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Electrophoretic light scattering

Electrophoretic Light Scattering (ELS) is a technique used to measure the electrophoretic mobility of particles in dispersion, or molecules in solution. This mobility is often converted to Zeta potential to enable comparison of materials under different experimental conditions. Electrophoretic light scattering (ELS) offers users fast testing of the electrophoretic mobility of particle.

Differential Scanning Calorimetry, Dynamic Light Scattering, Electrophoretic light scattering, Empyrean, MicroCal, Nanosight, Particle concentration, Particle shape, Particle size, Tech Talk, X-Ray Diffraction (XRD), Zeta potential, Zetasizer »

[24 Oct 2018 | ]

Liposomes have been attractive delivery systems for decades due to their composition of natural biological lipids and structural resemblance to cell membranes suggesting metabolic compatibility, low toxicity, biocompatibility and lack of a strong immune response1.  They are comprised of spherical vesicles with an aqueous core enclosed by one or more phospholipid bilayers or lamellae and are frequently classified based on their size, polydispersity, and number of bilayers2. Control over these parameters has remained a challenge with most preparation methods and is further accentuated when moving from a laboratory to industrial …

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Binding affinity and Kd, Chemical identification, Differential Scanning Calorimetry, Dynamic Light Scattering, Electrophoretic light scattering, Elemental analysis, Elemental quantification, Empyrean, Epsilon, Image Analysis, Isothermal Titration Calorimetry, Laser Diffraction, Malvern Panalytical Events, Mastersizer, MicroCal, Microcalorimetry, Morphologi, Particle shape, Particle size, Tech Talk, X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Zetasizer »

[19 Oct 2018 | ]

On October 2, 2018, we held a seminar entitled “Overcoming Characterization Challenges in Drug Formulation” in the Boston area.  It was a great opportunity to meet with many pharmaceutical scientists in the area and learn about their challenges and concerns.  The presentations addressed a number of topics of interest, from stability of formulations, trace phase and impurity detection, deformulation, root cause analysis, to optimizing small molecule candidate screening.  There were great questions from the audience, so we rounded up several questions and answers here to share.
How does the Mastersizer 3000 see …

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Dynamic Light Scattering, Electrophoretic light scattering, Particle size, Tech Talk, Zeta potential, Zetasizer »

[15 Oct 2018 | ]

The new ZS Xplorer software is here!
Modern, flexible and different from the classic Zetasizer software, the novel ZS Xplorer interface was developed specifically for the latest generation of Zetasizer systems: the Zetasizer Pro and the Zetasizer Ultra. If you missed the launch, check out the exciting launch recording and Q&A session.
In order to help you easily adapt to the new interface, here are a few commonly encountered tips to help you become familiar with the entirely new software architecture. The main difference is that data are now saved in one …

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Dynamic Light Scattering, Electrophoretic light scattering, Malvern Panalytical Events, Meet the Experts, Molecular size, Molecular weight, Particle size, Protein Aggregation, Protein Mobility, Static Light Scattering, Tech Talk, Zeta potential, Zetasizer »

[12 Oct 2018 | ]

Join us for the next User group meeting!
User Group Meeting Announcement 19 Oct 2018 1pm-4pm EDT

We are pleased to announce the first virtual Zetasizer User Meeting ZUM-1! This initiative is an effort to foster the diffusion of knowledge and experience between our support group and those researchers that regularly evaluate light scattering data from the Zetasizer. The Zetasizer Users Community is invited to present and share data with specific questions. Get live feedback from our panel of experts.
The meeting will be live-streamed via Webex and is limited to 3.0 hours. …

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Electrophoretic light scattering, Meet the Experts, Protein Aggregation, Protein Mobility, Zeta potential, Zetasizer »

[3 Oct 2018 | ]

Debye Screening – what is it?
 
In colloidal samples (and this spans the whole range from molecules in solution to particles in a dispersion) the movement of and forces between objects are often governed by the charge affecting neighbors. When we measure zeta potential (by electrophoretic light scattering), the determination of the effective charge of particles is really what is probed. In other words: zeta potential (or electrophoretic mobility) is a measure of how the charge of a particle/molecule is influencing the movement of another particle/molecule. The full potential as a …

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Chemical identification, Corporate, Dynamic Light Scattering, Electrophoretic light scattering, Morphologi, Particle shape, Raman spectroscopy, Zeta potential, Zetasizer »

[20 Sep 2018 | ]

Guest blog written by Chris Langley, Senior Sector Manager at DCA Design International Ltd.
Malvern Panalytical in conjunction with DCA recently received two awards for the Morphologi (4 and 4ID) and Zetasizer (Ultra and Pro) at the prestigious Red Dot 2018 product design awards. The distinction ‘Red Dot‘ is recognized internationally as one of the most sought-after seals of quality for good design.
The Red Dot Award jury comprises some 40 experts from around the world, who discuss, evaluate and test every single entry, live and on site, in a process lasting several …

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Customer experience, Electrophoretic light scattering, Meet the Experts, Zeta potential, Zetasizer »

[5 Sep 2018 | ]

How can we obtain the applied field strength?
When performing electrophoretic light scattering (ELS) measurements, the sample is exposed to an externally applied electric field, and we observe the extra movement that the particles undergo as a result of the applied field with the changes in the phase difference between the un-scattered reference laser beam and the scattering from the particles. The electrophoretic mobility µ is the particle velocity v divided by the electric field strength E, where the field strength is the applied voltage over the distance between the electrodes [typically …

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Dynamic Light Scattering, Electrophoretic light scattering, Malvern Panalytical Events, Particle size, Zetasizer »

[9 Aug 2018 | ]

Launching the latest Zetasizer in Mexico!
 
June was a special month at our Mexico City office. We held a specific launch party organized for the latest addition to our Zetasizer family of instruments – the Zetasizer Pro and the Zetasizer Ultra. One of the groundbreaking novelties in the new system is adaptive correlation, a new method to perform dynamic light scattering (DLS) measurements, where rapid correlation functions are classified as being steady state or transient. Steady-state data sets describe particles that are consistently part of the measurement volume and hence characteristic of …

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Electrophoretic light scattering, Malvern Panalytical Events, Meet the Experts, Molecular size, Nanoparticle Tracking Analysis, Nanosight, Particle concentration, Particle size, Zeta potential, Zetasizer »

[19 Jun 2018 | ]

I presented a new webinar focusing on “A basic introduction to Electrophoretic Light Scattering (ELS)“. In this presentation, I explained the importance of Zeta potential measurements for colloidal dispersions and how it is determined using ELS.
As you certainly know, Electrophoretic Light Scattering (ELS) is a technique used to measure the electrophoretic mobility of particles or molecules in solution. This measurement is used to determine Zeta potential, which is a measure of the electrostatic or charges repulsion/attraction between particles and is a predictor of emulsion and dispersion stability. Zeta potential is …

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Dynamic Light Scattering, Electrophoretic light scattering, Particle size, Tech Talk, Zeta potential, Zetasizer »

[31 May 2018 | ]

How good can a gold standard be?
 
When performing dynamic light scattering (DLS) measurements, we sometimes encounter especially nice data. An interesting issue to consider is the level of data quality one can expect to achieve, under ideal circumstances, when all other interferences are minimized. This is especially relevant at the smaller nanoscale where fewer standards are available, and to those who have less practical experience with sizing colloidal nanoparticles by DLS. How monodisperse can a good sample be? What are achievable polydispersity index (PDI) values to aspire to?
What is the …

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Corporate, Dynamic Light Scattering, Electrophoretic light scattering, Molecular size, Molecular weight, Particle concentration, Particle size, Zeta potential, Zetasizer »

[23 May 2018 | ]

Where is the Zetasizer used?
 
For around two decades, the Zetasizer range has been the de facto standard for performing dynamic light scattering (DLS) measurements on a wide range of particles and materials.
Today’s launch of the Zetasizer Pro and Zetasizer Ultra – which took place earlier today on May 23rd, 2018 – provides a good reason to summarize the key application areas for light scattering technology: both dynamic and electrophoretic! Where are these Zetasizers used? Where can we find them, in the real world?
Below is a list of key application focus areas:

Bioscience and biopharmaceuticals: …

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Electrophoretic light scattering, Tech Talk, Zeta potential, Zetasizer »

[6 Mar 2018 | ]

Will the zeta potential of my vesicles vary in different buffers?
 

The short answer is: Yes, it will. In select cases, the value of the measured zeta potential may remain close to the same. However, that is the exception rather than the rule. This is no different for vesicles than for other nanoparticles, biomolecules, polyelectrolytes, etc.
How does zeta change with salt concentration?
The zeta potential of a colloidal particle in solution is a description of the overall effective net charge of the particle under the sample system conditions. Thus the effective net …

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Dynamic Light Scattering, Electrophoretic light scattering, Inside Malvern Panalytical, Zeta potential, Zetasizer »

[21 Dec 2017 | ]

On the 20th December 1977 (40 years ago) the Royal Radar and Signals Establishment (RRSE) and Malvern Instruments received the coveted MacRobert Award for the development of the Malvern Correlator.  This was fundamental to the development of Photon Correlation Spectroscopy (PCS) and the evolution of the Zetasizer product line. The MacRobert award is the UK’s longest-running and most prestigious national prize for engineering innovation. Other past winners include engineers behind innovations such as the Pegasus jet engine, catalytic converters, the roof of the Millennium Dome and intelligent prosthetic limbs.
The concept …

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Electrophoretic light scattering, Tech Talk, Zeta potential, Zetasizer »

[5 Sep 2017 | ]

Zetasizer: What is the zeta potential deviation?
 
The Malvern Zetasizer software report for zeta potential shows a parameter that is called Zeta deviation. This parameter is shown directly below the mean Zeta potential.

The mean zeta potential is derived from the fast field reversal (FFR) phase analysis light scattering (PALS) technique.
The fast field reversal provides a single number from the analysis. This single number is the mean zeta potential. The slow field reversal [also known as SFR] can be used to determine the zeta distribution, a distribution of different charge values from …

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Dynamic Light Scattering, Electrophoretic light scattering, Laser Diffraction, Particle size, Tech Talk, Zeta potential, Zetasizer »

[3 Aug 2017 | ]

Intralipid-Lipid emulsions

Lipid emulsions are administered intravenously for a variety of purposes:

To help feed patients with temporary difficulty in ingesting food orally
For better transport of lipophilic drugs (fat-friendly active ingredient (API) which is not soluble in water)
For controlled release of drugs (size related to uptake and retention)
To decreasing adverse reactions to drugs
To improve targeting of drugs
In emerging gene therapies for cellular and gene delivery, and personalized medicine

Control and understanding of colloidal properties – such as droplet size and zeta potential – enable the design and optimization of appropriately stable emulsions. The …

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Electrophoretic light scattering, Meet the Experts, Protein Mobility, Zeta potential, Zetasizer »

[27 Jul 2017 | ]

Nanomaterial isoelectric points IEPs
 
In a recent webinar presented by Ana Morfesis titled “Characterizing the zeta potential & Isoelectric Point of Nanomaterials” we got such a good turnout that we were not able to address the numerous questions asked during the event.
Thank you for the participation!
Since there was such strong interest, we have provided the following list of questions and answers to benefit all who are interested.  We have also provided a table of common metal oxide IEPs, as shown to the left.
 
 
For those who were not able to attend the live event, the session was recorded and is …

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Customer experience, Dynamic Light Scattering, Electrophoretic light scattering, Molecular size, Particle size, Zeta potential, Zetasizer »

[25 May 2017 | ]

A challenge to all new Zetasizers!
 
The Zetasizer is so simple to use that the majority of Zetasizer (user)s just “dive in” and find out how to operate the system.
By design it is (almost) indestructable, so what can go wrong? Not much – nevertheless, you might be able to get even more use and benefit from your system with a little preparation.
 
Free eLearning video – really!
If you are relatively new to the Zetasizer then take a look at our free eLearning introductory course. It was meant as a teaser for the …

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Dynamic Light Scattering, Electrophoretic light scattering, Meet the Experts, Static Light Scattering, Zeta potential, Zetasizer »

[16 Mar 2017 | ]

Recently, I hosted a webinar which discussed what surface zeta potential is and how it can be measured. The webinar attracted huge interest and it was a pleasure to see so many people attending and asking some excellent questions. In fact, there were so many questions asked, that we ran out of time at the end of the webinar and had to answer many of them via e-mail. Some of these are listed below.
The webinar discussed the zeta potential of solid, planar surfaces (rather than colloidal dispersions or molecular solutions) …

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Electrophoretic light scattering, Protein Mobility, Tech Talk, Zetasizer »

[12 Jan 2017 | ]

Electrophoretic mobility measurements from proteins: How to protect proteins in an electric field
 
What is the protein mobility mode?
When applying an electric field to a sample containing protein molecules, there are a few considerations to take into account to avoid “over-stressing” delicate biomolecules. The force a charged object experiences in an electric field is proportional to its charge times the electric field. Therefore the electric field strength (defined by the applied voltage divided by the distance between the electrodes, in V/cm) is more relevant than the absolute value of the applied …

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Customer experience, Dynamic Light Scattering, Electrophoretic light scattering, Molecular size, Molecular weight, Particle size, Zeta potential, Zetasizer »

[20 Oct 2016 | ]

How can I save paper and print a Zetasizer report as a PDF?
 
Why print?
The Zetasizer software includes several popular report options. The most frequently used of these is probably the Intensity PSD (M), which gives a compact overview of the results. It lists the z-average and up to three peaks by intensity with their respective mean size, the area under the peak in % intensity and the standard deviation of the peak. In addition, several relevant sample identifiers and measurement conditions, like the sample name,  file name, refractive index of …

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