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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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3D structure / imaging, Borate fusion, Claisse, Tech Talk, X-Ray Fluorescence (XRF) »

[8 Feb 2018 | ]

When performed correctly, fusion is the sample preparation technique that leads to the obtention of the most precise and accurate XRF and ICP analytical results. Among all factors that need to be considered to get great glass disks or solutions and therefore excellent analysis, the choice of flux is one of the most important.
Let’s discover why.
An Indispensable Chemical
The flux forms the matrix of the disk analyzed by the spectrometer. It must melt before the sample dissolves into it. An adequate flux allows to:

Optimize the solubility of the sample and …

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Dynamic Light Scattering, Gel permeation chromatography, Kinexus, Laser Diffraction, Malvern Panalytical Events, Meet the Experts, Molecular weight, Nanoparticle Tracking Analysis, Nanosight, OMNISEC, Particle concentration, Particle size, Rheology, Rheometry, Tech Talk, Viscotek, Zeta potential, Zetasizer »

[30 Jan 2018 | ]

We will be attending Pittcon 2018 in Orlando, Florida Feb 26th – Mar 1st and once again we are pleased to feature a number of our recognized characterization experts who will be presenting a variety of short courses throughout the week.
Time is running out, so don’t miss out on the early bird deadline for discounted admission which ends on February 5th.
Below is a listing of our available short course offerings.
We look forward to seeing you in Orlando at one of our short courses and our Booths #2118 & #2119.
Monday, February 26th
Fundamentals of Particle …

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Malvern Panalytical Events, Tech Talk »

[18 Jan 2018 | ]

Top Content
Once again, we have prepared our latest top content materials from beginner’s guides to advanced education.
Malvern Panalytical’s content is available in a variety of formats; to help explain what these different formats are, we have compiled a quick guide of key types below, together with links to our most popular content in 2017:
Application Notes
Application notes describe a customer issue/problem and how it can be resolved with the appropriate Malvern Panalytical solution.

Basic principles of particle size analysis
Measuring the particle size of small sample volumes using laser diffraction
Accuracy and reproducibility in …

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Dynamic Light Scattering, Kinexus, Laser Diffraction, Mastersizer, Nanoparticle Tracking Analysis, Nanosight, Rheometry, Size Exclusion Chromatography, Tech Talk, X-Ray Diffraction (XRD), Zetasizer »

[5 Dec 2017 | ]

It was my great pleasure to present as part of the Worcestershire Innovation Network at their WINN Wednesday event on the 22nd of November, showcasing the best in innovation across Worcestershire.
This included a local company which makes artificial kneecaps and hips, an insight into the building of genomics studies of patients with rare diseases and cancers, an update on the appeal to get a state-of-the-art surgical robot for removal of prostate tumors (reducing discomfort, scarring and hospital stay post-operation). Jess Antley, head of WINN, also gave an update on a new shared space/collaboration …

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Nanoparticle Tracking Analysis, Nanosight, Particle concentration, Tech Talk »

[23 Nov 2017 | ]

Results of a multi-round interlaboratory comparison (ILC) of NanoSight instruments were recently published1, setting a benchmark for repeatability and reproducibility for the Nanoparticle Tracking Analysis (NTA) technique. The limits of measurement were shown to extend beyond the 30 nm –600 nm range (with all NanoSight models), with percentage coefficients of variation (% CV), calculated as sub 5% for monodisperse samples. The process further highlighted how much variability or error might be introduced if inappropriate instrument settings or analytical procedures are used.
As a relatively new technique, there remained questions about the …

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Differential Scanning Calorimetry, Dynamic Light Scattering, MicroCal, Molecular size, Molecular structure, Particle size, Protein Aggregation, Tech Talk, Zetasizer »

[16 Nov 2017 | ]

Measuring aggregation temperature using the Zetasizer

In dynamic light scattering (DLS), the hydrodynamic size and size distribution of particles in solution can be obtained.  It may be of interest to examine this measurement as a function of time and temperature, or as a ‘trend’, as it is called in the Malvern Zetasizer software.  For biological protein samples, this temperature trend is particularly interesting: although at low temperatures a protein may be stable and show repeatable size (and scattering intensity) measurements, typically at some elevated temperature (Tagg), protein molecules will show a tendency …

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ASD, Ground truthing, Near-InfraRed spectroscopy (NIR), Remote sensing, Tech Talk »

[14 Nov 2017 | ]

This November, the ASD webinar focuses on hyperspectral imaging, near infrared spectroscopy (NIRS), and multivariate calibration models (i.e. chemometrics), featuring ASD’s FieldSpec® 4 Hi-Res NG Spectroradiometer.

In this webinar, you will learn:

How the combination of hyperspectral imaging, near-infrared spectroscopy (NIRS), and multivariate calibration algorithms (i.e. chemometrics), enables quantitative mapping of properties of the Earth’s surface
The data that ground-based reflectance measurements of materials can provide for remote sensing applications
How to apply quantitative chemometric calibrations to hyperspectral image data
Examples of successful applications

November’s ASD webinar speaker is Dr. Brian Curtiss; Brian is one of …

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ASD, Tech Talk »

[17 Oct 2017 | ]

ASD has long been the gold standard in field spectroradiometers. ASD pioneered the science of field spectroscopy over 25 years ago and continues to lead the industry with the world’s most trusted field-portable UV/Vis/NIR/SWIR spectroradiometers covering the full solar reflected spectrum.
ASD’s spectroradiometers and spectrometers are portable and deliver fast and accurate spectral measurements. These spectral measurements act as fingerprints, providing important data that leads to solutions in a variety of applications, such as:

Atmospheric research
Forestry, ecology and plant physiology studies
Light energy measurements
Spectroradiometric calibrations
Ingredient testing for dietary supplements and natural products
Lipid, protein …

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Dynamic Light Scattering, Particle size, Tech Talk, Zetasizer »

[26 Sep 2017 | ]

Is there a maximum viscosity for DLS measurements?
The Malvern Zetasizer can determine particle size by dynamic light scattering (DLS). In this technique, the intensity fluctuations are analyzed to find the corresponding diffusion coefficient that led to the fluctuations. The translational diffusion coefficient Dt of a particle is inversely related to its size and the viscosity of the dispersant (or more accurately the hydrodynamic radius rH and viscosity η).

This relationship can be used to predict detectability limits of the technique in general, and this is how we explore the idea of …

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Archimedes, Binding affinity and Kd, Chemical identification, Differential Scanning Calorimetry, Dynamic Light Scattering, Gel permeation chromatography, Image Analysis, Label-free analysis, MicroCal, Microcalorimetry, Morphologi, Nanoparticle Tracking Analysis, Nanosight, Particle concentration, Particle shape, Particle size, Protein Aggregation, Raman spectroscopy, Resonant mass measurement, Rheology, Size Exclusion Chromatography, Taylor Dispersion Analysis, Tech Talk, Viscosizer TD, Viscotek, Zetasizer »

[21 Sep 2017 | ]

I know this sounds like the beginning of a bad joke, but in this case, it was actually the beginning of the 2017 Colorado Protein Stability Conference, held in July at Beaver Run Resort in Breckenridge, Colorado. In attendance was a range of scientists and researchers from all over the world, with one common subject in mind: Protein Stability.

One of the highlights of this conference was the pre-conference workshop. This was a free workshop for all attendees of the conference, which was sponsored by Malvern Panalytical. The workshop included a range …

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Binding affinity and Kd, Isothermal Titration Calorimetry, MicroCal, Tech Talk »

[12 Sep 2017 | ]

Binding Affinity
Understanding binding affinity is key to appreciation of the intermolecular interactions driving biological processes, structural biology, and structure-function relationships. It is also measured as part of the drug discovery process to help design drugs that bind their targets selectively and specifically.
We recently launched a new short video showcasing the MicroCal PEAQ-ITC and how it is an essential piece to any biological interaction analysis toolkit for measuring Binding affinity and stoichiometry.

The MicroCal PEAQ-ITC offers key benefits over other ITC systems including:
PEAQ-Expert: New easy-to-use software to guide your way includes built-in …

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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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Morphologi, Particle shape, Raman spectroscopy, Tech Talk »

[31 Aug 2017 | ]

GEN covers the role of MDRS in reducing the need for clinical bioequivalence endpoint studies
Raman spectroscopy and MDRS enable determination of the size and shape of specific components within a multi-component blend.
This article followed the recent approval of an abbreviated new drug application (ANDA) for a locally-acting mometasone furoate nasal spray, which provided the opportunity for the US Food and Drug Administration (FDA) to highlight the pivotal and pioneering role MDRS played.
MDRS enables determination of the size and shape of specific components within a multi-component blend. For the purposes of …

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Laser Diffraction, Mastersizer, Particle size, Tech Talk »

[1 Aug 2017 | ]

Just when I thought I’d seen everything that could contaminate the background, a user sent me this picture! The Musca Domestica (common housefly) was attracted by certain aromatics used in testing and seems to have entered the measurement cell through an empty Hydro EV over a weekend. Unfortunately, it became wedged within the measurement cell and did not survive the experience.

The most important message from the Mastersizer training courses I give is to make sure you have a good background before you start. Laser diffraction is a background subtracted technique: …

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Dynamic Light Scattering, Tech Talk, Zetasizer »

[11 Jul 2017 | ]

A webinar entitled “DLS in 30 Minutes” was given in June which attracted a very large audience. The presentation introduced dynamic light scattering and covered the principles of the technique, a discussion of how the measurement is performed, how the data is analyzed and how the results obtained should be interpreted.
We were inundated with various questions during the webinar and we only had time to answer a few on the day. The remainder of questions were answered via e-mail but we thought it would be good to share some of …

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Laser Diffraction, Mastersizer, Meet the Experts, Particle size, Tech Talk »

[13 Jun 2017 | ]

I recently presented a webinar exploring the practical aspects of sieving method – the advantages and disadvantages.  I compared the method to other techniques such as laser diffraction indicating the increased wealth of information that can be obtained with these more modern instrumental techniques and the common pitfalls and assumptions of the screening technique.
More than 800 of you registered for the webinar and I received a large numbers of interesting questions which I have been working steadily through. I thought it would be a good idea to share the questions and answers via the blog, so here they …

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Kinexus, Rheology, Tech Talk »

[8 Jun 2017 | ]

How to best measure a viscosity flow curve?
Choosing the right measuring geometry and preventing measurement artifacts
There are several ways to obtain viscosities at different shear rates using a rotational rheometer. For instance, we could gently ramp through the different speeds starting at the lowest and ending at the highest (good for a quick measurement where time is of the essence).  Alternatively, we could step through the required shear rates as discussed later, while waiting for a steady state viscosity at each step.  This is known as generating an equilibrium flow …

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Meet the Experts, Particle size, Tech Talk »

[30 May 2017 | ]

On April 26th, 2017, I had the great pleasure of being invited to talk as part of the very first Malvern TEDx evening, held at the Coachhouse Theatre in Great Malvern.  It was a really enjoyable event, and the talks are now on YouTube for you all to view!

I gave a top-level overview of how so many of the products and devices we consume or encounter on a daily basis are specifically designed by chemists and other scientists, so that they work the way we need or want them to. From …

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Differential Scanning Calorimetry, Isothermal Titration Calorimetry, MicroCal, Microcalorimetry, Molecular weight, Tech Talk »

[23 May 2017 | ]

A professional and personal view
If your newsfeed from scientific and mainstream media sources is anything like mine, you have seen numerous articles and blogs about the ‘reproducibility crisis’ in the life sciences.
Well-established cornerstones of scientific inquiry and research are the publication of findings in peer-reviewed journals, along with the opportunity for others to reproduce and verify published data.  This advancement and consolidation of knowledge leads to further understanding on how biological systems work, and provides the basis for the discovery and development of new drugs which benefit all of us.
However, there …

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