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Tech Talk

Binding affinity and Kd, Differential Scanning Calorimetry, MicroCal, Tech Talk »

[11 Sep 2018 | ]

This blog answers FAQs on the new Automated and Manual MicroCal PEAQ-DSC systems. For more information, check your user manual, or contact your regional Malvern Panalytical Support.
 
 
 
Q: How much sample do I need to fill the MicroCal PEAQ-DSC cell?
For the MicroCal Automated PEAQ-DSC, you need to have at least 325 μL of the sample or buffer in the appropriate well of the 96-well plate. This is the default setting for the experimental setup. 300 μL is removed by the filling syringe.
You can use a larger sample volume (up to 400 μL)  and …

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Borate fusion, Claisse, Tech Talk, X-Ray Fluorescence (XRF) »

[6 Sep 2018 | ]

Platinumware is used in sample preparation by fusion for XRF and ICP analysis. Crucibles (used for XRF and ICP analysis) and molds (only used for XRF) are made of 95% Pt and 5% Au.
Why use platinum and gold?
It has been proven that this alloy has a high melting point and can withstand extreme heat. Platinum has a great thermal conductivity and ensures very low contamination of the molten mixture during fusion. The addition of gold has a non-wetting effect. In short, the alloy of these two precious metals allows the …

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Crystal Structure Determination, Empyrean, Phase identification, Phase quantification, Tech Talk, X'Pert³, X-Ray Diffraction (XRD) »

[4 Sep 2018 | ]

Since I made my first steps in the powder diffraction community, I have been amazed by the many possibilities for collecting diffractograms. In this blog, I’ll describe how I learned about the advantages of transmission geometry over reflection geometry for specific samples.
In almost every powder diffractometer, the reflection geometry is being used: the detector is at the same side of the sample surface.
This geometry works very well for inorganic materials that can be prepared as flat samples with randomly oriented crystallites.
One of the disadvantages of reflection geometry is that it …

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Image Analysis, Morphologi, Tech Talk »

[28 Aug 2018 | ]

How the development of automated test scripts has increased test coverage and improved the overall quality of the software on the Morphologi 4 and 4-ID
My role as the Software Test Engineer of the Morphologi team is to ensure that changes made to the software meet the acceptance criteria and the high-quality standards of the overall software are still met. I find the work we do at Malvern Panalytical fascinating, however, testing software used for applications like Morphologi 4 and 4-ID has its challenges – the biggest of which is the time required to run …

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Gel permeation chromatography, Molecular structure, Molecular weight, OMNISEC, Size Exclusion Chromatography, Tech Talk »

[22 Aug 2018 | ]

The most common detector in any GPC/SEC instrument is a refractive index (RI) detector.  There are multiple reasons for this, but the most important is because the difference in refractive index between that of a sample solution and that of the same solvent without a sample is directly proportional to the concentration of the sample.  This is why RI detectors are referred to as concentration detectors.  (It should be noted that UV-Vis detectors are also concentration detectors, but require the sample has a chromophore and absorbs light at a detectable …

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Differential Scanning Calorimetry, Label-free analysis, MicroCal, Tech Talk »

[14 Aug 2018 | ]

In a previous blog, I discussed best practices to achieve high-quality data with a MicroCal DSC. Here are more best practices for the MicroCal PEAQ-DSC system, as well as the MicroCal VP-Capillary DSC and VP-DSC systems. These best practices apply to the analysis of proteins in solution, and other biopolymers.
 
 
Sample requirements:

For high-quality Differential Scanning Calorimetry (DSC) data, the samples need to be in desired buffer (pH, salt, excipients, etc.), and the matched buffer is used in the DSC reference cell and for buffer-buffer scans.
Prepare samples in the desired buffer …

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Dynamic Light Scattering, Molecular size, Particle concentration, Particle size, Tech Talk, Zeta potential, Zetasizer »

[2 Aug 2018 | ]

 
Thanks to all who attended the launch webinar for Malvern Panalytical’s new Zetasizer systems, and special thanks to Mike Kaszuba for presenting a clear and interesting overview of the two instruments – we hope you all enjoyed it and found it interesting.

The launch of the Zetasizer Pro and Zetasizer Ultra received a great response and naturally, due to the innovations included in the new systems, lots of questions were sent to us both during and after the webinar. We’ve taken the opportunity to answer the most frequently-asked questions here, in …

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Borate fusion, LeDoser12, Tech Talk, X-Ray Fluorescence (XRF) »

[31 Jul 2018 | ]

The weighing step is of major importance in sample preparation by fusion since it has a direct impact on the analytical results.
Let’s see five best practices to ensure repeatability and productivity while weighing.
REPEATABILITY
Find the right weighing method
There are three weighing methods in sample preparation: sample-to-flux ratio, catch weight and manual weighing. The far best choice is sample-to-flux ratio since it ensures great repeatability and can be performed automatically using LeDoser-12 instrument. With this method, no software correction is required.
Avoid transferring the weighed content into a different container
You should always weigh …

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Gel permeation chromatography, Molecular weight, OMNISEC, Size Exclusion Chromatography, Tech Talk »

[12 Jul 2018 | ]

To many people, obtaining molecular weight information from GPC/SEC analysis involves a lengthy calibration process.  A series of standards of known molecular weight are analyzed and a calibration curve based on the standards’ retention volume is generated.  This can be a tedious procedure, and the result is only relative molecular weight data.
The inclusion of a light scattering detector in a GPC/SEC system eliminates the need to run a series of standards to generate a calibration curve, as the sample’s molecular weight is measured directly by the light scattering detector.  This …

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Dynamic Light Scattering, Tech Talk, Zeta potential, Zetasizer »

[10 Jul 2018 | ]

Dynamic light scattering (DLS) is widely used for ensemble characterization of hydrodynamic particle size, but I have a number of frustrations with the technique.
We measure our valuable samples in low concentrations and in very small volumes, so we use expensive, low volume, glass cells, which are optically superior to disposable plastic cuvettes, but we spend far too much time cleaning them, significantly reducing the productivity of our group.
Also, our samples range from monodisperse proteins to polymeric nanoparticles to liposomes, ranging from the nano-scale into the micro-scale and we need to …

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

[28 Jun 2018 | ]

What causes the most headaches for a particle characterization scientist?
There are many answers to this question, but one of the most obvious is dust or contaminants! As someone who regularly uses Dynamic Light Scattering (DLS) to measure particle size, the possibility of there being dust or contaminants in my sample is one of the things I always bear in mind.
The way I prepare my sample, the way I store my sample before measurement, remembering to put the measurement cap on the cuvette, but only after I’ve cleaned it using an …

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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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Crystal Structure Determination, Empyrean, Phase identification, Phase quantification, Tech Talk, X-Ray Diffraction (XRD), X-Ray Scattering »

[24 May 2018 | ]

Detection of trace polymorphs, determination of amorphous content, and the study of the stability of active pharmaceutical ingredients (APIs) subjected to heat and humidity are some of the many applications where a modern powder X-ray diffraction (PXRD) system can add value to drug development.  Advances in beam conditioning and detector technology have led to greatly improved detection limits, resolution, and range of applications now possible. Today’s modern, laboratory-based PXRD instrumentation and advanced software can greatly assist pharmaceutical scientists in their quest to develop high quality, stable products and accelerate their …

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Elemental analysis, Elemental quantification, Epsilon, Tech Talk, X-Ray Fluorescence (XRF) »

[17 May 2018 | ]

Outdoor air pollution can have many sources, both anthropogenic (power generation, vehicle emissions, industrial and agricultural emissions, etc.) and natural, for instance, volcanic eruption, wind erosion or wildfires.  A key area of concern is the Suspended Particulate Matter (SPM), which can have adverse effects on health, particularly in the particle size ranges under ten microns.  These are further characterized by two designations – PM10 (2.5 – 10 micron) and PM2.5 (<2.5 micron), with PM10 having the ability to penetrate deep into lungs, and PM2.5 able to permeate throughout the body …

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Customer experience, Dynamic Light Scattering, Molecular size, Particle size, Tech Talk, Zetasizer »

[15 May 2018 | ]

The peaks in your distribution are out of order?
We recently received an email about the order of peaks in the Zetasizer software:
For data evaluation, is it possible to rearrange the NNLS results by order of particle size populations?”
How the peaks are shown (by area)

Size measurement results are typically viewed in the Intensity PSD (M) tab. This is part of the standard Size and Summary workspaces.  When a record contains more than one peak, these results will be tabulated in the table above the intensity size distribution. The default ordering in …

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Insitec, Laser Diffraction, Mastersizer, Particle size, Tech Talk »

[17 Apr 2018 | ]

What is IIoT?
We now live in a world where there is an increasing reliance on the internet, not only for streaming movies or sending e-mails but for controlling a multitude of devices from domestic appliances to smart cars. The internet of things has also been embraced by the manufacturing industry, a paradigm known as the IIoT (Industrial Internet of Things) – when separate manufacturing units begin to function as one – and where the cloud is becoming the preferred way to store and share data.
Data has now become the lifeblood …

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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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