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Protein Aggregation

Characterization of sub-visible protein aggregates in biotherapeutic formulations.

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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Binding affinity and Kd, Differential Scanning Calorimetry, Dynamic Light Scattering, Gel permeation chromatography, Isothermal Titration Calorimetry, Label-free analysis, Malvern Panalytical Events, Meet the Experts, MicroCal, Microcalorimetry, Molecular size, OMNISEC, Protein Aggregation, Size Exclusion Chromatography, Taylor Dispersion Analysis, Viscosizer TD, Viscotek, Zetasizer »

[13 Jun 2018 | ]

The time is fast arriving for the third in our highly successful series of European MicroCal meetings! This year the meeting is organized by Malvern Panalytical alongside a Scientific Committee of expert users from academia and industry, all with the support of the ARBRE-MOBIEU network. Our venue will be the prestigious Institute of Engineering and Technology (IET), within the historical Savoy Place, perched on the north bank of the River Thames, with spectacular views across London.
The event will focus on applications, best practice, advanced data analysis and all the latest developments in both isothermal …

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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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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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Differential Scanning Calorimetry, Dynamic Light Scattering, Meet the Experts, MicroCal, Molecular size, Molecular weight, OMNISEC, Particle concentration, Protein Aggregation, Size Exclusion Chromatography, Taylor Dispersion Analysis, Zetasizer »

[18 Jul 2017 | ]

Monoclonal Antibodies – or mAbs for short

Since many of these mAbs require refrigeration we had used dynamic light scattering (with a Zetasizer) to show the formation of aggregates after freeze-thaw cycles (for details see application note “Effect of storage conditions on Immunoglobulin“). These could be seen both in the increased polydispersity index (PDI) and the appearance of a large-size aggregate peak in the intensity size distribution as shown to the right. The area under the peak gives an indication of the presence of the large aggregates but is not suited for …

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Archimedes, Customer experience, Differential Scanning Calorimetry, Gel permeation chromatography, Image Analysis, MicroCal, Morphologi, Nanoparticle Tracking Analysis, Nanosight, Particle size, Protein Aggregation, Raman spectroscopy, Resonant mass measurement, Viscotek »

[1 Jun 2017 | ]

Our key driver at Malvern Instruments is to create technologies that make a difference or solve a problem, and working hand-in-hand with our customers enables us to make sure that’s exactly what’s happening, out in the field.  We place a high value on our collaborations and partnerships with customers from a wide range of industries and organizations across the globe and love to see how our systems are being used in real-world scenarios.  This gives us vital feedback on what we’re doing well, and also any tweaks we need to make in order to optimize …

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Archimedes, Chemical identification, Label-free analysis, Malvern Panalytical Events, MicroCal, Microcalorimetry, Molecular size, Molecular structure, Molecular weight, Morphologi, Nanosight, Particle concentration, Particle shape, Particle size, Protein Aggregation, Protein Mobility, Viscosizer TD, Zeta potential, Zetasizer »

[16 May 2017 | ]

With Pre-Conference Workshop on Biophysical Characterization and Particle Analysis
 

Date: July 17th – 20th.
We at Malvern know that protein stability is important in numerous disciplines, ranging from basic and medical biochemistry to pharmaceutical sciences. However, it is rare that researchers from all the relevant areas can join to discuss the critical issues in the field. The 2017 Colorado Protein Stability Conference provides a unique forum for this exchange of information. The topics to be covered include protein folding, dynamics and thermodynamic stability; amyloidosis and protein aggregation; and stability, formulation, analysis and processing …

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Dynamic Light Scattering, Molecular size, Particle concentration, Particle size, Protein Aggregation, Tech Talk, Zetasizer »

[7 Mar 2017 | ]

How can I use DLS for sample xyz?
What sample concentration / refractive index is needed for reliable DLS size measurements?

Has it been done before?
In Dynamic Light Scattering (DLS) intensity fluctuations in the sample are analyzed to obtain size information on the sample. The technique is applicable to a wide size range from sub-nanometer up to a few microns. In order to obtain a meaningful result, a minimum scattering signal strength must be present. Malvern’s Zetasizer Nano software contains a calculator to help estimate the required minimum concentration.
If anyone else has …

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Dynamic Light Scattering, Molecular size, Protein Aggregation, Tech Talk, Zetasizer »

[1 Nov 2016 | ]

α-synuclein promotes vesicle assembly – when size can support theory
 

What is a vesicle?
In cell biology, a vesicle is an (often spherical) assembly of amphiphilic molecules (usually proteins and phospholipids), and is typically sized between 30 nm – 100 nm in diameter. Vesicles are often classified by the type of interaction they are involved with. For extracellular vesicles (or exosomes), this is usually intercellular signal transmission. A particular example of exosomes is synaptic vesicles, which transmit signals between neurons (average size: 40 nm).
In a paper entitled “Structural basis of synaptic vesicle assembly …

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Dynamic Light Scattering, Electrophoretic light scattering, Meet the Experts, Particle size, Protein Aggregation, Zeta potential, Zetasizer »

[11 Oct 2016 | ]

Adjuvants for vaccination – How size and zeta may be relevant
 
What is an adjuvant?

Adjuvants are substances which are added to medicines to trigger and enhance an immune response to an antigen. In the USA, the most commonly-used adjuvant is alum, and many vaccines in use today contain some aluminum components to help the vaccine work better. While the exact mechanisms of how adjuvants work is unclear to some extent, a typical adjuvant component is much larger than the antigen or antibody itself, often around 100 nm in radius.
In a paper …

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Dynamic Light Scattering, Nanoparticle Tracking Analysis, Nanosight, Particle concentration, Particle size, Protein Aggregation, Tech Talk, Zetasizer »

[15 Sep 2016 | ]

Nanoparticle Tracking Analysis or Dynamic Light Scattering ?
After a recent joint NanoSight and Zetasizer demonstration, I received this set of questions that helps illustrate the core of the issue of these two techniques:

Since the Nanosight gives me particle concentration, it’s somewhat straightforward to calculate what % of my Nanoparticles are aggregated. Can I calculate % aggregated particles in the DLS as well?  Or does the varying amount of intensity, and the protein+nanoparticle mixture in the sample confound that calculation?

If I wanted to measure non-spherical particles (for example nanorods), which …

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Nanoparticle Tracking Analysis, Nanosight, Particle concentration, Particle size, Protein Aggregation, Tech Talk »

[26 May 2016 | ]

We recently published our application note, “Adeno-Associated Virus titer and aggregation characterization“, which discusses a new NanoSight method that allows the visualization and therefore analysis of viruses smaller than what was previously possible to measure.  This represents an exciting extension of the Nanoparticle Tracking Analysis (NTA) technique in response to market demand for tools for better characterization of small virus types.
 
Adeno-Associated Virus (AAV) is commonly used in the gene therapy field as a delivery vector. Tools to characterize both the concentration and purity or aggregation of the samples are limited because the primary virus size is …

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Differential Scanning Calorimetry, Electrophoretic light scattering, Isothermal Titration Calorimetry, Label-free analysis, Malvern Panalytical Events, MicroCal, Microcalorimetry, Molecular structure, Protein Aggregation, Raman spectroscopy, Zetasizer »

[12 May 2016 | ]

I had the pleasure of participating in the 5th International Symposium on Higher Order Structure of Protein Therapeutics, also known as HOS2016, sponsored by CASSS. The meeting was at the Renaissance Hotel in Long Beach, California April 11-13, 2016. I was joined by my Malvern colleagues Rajib Ahmed and David Sanborn.
The HOS Symposium is a platform for open discussion of development and optimization of analytical techniques to study HOS of proteins and biopharmaceutical products (including monoclonal antibodies and antibody-drug conjugates), biocomparability, and biosimilars.
Protein higher order structure (HOS) includes the secondary, …

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Dynamic Light Scattering, Molecular size, Molecular weight, Protein Aggregation, Tech Talk, Zetasizer »

[21 Jan 2016 | ]

How do I know the minimum concentration needed for measuring the size of my protein?

We are asked this question all the time when we are demonstrating the Zetasizer.  Happily, if the Zetasizer software is installed (and it can be downloaded for free, by the way) there is a minimum concentration calculator integrated – so it’s simple! The calculator can be accessed from Tools – Calculators – Concentration Utilities – Minimum Concentration Calculator
Let’s look at a few examples to get an idea of some typical values for your samples. The left …

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Gel permeation chromatography, Protein Aggregation, Tech Talk, Viscotek, Zetasizer »

[15 Sep 2015 | ]

How can a quartz cuvette be properly cleaned?
The Zetasizer has a flow cell [ZEN0023] used in conjunction with either the titrator, the NanoSampler, or as a chromatography or field flow fractionation detector. A similar flow cell [ZMV1008] is also in use with the Zetasizer microV when used as a molecular weight detector in conjunction with the OmniSEC software. Advanced cuvettes may also be used in UV-Vis, fluorescence & circular dichroism spectrophotometers, MALLS as well as goniometer systems and other specialized optical detection. If the signal from the quartz cell …

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Dynamic Light Scattering, Molecular size, Protein Aggregation, Tech Talk, Zetasizer »

[30 Jul 2015 | ]

Often, pharmaceutical formulations contain therapeutic proteins at relatively high concentration. Under such conditions, the stability of the protein as well as the formulation overall is of significant concern. Great effort is invested in optimizing stability, and particular attention goes to the choice of buffer components. Various components might form part of the ‘final’ recipe including cosolvents (such as polyethylene glycol (PEG), glycerol, ethanol) to reduce the dielectric constant of the buffer and influence electrostatic interactions, chelating agents (citric acid or citrate salt buffers, ethylene-diamine-tetra-acetic acid (EDTA), tris(hydroxymethyl)aminomethane (TRIS), tartaric acid) and …

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Molecular structure, Molecular weight, Protein Aggregation »

[21 May 2015 | ]

We recently published a new application note on protein characterization using our latest SEC system, OMNISEC, and I wanted to bring your attention to this elegant piece of work that beautifully shows the kind of information you can get from a multi-detector system and, perhaps more importantly, the kind of information you might be missing from a single-detector, UV-based system.The chromatogram below shows a typical chromatogram of a standard protein,    β-amylase:

It looks pretty typical with a monomer and a small amount of aggregates, right? Wrong!
Let’s looks again with a multi-detector …

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

[31 Mar 2015 | ]

Can one calculate a PDI value excluding a small aggregation peak? For example if the main particle species is ~100nm and there is a small contribution (2% by intensity) from a peak at 5 microns, is it possible to recalculate the z-average and the PDI ignoring the 5 micron peak. Alternatively, is it possible to determine a PDI for the smaller species only?
The z-average will be weighted more towards smaller components, because only the initial part of the correlation function is fit. Following the ISO method to determine the …

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Dynamic Light Scattering, Meet the Experts, Nanoparticle Tracking Analysis, Protein Aggregation, Raman spectroscopy, Resonant mass measurement, Size Exclusion Chromatography, Tech Talk »

[24 Feb 2015 | ]

I recently took part in a question and answer session with BioPharm International about techniques for measuring and characterizing protein aggregates. The full discussion can be viewed here, however I thought I would also use this blog post to summarize the main points.
Essentially, there is a pressing need within the biopharmaceutical industry to understand aggregation pathways, and the risk factors that can induce aggregation, right from the start of the drug development process to align manufacturing processes with Quality by Design (QbD) principles. Given the link between protein aggregation and …

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