special issue | size and shape of particles in suspensions, emulsions… · · 2017-06-21particle...

the s

am

ple

Dynam

ic Im

age Analysis

Dynam

ic Im

age Analysis

CAMSIZER®

CAMSIZER XT

Sta

tic

La

ser L

ight Scattering

HORIBA LA-300

Dynamic Image AnalysisStatic Laser Light ScatteringDynamic Laser Light Scattering

Particle MeasurementAnalysis methods in a size range from 0.3 nm to 30 mm

ISSN 0949-6025 | Special Issue | Size and shape of particles in suspensions, emulsions, colloidal systems, powders, granules and bulk materials

SPECIAL

partIcle meaSuremeNt

Sta

tic

La

ser L

ight Scattering

HORIBA LA-950

Dy

nam

ic L

aser Light Scattering

HORIBA SZ-100

NEW

NEW

30 µm - 30 mm

1 µm - 3 mm

0.3 nm - 8 µm

10 nm - 3 mm

0.1 µm - 600 µm

EDITORIAL

Particle analysis methods in a measuring range from 0.3 nm to 30 mmOptimum solutions for a great variety of applications

Our range of instruments for particle characterization covers a measuring range from 0.3 nm to 30 mm. Based on different measurement techniques, they are used for the analysis of particle size and shape of suspensions, emulsions, colloidal systems, powders, granules and bulk materials.Dear Readers,

Customers and Business Partners

each particle analysis method has its typical application areas, but also advantages and disadvantages when compared to other tech-niques. In this special issue “particle measurement” of our customer magazine “the sample” we would like to introduce the product portfo-lio of retsch technology and, at the same time, give you an overview of the most important analysis meth-ods for particle size and shape.

In addition to the established analyzers HOrIBa la-950 and camSIZer, we are happy to present you two new instruments:the camSIZer Xt is based on the same measurement principle as the well-known camSIZer, but allows for wet or dry measurement of fine powders with particle sizes as low as 1 micron. the new Horiba SZ-100 analyzes size, zeta potential and molecular weight of nano particles with great flexibility, in low or high concentrations.

We hope that our comparison of methods as well as the presentation of our analyzers will give you some ideas of how to analyze your sam-ples more efficiently and reliably. maybe you will even find your own application among the many exam-ples presented in this issue?

We hope you enjoy reading this special edition of “the sample”!

Yours

Dr. Jürgen pankratzmanaging Directorretsch technology GmbH

a SuItaBle aNalYZer FOr eacH meaSurING raNGe

0.1 µm 600 µm

10 µm 4 mm

30 µm 30 mm

0.3 nm 8 µm

1 nmParticle size: 1 µm 1 mm 1 m

users can choose between various methods of particle size analysis which go beyond traditional, purely mechanical sieving. In this segment, retsch technology offers a wide product selection based on image processing techniques and laser diffraction methods. When looking for the method best suited for a particular application, a variety of criteria has to be taken into consideration. technical parameters, such as measuring range, resolution, reproducibility and detection efficiency, as well as investment and operating costs play an important role in this context. Newly developed instruments offer alternatives to established techniques and challenge well-proven methods.

SelectION crIterIa

Particle Size

the most important criterion for the selection of a suitable measurement tech-nique is the particle size to be measured. Static laser light scattering covers the widest measuring range from 10 nm to 3 mm. Dynamic laser light scattering, in contrast, is only suitable for measuring particles in the nanometer range. Optical image processing methods, just like sieve analysis, are typically used in a range from microns to centimeters.

1 µm 3 mm

10 nm 3 mm

20 µm 125 mm

Dynamic Image Analysis

CAMSIZER

CAMSIZER XT

Static Laser Light Scattering

LA-300

LA-950

Dynamic Laser Light Scattering

SZ-100

Sieve Analysis

Vibratory Sieve Shaker AS 200

Air Jet Sieving Machine AS 200 jet

■ Dry measurement■ Wet measurement

www.retsch-technology.com | 03

Particle analysis methods in a measuring range from 0.3 nm to 30 mmOptimum solutions for a great variety of applications

a cOmparISON OF meaSuremeNt tecHNIQueS

Performance FeatureDynamic Image

AnalysisStatic Light Scattering

Dynamic Light Scattering

Sieve Analysis

Analysis of nano particles x + ++ x

Reproducibility and repeatability ++ ++ + +

High resolution for narrow distributions

++ + - -

Particle shape analysis ++ x x x

Determination of molecular weight x x + x

Determination of zeta potential x x ++ x

Reliable detection of oversized grains

+ - - ++

Wet Measurement ++ ++ ++ +

Dry Measurement ++ ++ x ++

High measurement speed, short measurement times

+ ++ + -

Investment costs high high high low

Operating costs (work load) low low low high

·+++

++

++

+

+

·

·

++

++

++

++

++

+

+

++

++

++

++

+

+

·

++

++

++

+

+

+

·

·

Sample Volume

another crucial factor is the sample volume. to obtain sig-nificant and reliable results, it is essential to measure a representative sample amount. It usually takes at least a few thousand up to a few million particles, depending on the width of the particle size distribution, to obtain statisti-cally accurate results. Depending on the mean particle size, this can be from a few micrograms of nano particles to a few kilograms of gravel, coarsely broken ores or coal. the sampling and sample splitting processes are as impor-tant as the analysis itself, and should therefore be carried out with the same care. When using a microscope for auto-matic measurement and evaluation, only a small number of particles is analyzed; whereas dynamic image analysis or laser diffraction allow to measure 100,000 to a few mil-lion particles. laser diffraction instruments record the light

scattering pattern that is generated by the entire particle collective, calculating the size distribution on that basis (indirect measurement). Image processing techniques record the measured values of every single particle (direct size and shape analysis), calculating the size distribution on the basis of the individual values.

the difference between direct and indirect measurement methods and the number of detected particles determine the detection limits of the instruments: small amounts of “oversized” or “undersized” particles (<0.1 %) can be relia-bly detected with sieve analysis and dynamic image analy-sis but neither with laser diffraction nor with static micros-copy.

Retsch Technology offers individual application consultation which comprises an unbiased consideration of the pros and cons of the different techniques.

For more details on the measure-ment techniques as well as informa-tion on the different particle analyz-ers, please refer to the following pages.

highly suitable suitable suitable to a limited extent

not possible

camSIZer®

page 4-5camSIZer Xt

page 6-9HOrIBa la-950

page 10-13

HOrIBa la-300page 13

HOrIBa SZ-100page 14-15

Sieve Shakerswww.retsch.com

Quality control of bulk materials with the CAMSIZER®

the camSIZer has been used for the quality control of freely pourable bulk materials for more than 12 years. Over 500 installations around the globe document the success and the universal suitability of this measuring method. the main fields of application include: food (e. g. granulated chocolate, nuts, rice, or sugar), pharmaceutical products (e. g. pain tablets or cough medi-cine), fertilizer products (e. g. uncoated or coated fertilizer granulates, such as urea beads, nitrogen, potassium or phosphate based products), catalysts products (e. g. round beads or extrudates), and, finally, mass bulk goods (e. g. ceramic proppants, sand, salt, coal, ores, glass beads, and plastics).

compared to other methods, the camSIZer offers crucial advantages in the measuring range from 30 µm to 30 mm. On the one hand, the instrument is easy to operate, robust and almost maintenance-free. On the other hand, the user obtains measurement results with high reproducibility and resolution in a very short time of typically 2 to 3 minutes. the high resolution and short measuring time are achieved by the patented two-camera principle: one camera analyzes the finer particles with high resolution, whereas the other camera with its large field of view records simultaneously many and also larger particles at high detection efficiency.

DynAMIC IMAgE AnALySIS

| www.retsch-technology.com04

BeNeFItS

■ Dynamic Image analysis with patented two-camera-System (acc. to ISO 13322-2)

■ Wide measuring range from 30 μm to 30 mm

■ Detailed particle size analysis – results are stored in at least 1,000 size classes

■ particle shape analysis (e. g. for the detection of agglomerates, broken particles or contaminations)

■ Very short measurement time of 2 to 3 minutes

■ realtime results■ Highest precision and reproducibility■ results are 100% compatible to

sieve analysis and laser diffraction ■ Simple and comfortable operation■ Non-contact, non-destructive

measurement ■ calibration in seconds ■ Options:

autoSampler, Online version

www.retsch.com/camsizer

Dry measurement of powders and

granules

30 µm –––– measuring range –––– 30 mm

Dynamic Image AnalysisCAMSIZER®: more than 500 installations


applIcatION eXampleS

abrasives, carbon products, catalysts, coffee, fertilizer, food, glass/ceramics, metal powders,

pelletized carbon black, pharmaceutical products, plastics, polystyrene, refractories, salt,

sand, sugar, etc.

Determination of the coating thickness of pharmaceutical pellets and granules

many pharmaceutical agents are pro-duced in the form of pellets or gran-ules with a controlled release formula-tion. the size and shape of the mostly spherical particles are important parameters in the production process and are therefore carefully monitored to detect undersized and oversized grains, broken particles or agglomer-ates.

the parameters for the time release profile of the active pharmaceutical ingredient (apI) inside the human body are controlled via the size of the granules and the layer coating thick-ness. the release rate of the apI is affected by the particle surface. the larger the particle surface the faster the apIs are released. the release time increases with the thickness of the coating.

the granules are often coated with several layers, not only with the actu-al apIs but also with coatings resist-ant to gastric acid or with membranes which allow for a controlled release of the apIs. the camSIZer analyzes the coating thickness for a representative number of particles with an accuracy of 2 microns quickly and reproducibly.

this makes the camSIZer superior to methods such as sieving or microsco-py which either analyze many parti-cles with a poor resolution or only a few particles very accurately with a great expenditure of time. moreover, the camSIZer provides additional information about the particle shape, e.g. the sphericity of the particles.

the image shows pellets with different coating thickness. In cases where the difference in the coating thickness is extremely small, only the precise measurement of many particles allows a statistically accurate result.

the graphic shows the original material (red) and 2 batches of coated granules with a medi-um difference in the coating thickness of 4.5 microns (green and blue). the width of the distribution not only gives information about the mean diameter but also about the homoge-neity of the coating.

x [mm]

Q3 [%] q3 [%/µm]

1.6 1.8 2.0 2.2 2.4 2.6

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the camSIZer is also available with

an autosampler for automatic sample

feeding (see picture) or as online

version for process-integrated

measurements.


tecHNIcal Datameasuring principle Dynamic Image analysis

(ISO 13322-2)type of analysis dry analysis of powders

and granulesmeasuring range 30 µm to 30 mm measured properties particle size, shape,

density, transparency, and number

measuring time approx. 2 to 3 mins (depends on required measurement statistics)

Sample volume 100 mg - 25 kg measuring speed 60 images/s

each with more than 780,000 pixels

Width of analysis area 110 mm (FoV) resolution typ. 15 µm/pixel

the camSIZer is ce-tested and fulfills all relevant directives and standards.

Option 21 cFr part 11 compliant software IQ/OQ documentation

acc. to Glp/Gmp

13% coating

15% coating



BeNeFItS

■ Dynamic Image analysis with patented two-camera-System (acc. to ISO 13322-2)

■ Wide dynamic measuring range from 1 μm to 3 mm

■ Newly developed optical system with ultra-strong leDs for highest resolution and excellent depth of sharpness

■ reliable detection of smallest amounts of “undersize” and “oversize”

■ particle shape analysis (e.g. for the detection of broken particles, twinnings or aggregations)

■ Very short measurement time of 1 to 3 minutes

■ excellent reproducibility■ modular system X-change for dry

and wet dispersion■ measurement results are 100%

compatible to sieve analysis and laser diffraction analysis

www.retsch.com/camsizerxt

The quality control of fine powders can be improved substantially with the CAMSIZER XT: More precise and faster analysis of particle size and particle shape helps to improve product quality, reduce rejects and save costs.

the camSIZer Xt is an advance-ment of the well-proven optical measurement system camSIZer for finer samples. In addition to the newly developed optics with a high-er resolution it also features enhanced options for sample feed-ing. Fine particles tend to agglom-erate which makes it difficult to detect the geometric dimensions of each individual particle. It is there-fore beneficial to have various pos-sibilities of feeding the sample to the measurement area, finding for each material the best way to sepa-rate the agglomerates without destroying the primary particles. the camSIZer Xt provides flexible solutions: the free fall cartridge,

which provides the mildest disper-sion method for the material; the air pressure dispersion cartridge with adjustable pressure and varia-ble nozzle geometry; and, addition-ally, a wet module in which parti-cles are dispersed in liquids, option-ally by an ultrasonic probe.

thanks to the modular design of the camSIZer Xt (X-change-technology), changing between dispersion meth-ods is easy and comfortable.

Watch the video on www.retsch-technology.com/camsizerxt to see how easy the “X-Change” system works.

Measure- ment of fine powders, granules and suspensions

1 µm –––––––– measuring range –––––––– 3 mm

Dynamic Image AnalysisCAMSIZER XT: proven method – new measuring range

NEW



Modular design for optimum measurement conditions

plug-in cartridge “X-Jet”

plug-in cartridge “X-Fall”

module “X-Dry”

module “X-Flow”

Basic instrument

Wet measurementDry measurement

Air pressure dispersion gravity dispersion

Air Pressure Dispersion with “X-Jet”measuring range from 1 µm to 1.5 mm

the dispersion, i. e. the separation of the particles when passing through the measurement area, is a crucial precon-dition for a correct measurement of the particles. thanks to the flexible pres-sure adjustment of the “X-Jet” plug-in cartridge materials can be measured under optimum conditions. With the dynamic image analysis method it is possible to detect broken particles and agglomerates by analyzing the particle shape, and then adjust the pressure as required. the sample is collected in a vacuum cleaner after the measure-ment. If the sample material needs to be recovered for further analysis, an optional cyclone is available. although the air pressure dispersion accelerates the particles to up to 50 m/sec, the patented two-camera system ensures that wide particle size distributions as well as narrow, mono-modal samples below 10 microns are analyzed accu-rately.

gravity Dispersion with “X-Fall”measuring range from 10 µm to 3 mm

pourable, not agglomerated samples can be analyzed by using the “X-Fall” plug-in cartridge. In this mode the particles fall from the chute through the field of view of the two cameras accelerated by gravity. thanks to the low speed of the particles, the large field of view and the high frame rate, the detection efficiency is very high, even for large particles of e. g. 3 mm. Only a few coarser particles in the sample are sufficient for the reliable, reproducible detection. after the meas-urement the sample material falls into a collector box and is available for fur-ther analyses without loss or contami-nation.

Wet Dispersion with “X-Flow”measuring range from 1 µm to 600 µm

the wet module “X-Flow” analyzes samples in a range from 1 to 600 microns in suspensions or emulsions. an advantage of this module is the small required sample volume. a low particle concentration in the dispersion medium of, for example, 20 mg/l is already sufficient to detect enough particles for a reproducible result in only 1 minute.the measurement range of the “X-Flow” module starts at 1 micron. the camSIZer Xt also analyzes parti-cles larger than 1 mm without difficul-ty, provided they are kept suspended in the dispersion medium. Depending on the maximum particle size of the sample, measurement cells of up to 4 mm can be used. agglomerates can be further separated by an integrated ultrasonic probe.

the camSIZer Xt’s “X-change” system offers three alternative dispersion methods, allowing the selec-tion of the optimum method for each sample type.

x [µm]

q3 [%/µm]

0 1 2 3 4 5 6 7 8

45

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35

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abrasives (medium-sized and small

grit), detergent powder and raw

materials, fine sands and cement, fine

wood fibers, fine plastic fibers, metal

and ore powders, pharmaceutical

powders, granules and fine pellets,

plastic powders (also with electrostatic

charge), pulverized and granulated

food, etc.

the direct measurement method – which analyzes every single particle on each picture in real time – allows for the reliable detection even of very small amounts of oversized grains. the camSIZer Xt detects oversized parti-cles even if the fraction is considerably less than 0.1%, whereas the laser dif-fraction method needs at least 1% to 2%. thanks to the high resolution of the optics, Dynamic Image analysis with the camSIZer Xt allows for the separate resolution of narrow multimo-dal distributions. In contrast to laser diffraction analyzers, the camSIZer Xt is able to separate, for example, the size fractions in a particle mixture of 2.5 and 5 microns and to determine

Multimodal distributions

CAMSIZER XT: more precise size mea

the respective volumes. Dynamic Image processing analyzes each parti-cle with a resolution of approx. 1 micron, thus allowing for a much better resolution of narrow multimodal distributions than is achievable with laser diffraction.

the application example shows a mix-ture of polymer beads of 2.5 and 5 microns. the result of a laser diffrac-tion measurement would show a wide distribution with only one peak.

light source 1

sample flow

light source 2

zoom camera

basiccamera

+

The patented measurement principle

the patented measurement principle is fairly simple: Dispersed particles pass in front of two bright, pulsed leD light sources. the shadows of the particles are captured with two digital cameras. One camera is opti-mized to analyze the small particles with high resolution; the other camera detects the larger particles with good statistics, due to a large field of view. each camera is illu-minated by one leD with optimized bright-ness, pulse length and field of illumination. to cover a small measuring window of limit-ed space with two light sources, optics and cameras, the X-technology was developed: the optical paths of both cameras intersect in the measurement area. particle size and particle shape are analyzed with a user-friendly software which calculates the respective distribution curves in real-time.


Optical microscope

b/l

Q3 [%]

0.4 0.5 0.6 0.7 0.8 0.9

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breadth/length ratio

brokensphe-rical

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– measurement 1

– measurement 2

– measurement 3

– measurement 4

– measurement 5

x [µm]

Q3 [%]

0 50 100 150 200 250 300 350 400

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– width

– diameter of the coextensive circle

– length

– laser diffraction result



particle size analysis with the camSIZer Xt comprises recording the various dimensions of a particle. the example of cellulose fibers shows that the distributions of the diameter, the mean diameter and the length of the fibers are analyzed separately. the user obtains more detailed infor-

Non-round, broken particles are detected via the breadth/length ratio (b/l) or the symmetry. the series of measurements shows how an increas-ing amount of broken particles leads to an increase of the broken fraction in the b/l diagram. the original mate-rial is almost spherical, with a b/l ratio

surement with particle shape analysis

Particle size: exact length and width or just an “effective scattering cross section”?

Particle shape analysis

mation, thus getting a broader knowl-edge of the “size” of the cellulose fib-ers. this is not possible with other measurement methods such as, for example, laser diffraction, which only provide the “effective scattering cross section”.

of 0.95 (red curve). the increasing proportion of broken particles can be read directly from the amount at the threshold value of 0.95.

tecHNIcal Data

measuring Dynamic Image principle analysis

(ISO 13322-2)type of analysis analysis of fine

powders, granules and suspensions

measuring range “X-Dry” with “X-Fall”: 10 µm to 3 mm “X-Dry” with “X-Jet”: 1 µm to 1.5 mm “X-Flow”: 1 µm to 600 µm measured properties particle size and particle shapemeasuring time approx. 1 to 3 mins

(depends on required measurement statistics)

Sample volume <20 mg – 100 g (depends on sample and dispersion method)

measuring speed >275 images/sec. each with approx. 1.3 mpixel

Width of analysis area 20 mm (FoV) resolution 1 µm/pixel

the camSIZer Xt is ce-tested and ful-fills all relevant directives and standards.

Optional 21 cFr part 11 - compliant software

IQ/OQ documentation acc. to Glp/Gmp

camSIZer Xt basic camera

camSIZer Xt basic camera

STATIC LASER LIgHT SCATTERIng

Static laser light scattering (also known as laser diffraction) excels by a combination of extremely wide measuring range, simple oper-ation and high measurements accuracy.

an analysis with the laser granulometer HOrIBa la-950, including sample preparation, measurement and cleaning, only takes 1 minute. every step of the process is carried out fully automatically thanks to easily program-mable Standard Operating procedures (SOps).

With the la-950 particle size distributions from 10 nm to 3 mm can be measured without the need to switch the measuring range or change lens-es. the software allows comprehensive analyses and evaluations as required in science, research and development. all process steps can be automated in such a way that the la-950 is also suitable for quality con-trol routine measurements.

Due to these benefits, the la-950 is used in many different industries such as, for example, automotive, pigment and food, but application areas also include aircraft construction, pharmaceutics and desulfurization of flue gas in coal-fired power plants, to name but a few.

BeNeFItS

■ Single measuring range 10 nm 3 mm (no change of measuring range required)

■ complete analysis process only takes 1 minute

■ Wet and dry measurement■ modular design■ Intuitive software, including

optimization of measurement and evaluation parameters

■ effective dispersion inside the instrument

■ 21 cFr part 11 compliant software (option)

www.retsch.com/la950


10 nm –––––––––––––––––––– measuring range –––––––––––––––––––– 3 mm

Static Laser Light ScatteringLaser granulometer HORIBA LA-950: extremely wide measuring range

Wet and dry measurement


The unique optical system of the LA-950

the interaction of laser light and particles generates characteristic scattered light distributions. these are influenced by the size of the particles, their optical properties and the wavelength of the light. larger particles scatter the light in small angles. the HOrIBa la-950 is equipped with a 64-element detector for highest angular accuracy as well as with 23 detectors for light which is scattered sideways and backwards. this technology in combination with two light sources with different wavelengths allows for the unique measuring range from 10 nm to 3 mm.

Effective dispersion and measurement of nano materials

thanks to the integrated ultrasonic probe and the powerful circulation sys-tem, sample preparation can be carried out with the instrument for most mate-rials. the wide measuring range allows for the reliable characterization of nano materials. the application example shows the particle size distribution of a zinc oxide suspension. If the sample is analyzed without sample preparation, the result is a bimodal distribution with

2 peaks. the coarser peak represents agglomerates, the finer one the prima-ry particles. the use of ultrasound effectively dissolves the agglomerates within 2 minutes, ensuring that only the primary particles are measured with a size of 70 nm.

the accuracy in the nanometer range can also be demonstrated with certi-fied standard materials (see below).

Example: zinc oxide suspension Blue: no ultrasound, with agglomeratesGreen: 1 min. ultrasound red: 2 min. ultrasound, no agglomerates

Example: Duke Scientific Standards Blue: 30 nmred: 60 nmGreen: 100 nm


ceramics, cosmetics, emulsions,

food, metal powders, pharmaceutical

agents, pigments

tecHNIcal Data

measuring principle mie Scattering theory

according to ISO 13320 type of analysis dry and wet

measurementmeasuring range 10 nm to 3 mmmeasuring time ~1 minute (from filling

in the dispersion liquid to the following meas-urement with result display and subsequent flushing of the system)

measuring methods – manual flow cell

measurement – manual fraction cell

measurement (fraction cell and cell holder required)

– dry measurement (powderJet dry feeder required)

Sample volume approx. 10 mg – 5 g Dispersion – flow cell: media approx. 180 – 290 ml – miniflow:

approx. 30 – 55 ml – fraction cell: approx. 15 ml

Dispersion water, alcohol andliquid other organic solvents

Mirror with automatic adjustment

Measuring cell

Fourier lens

Fourier lens

Segmented multi-element-detector for forward scattering

4-channel detectors for side scattering

4-channel detectors for side scattering

Detectors for back scattering

Blue LED

Laser diode

Detectors for back scattering


x [nm]

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the software of the la-950 helps the user with the meth-od development and the selection of suitable evaluation parameters for unfamiliar sample materials. the module “Method Expert” guides the users in several, easily comprehensible steps through the different settings required for the measurement. automatic test measure-ments are carried out with varying settings for circulation speed, particle concentration and ultrasound.

the light scattering patterns of fine particles are not only described by the diffraction but also by the optical charac-teristics of the particles. these characteristics are refrac-tion index and absorbance. If the relevant literature does not provide any references, it is possible to obtain a suita-ble value by reverse calculation (R parameter). this involves a comparison of the light scattering pattern which was actually measured with a theoretical pattern which was calculated using defined optical constants.the quality of the evaluation can be judged by the match between these patterns (see graphic). the congruence

can be quantified with the r parameter. the “method expert” helps the user to determine the refraction index with the best r parameter. With this procedure it is possible to obtain optimum results even with unknown materials or mixtures.

Software and “Method Expert”

poor evaluation: actual light scattering pattern (blue) and reverse calculated (theoretical) light scattering pattern show great differences.

Good evaluation: actual and theoretical light scattering pattern are mostly congruent.

application example:

Desulfurization of flue gas in coal-fired power plantslegal requirements and regulations are often the reason for routine particle size analyses in the context of process and product monitoring. a typical example is the removal of polluting sulfur compounds (SO2 and SO3) from the flue gas of power plants. During the desulfurization of flue gas in coal-fired power plants it is important to continuously monitor the particle size distribution of the resulting calci-um sulfate to ensure a smooth and effective process.

this example shows the suitability of the la-950 analyzer for optimum proc-ess monitoring. It not only helps to

comply with the regulations for the prevention of air pollution but also guarantees trouble-free and cost-effi-cient operation.


1.60 1.63 1.66 1.69 1.72

0.179

0.168

refraction index

R p

ara

mete

r

the better the match between the measured light scattering and the result of the reverse calculation, the more accurate is the evaluation. a low r parameter (here at a refraction index of 1.66) indicates the optimum evaluation parameters.

1 10 20 30 40 50 60 70 80 87

10

1

0.01

0.0001

measurement channels

inte

nsi

ty

1 10 20 30 40 50 60 70 80 87

10

1

0.01

0.0001

measurement channels

inte

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ty

x [µm]

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HORIBA LA-950: precise and flexible

NEW

the la-300 is the compact alternative to the la-950. With a measuring range from 100 nm to 600 microns for wet measurements, it is suitable for many dif-ferent applications. the small footprint allows for variable sites of operation. effective dispersion in the la-300 is provided by a powerful circulation system with integrated ultrasonic bath. the la-300 is optionally available in an “organic” version which is suitable for measurements in most dispersion liquids (water, alcohol, organic solvents).

HORIBA LA-300 – the compact alternative

Laser granulometer LA-300www.retsch.com/la300


Suitable sample feeding for every application

Fraction Cellthe fraction cells of the la-950 are suitable for the particle size distribution analysis even of very small amounts of valuable sam-ple materials. they are also ideal to analyze dispersions in expensive or harmful media. the required liquid volume lies between 7 and 20 ml. In the fraction cell, the sample is homogenized with a small magnetic stir-rer.

Miniflow Modulethe miniflow unit also reduces the required sam-ple amount and liquid vol-ume. compared to 200 – 350 ml dispersion liquid required for the standard version, miniflow only needs 35 – 55 ml. None-theless, it provides all the options of the standard cir-culation system, such as automatic filling, variable stirring speed, ultrasonic probe and automatic flush-ing.

Paste Cellthe paste cell is suitable for measuring particle size distributions in highly vis-cous media which cannot be recirculated in a circula-tion system such as, for example, resins, oils or phthalates. the sample is placed as a thin film between two glass plates and inserted into the ana-lyzer.

Autosamplerthe autosampler automati-cally feeds 24 samples one after the other to the ana-lyzer. It is suitable for dry samples which are meas-ured in wet dispersion. the Slurry Sampler accommo-dates up to 60 previously dispersed samples (suspen-sions or emulsions) which are allocated for successive measurements.

Powder Jetthe dry powder feeder “powder Jet” allows for particle size distribution analysis of dry powders and granules in a size range from 100 nm to 3 mm. agglomerates are gently dispersed via a Venturi nozzle, ensuring that the results are comparable to those of wet measurements. the laminar stream of particles effectively prevents dep-ositions and contaminations. De-agglomeration is achieved by a dispersion pressure varying between 0 and 4 bar without particles being destroyed.


DynAMIC LASER LIgHT SCATTERIng

the SZ-100 measures particles down to the nanometer range, both with extreme-ly high and extremely low sample con-centrations. this newly developed analyz-er is used in the fields of bio- and nano-technology (e.g. nanoceramics, nano-metals) and for protein analyses. the HOrIBa SZ-100 provides excellent meas-urement results and features a wide measuring range from 0.3 nm to 8 microns. the instrument not only meets the requirements of modern labo-ratories but is also perfect for quality control at production facilities.

In the nanomaterial and biomaterial fields, raw-material particle size and zeta potential have a significant influence on product performance and properties. the

The new compact nano particle analyzer HORIBA SZ-100 was designed for particle size measurement down to the nano range as well as for the determination of zeta potential and molecular weight.

key to ensure high product performance is to control the quality of nano particle raw materials. the instruments conven-tionally used in laboratories to analyze ultrafine particles require operator exper-tise and involve complex operations. With the SZ-100 an advanced analyzer has been introduced which is easy to employ for routine measurements, and yet can analyze low-concentration ultrafine parti-cles with highest accuracy.

With these functions, the SZ-100 is a modern, high-performance analyzer suit-able for r&D applications. thanks to the comfortable operation, it is not only ideal for use in laboratories but also for quality control in the production process.

BeNeFItS

■ extremely wide measurement range from 0.3 nm – 8 μm

■ Samples ranging from low ppm-order concentrations to 40 Vol%

■ Flexible optics with measurements at 90° or 173° scattering angle

■ temperature-controlled measurement chamber

■ easy operation, no cleaning or maintenance required

■ measurement of zeta potential ■ Determination of molecular weight

and 2. virial coefficient■ rapid analysis (2 min)■ Simple, intuitive software,

21cFr part11 conformity (option)■ Highest resolution and precision■ compact design allows for installa-

tion in any laboratory environment

www.retsch.com/sz100


0.3 nm ––––––––––––– measuring range––––––––––––– 8 µm

Dynamic Laser Light ScatteringPCS Particle Analyzer HORIBA SZ-100: the new 3-in-1 system

Particle Size, Zeta Potential and Molecular

Weight

NEW

DynAMIC LASER LIgHT SCATTERIng


colloidal metals and metal

oxides, liposomes,

proteins

tecHNIcal Data

Particle size: measuring principle photon correlation

Spectroscopy (pcS) acc. to ISO 13321

measuring range 0.3 nm – 8 µm

Molecular weight:measuring principle Debye plot method

(static light scattering)measuring range 1 x 103 - 2 x 107 g/mol

Particle size / molecular weight: measuring time approx. 2 min under

standard conditionsmeasuring cells various measuring cellsSample volume 12 µl – 1.2 ml mini-

mum, depending on type of measuring cell

Dispersion liquid water, alcohol, organic solvents

Zeta potential:measring laser Doppler electro-principle phoresismeasuring range -200 mV - +200 mVmeasuring time approx. 2 min under

standard conditionsmeasuring cells disposable cells with

electrodesSample volume 100 µlDispersion liquid water, alcohol, organic

solvents

Measuring Principle Dynamic Laser Light Scattering

Size analysis of liposomes

Zeta potential of a nano SiO2 dispersion

the SZ-100 detects light scattered by particles at 90° or 173° angle, depending on the concentration. ultrafine particles suspended in a liq-uid medium are constantly in motion (Brownian motion). Hence, the inten-sity of the scattered light is not con-stant. If the particles are small, they move with higher speed so that the measured signal varies rapidly. larger particles move more slowly so that

the measured signal remains stable for a longer period of time. the time dependent fluctuations of the light scattering signal can be evaluated via a so-called autocorrelation function from which the particle size is calcu-lated.the SZ-100 is ideally suited for the characterization of, for example, pro-teins, liposomes, colloidal metals and metal oxides.

liposomes are natural or artificially produced two-layer vesicles with walls of phospholipids. they are mainly used in pharmaceutics and cancer therapy as agent carriers. the typical particle size is smaller than 1 micron and has a

decisive influence on the agent’s trans-port and release. Dynamic light scat-tering is the ideal method to measure the size of liposomes.

For the zeta potential measurement the sample is filled into special cells with electrodes. an electric field is set up inside the cells in which the particles move according to their surface charge. a strong surface charge leads to a movement of the particles which can be quantified and measured via fluctua-tions of the scattered light. the meas-urement of the zeta potential allows for an estimation of the stability of the dis-persion, as strong surface charges lead

to the repulsion of the particles thus preventing agglomerations.

the example shows the zeta potential measurement of a nano SiO2 disper-sion with different pH values. With a pH value of 4, the zeta potential is 0 (isoelectric point). With a zeta poten-tial >+30 mV / <-30 mV, a dispersion is generally called stable.

LinseLaser

Rückwärts-detektor

90°-Detektor

Streulicht

Küvette

LinseLaser

Rückwärts-detektor

90°-Detektor

Streulicht

Küvette

Partikel in Brown‘scher

Bewegung

Einfallender Strahl

Streulicht

PMT (Photomultiplier)

Verstärker

Digitaler Korrelator

Rear detector (PMT)

Particle diameter(high-concentration samples)

Side detector (PMT)

Particle diameter(low-concentration samples)

Molecular weight measurement

Forward detector (PMT)

Zeta potentialmeasurement

Cell

Modulator

Reference beamParticle

Laser light source Transmitted light monitor (PD)

ElektrodeLaser Transmissionsmessung

Modulator

Referenzstrahl

Partikel

Küvette

Vorwärtsdetektor

Zetapotential-messung

Rear detector (PMT)

Particle diameter(high-concentration samples)

Side detector (PMT)

Particle diameter(low-concentration samples)

Molecular weight measurement

Forward detector (PMT)

Zeta potential measurement

Cell

Modulator

Reference beamParticle

Laser light source Transmitted light monitor (PD)


the autocorrelation function (left) provides the basis for the determination of the intensity-based particle size and the polydispersity index. With the mie-theory-based evaluation, the data are converted into a volume-related distribution (right)

x [µs]

1 10 100 1,000 10,000

1.2

1.0

0.8

0.6

0.4

0.2

0.0

delay time

au

toco

rrela

tion

fu

nct

ion

[mV]

2 3 4 5 6 7 8 9 10

6050403020100

-10-20-30-40-50-60

pH value

zeta

pote

nti

al

x [nm]

Q3 [%] q3*

10 100 1,000

100

90

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3

2

1

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particle size

perc

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olu

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rela

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req

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Retsch Technology The Specialists in Particle Measurement Technology

retsch technology’s core competence is the combination of innovative particle characterization technologies with a maximum of operating convenience.

the line of products for optical particle analysis covers a size range from 0.3 nm to 30 mm. Significant analyses of particle size and parti-cle shape in suspensions, emulsions, colloidal systems, powders, gra-nules and bulk materials can be carried out on the basis of different measuring techniques

together with our sister company retsch GmbH, we offer a complete selection of products for sample preparation (grinding, sample divisi-on, analytical sieving).

■ Personal Consultationretsch technology works with a global network of distributors who provide expertise and application support.

■ Product DemonstrationsWe demonstrate our equipment in our own application laboratory or at your premises. please contact our sales team for further information.

RETSCH TECHnOLOgy

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97.P

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Retsch Technology gmbHrheinische Straße 4342781 Haan, Germany

phone +49 (0)2129/5561-0Fax +49 (0)2129/5561-87

e-mail [email protected] www.retsch-technology.com

Visit our

website for

brochures,

videos and

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reports

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special issue | size and shape of particles in suspensions, emulsions… · · 2017-06-21particle...

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