Measurement Science

Throughout the past 50 years, Colworth Science Park has invested heavily in developing its analytical and measurement needs to deliver excellent solutions to its diverse foods businesses. This has produced a multidisciplinary team of dedicated professionals with skills and facilities unsurpassed in the Foods and Home/Personal Care Industries.

Since the pressures to operate more efficiently and to concentrate resources on core activities are greater than ever, our knowledgeable team of measurement professionals could provide the partner you need to find your measurement solution.

Our areas of expertise are briefly summarised below.

Microscopy

A range of state-of-the-art microscopy techniques are routinely applied to a diverse range of measurement challenges covering distance scales from ‘mm’ down to ‘nm’. Microscopes and imaging techniques are continually evolving and we are keeping pace with the latest developments in Electron Microscopy, Light Microscopy and Image Analysis.

Electron Microscopy
At the highest resolution, molecular, network and ultrastrucutral details can be revealed using Transmission Electron Microscopy (TEM), detailed molecular or structural contrast is achieved using electron dense probes such as negative staining, antibody gold labelling or freeze fracture replica production. For specimens showing structural features from nanometres to millimetres Field Emission Cryo Scanning Electron Microscopy (FESEM) is the method of choice for foods, plant and composite materials - even in hydrated or frozen states.

Light Microscopy
In the micron dimension scale Optical Microscopy methods provide the work horse in structure visualisation - these methods are particularly suited to experiments in real time as structures evolve or change with respect to tension/compression, shear, pressure, time and temperature. The pre-eminent structural characterisation tool in this dimension scale is Confocal Laser Scanning Microscopy (CLSM) which is capable of optical sectioning and hence 3D imaging of composite materials with high clarity. By further exploiting fluorescent labelling procedures multi-component visualisation and dynamic structural studies including those in living cellular systems are also possible.

Image Analysis
For almost any experimental microscopy significant further benefits to understanding are gained by quantifying the visual information through image analysis procedures. These methods can be applied to 2 and 3 spatial dimensions, time dependent phenomena or even multi-spectral dimensions.

Facilities

Range of Leica optical microscopes with Linkam specialist stages for dynamic studies; i.e. temperature, pressure, temperature gradient, shear, tensile, ultrasound and cell-incubator stages.
Confocal microscopes – Leica Spectral Scanning Confocal (TCSSP-1), Biorad MRC600 and Yokogawa CSU22 video rate spinning disc confocal.
‘Phantom 5’’ high-speed camera for imaging ultra-fast dynamic processes. Thermal imaging capability -FLIR Thermovision 570.
JEOL 1200Ex Transmission Electron microscope. TEM also fitted with SEM & STEM facility. Oxford INCA X-ray microanalysis system. Full range of TEM cryo-preparation kit.
JEOL JSM 6060 Scanning Electron microscope for ambient SEM.
JEOL JSM 6301 Field Emission Scanning Electron Microscope fitted with cryo stage and cryo preparation capabilities.

Nuclear Magnetic Resonance (NMR)

NMR is a well established spectroscopic technique capable of measuring both the chemical and physical properties of complex samples. The multi-faceted nature of NMR has resulted in many applications covering a diverse range of problems that span the chemical, physical and biological sciences. NMR has consequently been used in many different industries including chemical, oil, pharmaceutical, biotechnology, medical, consumer products and foods.

High Resolution NMR
Spectroscopy is the method of choice for providing detailed structural characterisation of organic molecules in solution and for mixture analysis. With LC-NMR, compounds are separated by HPLC immediately prior to NMR analysis, whereas in DOSY NMR experiments components of a mixture are resolved on the basis of diffusion. High resolution NMR data obtained directly from complex mixtures can provide valuable compositional profiling information, analysis of which can be enhanced using multivariate statistical techniques as in, for example, metabolomics approaches.

Solid State NMR
Provides a non-destructive probe of the chemical structure of crystalline and amorphous materials. It can also be used to discriminate between solid and mobile components in semi-solid samples, the mobile component of which can be further analysed by HR-MAS.

MRI
(NMR Imaging) provides an ideal non-invasive method for investigating the internal structure of materials – particularly optically non-transparent objects. 2D and 3D images can be obtained to generate quantitative maps of, for example, numerous chemical and physical parameters, including local concentrations, chemical distribution, relaxation times, diffusion and flow-velocity. MRI is also ideally suited for the study of dynamic processes (including water transport properties) such as those that occur during, for example, the processing and storage of products.

Time Domain NMR
Low field time domain NMR is well suited for the elucidation of the microstructure and microdynamics of complex materials based upon measurements of relaxation times and diffusion coefficients. Common applications include the determination of moisture content (e.g. during hydration processes), solid/liquid fat ratios in foods, and droplet sizing of emulsions.

Facilities

The NMR laboratory is well equipped for NMR applications; the instrumentation includes:

Bruker Avance(II) 600MHz spectrometer with full multinuclear and gradient spectroscopy capabilities plus SPE-LC NMR and HR-MAS NMR functionalities (installed Jan 2006)
Bruker DSX300 wide-bore spectrometer with MRI, diffusion (high power gradients), solid-state and HR-MAS capability plus a rheo accessory for rheological NMR measurements
Bruker AMX400 multi-nuclear high resolution spectrometer
Resonance Instruments MARAN 10 time domain spectrometer with 3D-imaging capability
Resonance Instruments MARAN 20 Ultra time spectrometer with 1D profiling and diffusion coefficient capability

Raman & Infrared Spectroscopy

Infrared and Raman spectroscopy are complimentary forms of molecular spectroscopy; both are sensitive to the details of molecular structure through the vibrational spectrum of the molecule of interest. It has wide range of applications based on this chemical specificity with a recent advancement being imaging and microscopy methods allowing chemical maps to be produced on the micron length scale. It can be used to look at molecules in all physical states and can (usually) tell them apart. It is also used to look at ‘ordering’ within these states e.g. drug polymorphs, protein secondary structures and lipid ordering.

Infrared spectroscopy is more sensitive and has greater spectral resolution than Raman and is therefore more suitable to trace/contaminant problems or to problems where time resolution of observations is required. Fourier Transform Infrared (FTIR) spectroscopy offers the ultimate in vibrational spectroscopy resolution and sensitivity and hence is key when a contaminant or foreign body identification is required. For surface or deposited materials then Attenuated Total Internal Reflection (ATR) is the method of choice. We also have a range of other attachments to control the sample environment e.g. temperature and pressure.

Confocal Raman Imaging combines the benefits of optical microscopy resolution, the suitability of Raman spectroscopy for hydrated( and non hydrated) environments and the exquisite chemical selectivity of vibrational spectroscopy methods to provide detailed microstructural descriptions of for example plant, biopolymer and composite materials in their respective phase and interface states all in-situ and non-destructively in 2 or 3 spatial dimensions and across the full vibrational spectrum space. State of the art multivariate chemometric methods provide chemical resolution in microstructural images beyond that achieved through classic analyses. This allows separation of spectra from highly complex multicomponent systems – thereby providing quantitative chemical maps of components of the system.

Facilities

BioRad FTS 6000 FTIR spectrometer with UMA 500 infrared microscope with a range of accessories including variable temperature ATR, Diamond anvil cell (pressure studies), flow cells and cold cell.
Kaiser 5000R Confocal Raman spectrometer. A state of the art confocal Raman system that allows fully automated mapping in 3D on the micron length scale.

Separation Science

Molecular characterisation of materials generally requires the isolation of a given molecule or molecular class followed by its identification and quantification. Many molecules of interest from either a nutritional or functional standpoint are relatively easy to measure using conventional chromatographic techniques such as HPLC with UV, diode array or fluorescence detection. However, the detection of molecular species at very low levels and/or in complex matrices requires more sensitive and selective methods. Our facilities and experience cover most forms of chromatography (gas, liquid, ion) in combination with a wide range of different detection methods and extends to capillary electrophoresis, which we routinely apply for the detection of compounds in complex matrices such as foodstuffs, biofluids etc.

Electrochemical Detection is applicable to the analysis of molecules that are readily either oxidised or reduced. Pulse amperometric detection is widely used for the analysis of, for example, sugars in food matrices, whereas more complex analytical problems such as the detection of trace amounts of electroactive molecules (e.g. antioxidants or vitamins) in biological materials are approached by the use of a coulometric array detector.

Mass Spectrometry can deliver, through its unparalleled selectivity and sensitivity, characteristic chemical fingerprints from microscopic amounts of diverse materials to provide structural elucidation of unknown species as well as purity and confirmation of identity. In combination with different chromatographic techniques mass spectrometric detection can be applied to about 90% of all known organic compounds. We routinely use our expertise for the GC-MS analysis of volatile species and flavours in food materials to identify flavour molecules with positive consumer attributes, or conversely to identify off-flavours arising from, for example, food rancidity or lipid oxidation.

Liquid chromatography (LC) with atmospheric pressure ionisation mass spectrometry (API-MS) complements traditional LC detectors as it allows direct coupling of a LC separation to the mass spectrometer. The technique is routinely used for the analysis of compounds that are not amenable to gas chromatography, without derivatisation. Potential applications range from the quantification of small molecules in biomatrices to the characterisation of high molecular weight biomolecules such as proteins.

Capillary Electrophoresis (CE) is an important modern chemical separation technique that we use routinely for protein characterisation, to study protein/ligand affinity and to examine individual proteins within emulsion systems. The technique is equally applicable to small molecules such as preservatives and vitamins. It provides high efficiency and short analysis time, and is low cost and suitable for work on small sample volumes or in complex matrices.

Metals Analysis: Metals are determined in a wide range of matrices by Atomic Absorption Spectroscopy (flame- and graphite furnace-AAS) or Inductively Coupled Plasma Emission Spectroscopy (ICP-AES). We make use of microwave digestion for rapid sample preparation in a closed vessel reducing the change of contamination or loss of volatile elements. Graphite furnace, hydride generation and cold vapour AAS offer particularly good sensitivity down to 0.01 mg/kg or better depending on the element of choice.

Facilities

The instrumentation of the Separation Science laboratory includes:

Agilent 1100 or Shimadzu HPLC systems with UV, diodearray and fluorescence detector
ESA Coularray 5600 system
Dionex DX500 HPLC system offering pulse-amperometric or conductivity detection
Hewlett Packard 3D- CE with diodearray detection
Thermoquest/Finnagan Masslab Voyager GC-MS with Perkin-Elmer Automated Thermal Desorber
Waters ZMD LC-MS
PerkinElmer OPTIMA 3000DV ICP-AES
PerkinElmer AAnalyst 800 AAS for flame and graphite furnace AAS

Genomics

Functional genomics coupled to bioinformatics enables a deeper insight into the molecular mechanisms underlying complex biological events. In order to obtain more data from precious samples the genomics core facility provides an experienced skill set centred in multiplex analysis of samples, covering sequencing, transcriptomics and protein profiling. Integral to these functions are a strong knowledge and network base to help aid experimental design and platform decision making processes, and a strong suite of bioinformatics programs to aid analysis through from spot to biological networks.

DNA sequencing. Using either ABI 3100 or 3700 sequencers gives us the ability to cover both bespoke small scale projects up to higher throughput mid range projects and includes microsatelitte & mutation analysis in addition to standard sequencing.

Transcriptomics. We have experience and capabilities to process arrays from vendors such as Codelink and Agilent and have also undertaken custom array processing. This enables us to provide transcriptomic analysis encompassing application specific focussed arrays up to and including whole genome arrays. High internal quality control measures, automated processing stations and state of the art data extraction procedures ensures that the results obtained combine high sensitivity and reproducibility. We provide a flexible format that enables us to cover all aspects of the array process from sample isolation through to data analysis and more complex bioinformatics, or to provide a more select service for example hybridisation, scanning and data extraction. Gene ontology and pathway based tools provide the option of biological analysis of the data.

Protein Profiling.Quantitative analysis of selected panels of up to 30 proteins based on the proven Luminex technology platform. Analysis can include multiple cytokine panels, MMPs panels and various adiponectin and CVD panels based on commercially available kits. In addition this profiling can be extended with custom prepared bead sets focussed for particular projects but is dependant on availability of antibodies. Furthermore analysis of cell signalling events or ligand binding assays can be undertaken if required.

Facilities

Perkin Elmer 4000XL 3 colour scanner
Agilent G2565BA scanner
Biorobotics TAS microarrayer
Lucidea Hybridisation Station
Advalytix Slidebooster
Agilent hybridisation oven
Qiagen LiquiChip Workstation
ABI 3100 Genetic Analyser
ABI 3700 sequencer

To find out more please contact:

Dr Scott Singleton
Email: scott.singleton@unilever.com
Tel: +44 (0)1234 222796

Unilever Measurement Science Unit
Colworth Science Park
Sharnbrook
Bedford MK44 1LQ

« Back