ◽  
Gradient Gel Electrophoresis ◽  
Hemoglobin Variants

scholarly journals Nanosized and Enhancement of Solubility Fisetin

2019 ◽  
Vol 7 (2) ◽  
pp. 6-10
Author(s):  
Muhammad Dzakwan ◽  
Eko Pramukantoro Ganet ◽  
Mauludin Rachmat ◽  
Saleh Wikarsa
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Photon Correlation Spectroscopy ◽  
Average Particle Size ◽  
Correlation Spectroscopy ◽  
Polydispersity Index ◽  
Average Particle ◽  
Polysorbate 80 ◽  
Photon Correlation ◽  
The Poor

Fisetin (3,3,4,7-tetrahydroxyflavone) is a natural antioxidant that has shown to posses anticancer, antioxidant and anti-inflammatory properties. However, the poor solubility leads to poor bioavailability and limits its development.The aim of the research is to investigate the effect of fisetin nanosuspension using a nanoprecipitation technique and additional stabilizers polysorbat 80, SLS, PVA and Eudragit on particle size average, polydispersity index and zeta potential.The suspensions of microcrystalline FIS were prepared by a nanoprecipitation technique with different proportion of stabilizers fixed. The nanosuspension produced was then characterized using Photon Correlation Spectroscopy (PCS) in  term of particle size distribution, polydispersity index, zeta potential and morphology nanosuspensiom (TEM). Result showed fisetin nanosuspension were successfully prepared by anti-solvent precipitation with additional stabilizer SLS and polysorbat 80. The nanosuspension containing polysorbat 80 showed smaller average particle size of 225.7 nm ± 1.31, a polydispersity index of 0.272 ±0.02 and zeta potential -39.3 ± 0.26 was obtained. Conclusion, FIS nanosuspension successfully prepared by nanoprecipitation tecnique with the polysorbate 80 as stabilizer and ethanol as solvent were spherical in shape..

scholarly journals Characterization of PF4-Heparin Complexes by Photon Correlation Spectroscopy and Zeta Potential

2017 ◽  
Vol 23 (7) ◽  
pp. 725-734 ◽  
Author(s):  
Sabrina Bertini ◽  
Jawed Fareed ◽  
Laura Madaschi ◽  
Giulia Risi ◽  
Giangiacomo Torri ◽  
...  
Keyword(s):  
Zeta Potential ◽  
Photon Correlation Spectroscopy ◽  
Correlation Spectroscopy ◽  
Photon Correlation ◽  
Heparin Complexes

scholarly journals From Femtoseconds to Hours–Measuring Dynamics over 18 Orders of Magnitude with Coherent X-rays

2021 ◽  
Vol 11 (13) ◽  
pp. 6179
Author(s):  
Felix Lehmkühler ◽  
Wojciech Roseker ◽  
Gerhard Grübel
Keyword(s):  
Time Scales ◽  
Free Electron Laser ◽  
Photon Correlation Spectroscopy ◽  
Signal To Noise Ratio ◽  
Coherent Scattering ◽  
Correlation Spectroscopy ◽  
X Rays ◽  
Photon Correlation ◽  
X Ray ◽  
Scattering Technique

X-ray photon correlation spectroscopy (XPCS) enables the study of sample dynamics between micrometer and atomic length scales. As a coherent scattering technique, it benefits from the increased brilliance of the next-generation synchrotron radiation and Free-Electron Laser (FEL) sources. In this article, we will introduce the XPCS concepts and review the latest developments of XPCS with special attention on the extension of accessible time scales to sub-μs and the application of XPCS at FELs. Furthermore, we will discuss future opportunities of XPCS and the related technique X-ray speckle visibility spectroscopy (XSVS) at new X-ray sources. Due to its particular signal-to-noise ratio, the time scales accessible by XPCS scale with the square of the coherent flux, allowing to dramatically extend its applications. This will soon enable studies over more than 18 orders of magnitude in time by XPCS and XSVS.

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