X'Press 2/2015

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X'Press 2/2015

Our periodical X'Press, the customers' voice, contains news items, reports of trips and conferences and customer stories.

A productive synergy between X-rays and neutrons

For a long time researchers in the Disordered Materials group at ISIS, the neutron facility at the Rutherford Appleton Laboratory (RAL) in the UK, have studied scattering from non-crystalline materials, specifically liquids and glasses. Prof. Alan Soper FRS, is a world expert on the structure of water and has studied structural transformations in amorphous ice and supercooled water. The understanding gained from these studies has relevance in many fields, for example in human biology where investigating water’s structure can reveal the transfer of ions around the body’s cells and how water clusters around proteins. In astrophysics, measuring the water-ice phase diagram aids the interpretation of spectral data from distant galaxies.

In Alan’s work, instead of looking at the Bragg peaks in a diffraction pattern, as one would for a crystalline material, he studies the diffuse scattering using the ‘total scattering’ or pair distribution function analysis (PDF) technique. The diffuse scattering contains information about the atom-atom correlations in the liquid or glass and enables a model to be built detailing the preferred atomic interactions within that material. Having used this methodology with neutrons, Alan was keen to combine the neutron scattering data with data from X-ray scattering. He was interested in having a dedicated X-ray source close to his neutron scattering experiments.

Alan was PANalytical’s first customer to install an X’Pert³ diffractometer using a silver (Ag) tube for PDF studies. Situated in a dedicated X-ray lab in the same building as the neutron beam lines, the X-ray diffractometer is conveniently at hand for users to easily transfer samples between instruments. Users from all over the world come to use ISIS; as part of their awarded beam time at ISIS they have the opportunity to also collect X-ray data on their sample using the XPert³ diffractometer.

The Disordered Materials group at ISIS generally use the X-ray diffractometer in transmission mode with the sample contained in a quartz capillary. The data is processed by software written by Alan, and provides the interference function in reciprocal space, together with the radial distribution function. Subsequent incorporation into a combined neutron and X-ray modelling method allows the determination of the preferred interactions, atomic arrangements and molecular conformations in glasses and liquids. This approach can be applied to seemingly simple systems such as water, although the structure of water in both its solid and liquid forms still continues to produce surprises [1].

Other fundamental studies of solvents benefit from using both X-ray and neutron diffraction, for example the investigation of the stacking of molecules in liquid chloroform [2]. More complex liquid systems can also be investigated, such as the conformation and hydration of the neurotransmitter dopamine in aqueous solution. This provides further understanding of the interaction of the chemical in the body [3].

But the technique is not limited to liquid systems. The combination of X-ray and neutron measurements has proved highly beneficial for determining the local structure in glasses. Measurements made at ISIS have shed light on the structure directed divergence in physical properties of iron phosphate-based glasses, which are promising radioactive and toxic waste immobilization materials [4].

[1] A.K. Soper, ISRN Physical Chemistry 2013 (2013) 1-67
[2] J.J. Shephard, A.K. Soper, S.K. Callear, S. Imberti, J.S.O Evans, C. Salzmann Chem Commun.,
51 (2014) 4770-4773
[3] S. K. Callear, A. Johnston, S.E. McLain, S. Imberti, J. Chem. Phys 142 (2015) 014502
[4] P.A. Bingham, E.R. Barney J. Phys.-Condens. Mat. 24 (2012) 175403

It’s a great credit that PANalytical can make this machine so reproducible and requiring so little maintenance. Prof. Alan Soper, STFC Senior Fellow and member of the Disordered Materials group at ISIS

About Alan and NIMROD

Prof. Alan Soper FRS is a world leading experimentalist on the structure of water and aqueous solutions. He is a Senior Fellow of the UK’s Science and Technology Facilities Council (STFC) and is a Fellow of The Royal Society (FRS). He is also the designer of NIMROD, the near and intermediate order neutron diffractometer, at the ISIS neutron spallation source, situated at the Rutherford Appleton Laboratory, UK.

NIMROD is the only diffractometer of its kind in the world as it bridges the gap between small-angle neutron scattering (SANS) and wide-angle neutron scattering, by using short and long wavelength neutrons together with a high detector coverage to encompass a wide range of Q space. This enables continuous access to length scales ranging from the interatomic (<1 Å) through to the mesoscopic (>300 Å). The Disordered Materials group at ISIS also operate two other neutron diffractometers, GEM and SANDALS, and generate novel computational techniques for interpreting diffraction data.

XRD applications now and in the future

Martijn Fransen, product marketing manager X-ray diffraction, about ‘How to advance’

During the last years advances in data analysis software and X-ray
detection have changed the world of X-ray diffraction considerably.
Martijn Fransen, product marketing manager X-ray diffraction

Download X'Press 2/2015 at the bottom of this page to read the full article.

Epsilon 1 Pharma – Advanced quantification of catalyst residues in pharmaceutical materials

The Annual Meeting of the American Association of Pharmaceutical Scientists (AAPS) in November 2014 served as stage for the launch of PANalytical’s new Epsilon 1 Pharma. The instrument comes pre-calibrated for quantifying catalyst residues (Ru, Rh, Pd, Ir, Pt) and is tailored for the pharmaceutical industry including 21 CFR Part 11 software together with Installation Qualification (IQ) and Operation Qualification (OQ) documentation. The Epsilon 1 Pharma release coincides with changes in the United States Pharmacopeia (USP) and International Conference on Harmonization (ICH) requirements for elemental impurity analysis.

A key source of impurities in pharmaceutical products are catalysts used in their production process. As these may be harmful to users, regulatory guidelines have been developed which define reproducible and precise monitoring methods. Chapter <231> of the United States Pharmacopeia had been in use since 1905 as the industry standard for the control of elemental impurities. However, this approach lacks both selectivity and sensitivity, and can fail to detect key elements at toxicologically relevant levels.

Since 2005, the USP has been working to develop new regulations. A process of consultation with the industry, chemists and toxicologists has produced two recently published chapters: USP <232> (changes to the concentration limits for elemental impurities ) and USP <233> (changes to the testing methods). These requirements will affect products newly released onto the market as well as legacy products, which will need to be retested for compliance.

USP <233> allows manufacturers a choice in the analytical method used for the determination of elemental impurities, providing two example procedures based on ICP (inductively coupled plasma) methods. These techniques are already in use in parts of the industry. As there is dilution required during sample preparation errors in analysis cannot be excluded, while the cost of the instruments may be prohibitively expensive.

Alternative methods for elemental impurity testing are permitted, where the technique has been validated in line with the requirements in USP <233>. X-ray fluorescence (XRF) is one of the new options and has recently been added to the USP as chapter <735> X-ray fluorescence spectrometry. XRF is well-established in other industries and may be used for both product development and process control. It follows similar principles to X-ray diffraction, which is widely used in the pharmaceutical industry for many applications, including studying polymorphism.

Although it is not yet established in the pharmaceutical sector, XRF offers several significant advantages over ICP:
– XRF is non-destructive, which is important during drug development
when samples may be in short supply.
– XRF involves minimal sample preparation, avoiding the dilution errors which can occur with ICPbased methods.
– No solvents are needed, reducing the cost of ownership.
Epsilon 1 Pharma is the latest in PANalytical’s range of Epsilon 1 systems
dedicated to key applications, including mining, lubrication oils, sulfur in fuels, research and education and milk powder - as already presented in previous issues of X’Press (issues 4/2013 and 1/2014).

The Epsilon 1 Pharma is a push-button solution enabling non-expert users to utilize XRF to quantify catalyst residues at concentration levels required by USP <232> and ICH Q3D. Lieven Kempenaers, product marketing manager XRF

PharmaCAT setup samples

The PharmaCAT setup samples are the latest addition to our range of application solutions. They are designed to allow pharmaceutical companies to quantify catalyst residues for catalysts commonly used in the production of pharmaceuticals. Catalyst residues which can be quantified at pharmaceutically relevant levels include ruthenium (Ru), rhodium (Rh), palladium (Pd), iridium (Ir), and platinum (Pt).

Supporting compliance for the pharmaceutical industry

Installation Qualification (IQ) and Operational Qualification (OQ) are verification and validation procedures which cover the whole PANalytical system including the instrument and the software. IQ and OQ are available for customers that are required to meet good laboratory practice (GLP), and good manufacturing practice (GMP) regulations, for example pharmaceutical
and food manufacturers.

In addition to the IQ and OQ procedures we also offer enhanced data security features in our software to support customers abiding by the FDA 21 CFR Part 11 regulation. The FDA 21 CFR Part 11 regulation concerns electronic records and electronic signatures and requires full data traceability to ensure complete analytical integrity. PANalytical’s enhanced data security software tracks authorized and unauthorized attempts for application login/logoff, starting and stopping of instrument
sessions and any changes to electronic records.

The IQ and OQ documentation, and enhanced data security features are included in
the Epsilon 1 Pharma package and are also available as optional extras on all PANalytical systems.

Reliable automated quality check at Teijin Aramid

The production process of aramids consists of three steps, starting with the polymerization of the monomers into a firm fine-grained polymer powder. This polymer is then dissolved in sulfuric acid and spun into fine filament yarn, which is subsequently crimped and treated with a finishing agent. As each of Teijin Aramid’s products has to meet special requirements of the customers, strict
monitoring of the product quality is necessary. Teijin Aramid’s lab in Delfzijl checks all products for elemental impurities which could influence the properties of the produced fibers.

One indicator for the product quality is its color. Teijin Aramid had already used a specialized color-checking camera for a while. They wanted this to be combined efficiently with an X-ray fluorescence (XRF) system for elemental analysis. PANalytical was able to design a very compact automated solution consisting of a Herzog sample press and an industrial XRF analyzer. The colorchecking camera has been included in this automated setup and a 30-position sample carousel allows the automated analysis of a whole batch of samples.

The sample is pressed and then transported on a specially adapted conveyor belt. It incorporates a small platform which can lift the sample towards the color-checking camera. After this initial check the sample is forwarded to the CubiX XRF analyzer for elemental analysis. The SamTracs system takes care of the entire sample tracking and control including the camera. This small but effective automated system has reliably been taking care of Teijin Aramid’s analytical needs for years now on a daily basis.

About Teijin

Teijin Aramid, a subsidiary of the Teijin Group, is a global leader in aramids and is well-known for its four high-performance aramid fibers, Twaron®, Sulfron®, Teijinconex® and Technora®. Delfzijl is one of the company’s three locations in the Netherlands and employs about 250 people. The Japanese mother company Teijin Ltd operates worldwide in more than 150 companies and employs more than 15,000 people.

We are very satisfied with the reliability of this system, which was designed in close cooperation with us. It’s great how the PANalytical people took all our needs and requirements into account. Ing. Armant Reitsema, Method Development at Teijin Aramid