PLUS. Zeta/Nano Particle Analyzer

Transcription

1 PLUS Zeta/Nano Particle Analyzer

2 -100 m The NanoPlus Zeta-Potential & Particle Size Analyzer Features ELSZ-1000 series ZETA-POTENTIAL & PARTICLE SIZE ANALYZER of ink for inkjet printer (Yellow) Concentration range -200~200mV 0.6~10000nm ~ mv) oncentration dependence of latex suspension FEATURES Accurate measurement for dilute and concentrated suspension Easy-to-use cells and user friendly software Reliable measurement based on electroosmosis profile estimation Evaluation of surface charge on solid-plate, film and etc. Micro-volume disposable cell Wide size range(0.6nm~10000nm), wide concentration range ( %~40%) Combination of linear and log-scale correlator covers various sample characteristics Well-established technique comform to ISO : analysis-photon correlation spectroscopy Micro-volume cell CELL LINE-UP distribution of thiamine prob(%) solid content ave,diameter 0.6nm diameter nm Sizing Standard cell (Flow cell) Micro volume disposable cell High concentration cell Low conductivity cell Solid sample cell Sizing cell Disposable cell Micro volume cell Flow cell diameter(nm)

3 High-resolution analysis of zeta-potential Resolution of zeta-potential measurement is so high as to enable multi-component analysis owing to calculation of correlation and FFT calculation with the software. Mixture of five polystyrene latex of different particle size is measured. Five spectrum correspounding to each latex are appeared. of five components are in the range of -45mV to -107mV, and they show good cosistent with that from individual measurement. Zeta potential of Polystyrene latex mixture Evaluation of surface charge of solid plate Using the solid-plate sample cell, surface charge of solid sample can be estimated (1)Zeta potential of glass plate charged to negative (Blank) surface charge = -58.4mV (solvent:1mm NaCl solution) (2)Surface charge of glass is neutralized by positive charge of cethyl trimethyl ammonium bromide (CTAB) surface charge = +1.3mV (solvent:1mm NaCl solution containing 1 x 10-5mol/l CTAB) (3)Surface charge of glass change to positive owing absorption of excess CTAB surface charge = +48.4mV (solvent F1mM NaCl solution containing mol/l CTAB)

4 Evaluation of dispersion stability by zeta-potential/particle size As the absolute value of zeta-potential is larger, general colloidal particles show good dispersibility, as the electrostatic repulsion becomes stronger. As the zeta-potential is close to zero, they become so unstable as to be likely to aggregate. Typical NanoPlus Applications Neutralization of charge Nano Material / Nano Technology Charge (Dispersion Stable) (Unstable Aggregation) As the ph value of the solution changes from acidic to alkaline values, alumina particles show a large change of the zeta-potential from plus to minus values. It can be seen that they have the isoelectric point to indicate the zero zeta-potential at around ph9. In the ph range where the absolute value of zeta-potential is large, their average particle size is small, and it can be seen that dispersion stability of the particles is good due to electrostatic repulsion. On the other hand, it can be seen that particles aggregation to be large in the average particle size, resulting in instability, in the area around the isoelectric point. σ-zeta potential Researches for fuel cells (carbon nanotube, fullerene, nano material, etc.) and for nano-bio (dendrimer, DDS, nano-capsule, etc.) Semiconductor Researches for clarification of deposition mechanism of foreign matters on silicon wafer surfaces, and interactions among abrasives, additives and wafer surface Medicine and food Researches for control of dispersion and aggregation of emulations (foods, perfumes, medicines and cosmetics), for functionality of protein, for cintrol of dispersion and aggregation of ribosome, and for functionality of protein, for control of dispersion and aggregation of ribosome, and for functionality of surface active agents (micelle) Ceramic and color material σ-diameter Resarches for control of surface reforming, dispersion and aggregation of ceramics(silica, alumina, titanium oxide, etc.) and inorganic sol, control of dispersion and aggregation of pigments),and for adsorption of collector of floating ores Polymer and chemical Researches for control of dispersion and aggregation of emulsions(paints and adhesives), control of surface reforming of latex(for medicines and industrial use), and for functionality of electrolytic polymers (polystyrene sulfonate, polycarboxyloic acid,etc.) Control of paper and pulp manufacturing process, and researches for pulp additives

5 The NanoPlus Zeta-Potential & Particle Size Analyzer Principle of Zeta-Potential Measurement In most cases, colloidal particles posses an either positively or negatively electrostatic charge. Having electrical fields applied to that particle dispersion, the particles migrate to oppositely charged direction. Upon particles being irradiated in migrating, scatter light causes Doppler shift depending upon electrophoresis mobility. ELSZ-1000 software calculates Doppler shift amount followed by electric mobility and zeta potential by combining heterodyne system and photon correlation method to perform Fourier transform (FFT) of obtained correlation function. v Doppler shift Velocity of particle movement Refractive index Viscosity v = 2Vn sin( /2)/ U = V/E = 4 U/... Smoluchowski equation Slipping level Detect angle Wavelength of incidence light Electrophoretic mobility Major part of medium Ion diffuse layer Fixed layer Colloidal particle Electric field Dielectric constant Electrophoresis Incident beam Concept of FST method By conventional method, scattered light from concentrated suspention can not be measured correctly due to multiple scattering (A). FST method developed recently detects the scattering light at forward direction through the transparent electrode. Optical path lengh of its detection is minimized to reduce the influence of multiple scattering. Thus, it can perform zeta-potential measurement of concentrated suspension with high accuracy (B). FST*: Electrophoretic mobility measurement of concentrated suspension using Forward Scattering through Transparent electrode. * patent pending Cell Transmission Scattering Incident beam Scattering Determination of true electrophoretic mobility (A) Standard cell (B) High concentration cell When measurement of electrophoresis is actually taken, electroosmotic current is generated in the cell due to electric charge on the cell wall. The electroosmotic current means a phenomenon that, in the case of the cell wall charged to minus, ions and particles of plus electric charge gather together around the cell wall, so that the solution located around the wall faces migrates toward the minus electrode direction during electrophoresis and the solution located at the cell center follows in the opposite plus electrode direction to compensate the flow in the plus electrode direction. Accordingly, electroosmic current is added to the apparent electrophoreis of particles observed. The ELSZ-1000 series apparatuses are designed to measure the electrophoretic mobility at severall points in the cell to thereby obtain a position not influenced by the electroosmotic current, i.e.static surface,and then calulate the true mobility at the position. As a result, the moblity can be measured at high accuracy, even if the electroosmotic profile of the system is asymmetrical due to adsorption or sedimentation of the sample. Principle of particle sizing Particulates dispersed in a solution are normally performing the Brownian motion. The motion is slower as the particles are larger and is faster as the particles are smaller. This principle is applicable namely when laser beams are irradiated to particles under the Brownian motion, scattered light from the particles shows fluctuation corresponding to individual particles.the fluctuation is observed according to the pinhole type photon detection method, so that particle size and particle size distributions are calculated. G 2 ( ) = 1+ (G 1 ( )) 2 G 1 ( ) = exp(-dq 2 ) d = kt/3 D... Stokes-Einstein equation cell wall cell wall Stationary layer apparent mobility at position (Z) True mobility electroosmosis flow at position (Z) G 1 ( ), G 2 ( ): Secondary and primary auto-correlation function(acf) : Diffusion coefficent : Scattering vector : Correlation time : Hydrodynamic diameter Incident beam APD(Avalanche Photo Diode) : Boltzmanns constant : Absolute temperature : Viscosity of medium Measurement cell Pinhole 1 Pinhole 2 (Colloid particle in Brown motion) Difference of scattering intensity and autocorrelation function(acf) between various sized particles Intensity Intensity Intensity and ACF of small particles Fluctuation of scattering light T Scattering light fluctuate fiercely Intensity and ACF of large particles Fluctuation of scattering light T Scattering light fluctuate moderately ACF The smaller particle is, the quicker ACF is decaying Correlation time ACF The larger particle is, the slower ACF is decaying Correlation time

6 Component NanoPlus-1 Particle Size Analyzer, Computer, Monitor, Size Cell NanoPlus-2 Zeta Potential Analyzer, Computer, Monitor, Flow Cell, Disposable Cell Principle Photon Correlation Spectroscopy Laser Doppler Method NanoPlus-3 Particle Sizing & Zeta Potential Analyzer, Computer, Monitor, Size Cell, Flow Cell, Disposable Cell Laser Doppler Method & Photon Correlation Spectroscopy Light Source Semiconductor Laser Semiconductor Laser Semiconductor Laser Detector Avalanche Photodiode Avalanche Photodiode Avalanche Photodiode Cell/Sample Volume [Size] Glass Cell(0.9mL~) [Zeta] Flow Cell(0.7mL~), High Concentration Cell(0.6mL~), Disposable Cell(130μL~) [Size] Glass Cell(0.9mL~) [Zeta] Flow Cell (0.7mL~), High Concentration Cell(0.6mL~), Disposable Cell(130μL~) Condensation Range [Size] : to 40% [Zeta] to 40% [Size] : to 40% [Zeta] to 40% [Zeta] -200 to 200mV, [Mobility] Measure Range [Size] :0.6nm to 10μm -20x10-4 to 20x10-4 cm 2 /Vs Operation 15 to 35 C 15 to 35 C 15 to 35 C Electricity Requirement AC V, 50/60Hz AC V, 50/60Hz AC V, 50/60Hz Dimention 380(W) x 600(D) x 210(H) mm 380(W) x 600(D) x 210(H) mm 380(W) x 600(D) x 210(H) mm Weight Approx. 22kg Approx. 22kg Approx. 22kg Data Processing Desk Top PC, Windows 7 Desk Top PC, Windows 7 Desk Top PC, Windows 7 Function Principle Auto-Titrator Automatic perform liquid titration for zeta potential measurement Automatic ph control of liquid suspension Operation Temperature 15 to 35 C Electricity Requirement AC V, 50/60Hz Dimention 250(W) x 310(D) x 290(H) mm Weight Approx. 7kg