Physicochemical Testing & Storage Stability

  • Physicochemical (or physchem) testing is an integral requirement of product registration for agrochemicals and animal health products. Find out how we can help you with characterisation and physicochemical testing studies.
  • Our Services
Physicochemical Testing & Storage Stability

At Fera Science Limited we support our partners through world-class science to navigate complex regulatory frameworks.

Physicochemical (or physchem) testing is an integral requirement of product registration for agrochemicals and animal health products. At Fera we offer a full range of physicochemical testing capabilities to meet all your regulatory requirements. We can work across a wide variety of materials, ranging from pure, stable substances up to complex mixtures and UVCBs as well as reactive matter. Our experts are skilled in a full array of analytical techniques, including LC, LC-MS, GC, GC-MS and ICP-MS and can provide analytical support for both stability testing as well as physchem characterisation.

"Our extensive experience includes both active ingredients and formulated products."

Examples of our analytical equipment include:

  • Velos Pro OrbiTrap (Thermo)
  • Triple Quad Mass Spec (AB SCIEX)
  • Proton-NMR (Bruker)
  • Carbon-NMR (Bruker)
  • Acquity Xevo TQ-S (Waters)
  • 19 Triple Quad Liquid Chromatography Mass Spectrometers  (LCMS)
  • 3 Time of Flight (TOF) LCMS
  • 2 High Resolution TOF LCMS including Orbitrap technology
  • 14 Gas Chromatography Mass Spectrometers  (GCMS)
  • 3 High Resolution GCMS
  • 2 Ion Ratio Mass Spectrometers  
  • 3 Inductively Coupled Plasma Mass Spectrometers  
  • 2 NMR

  • 14C Radiochemistry Apparatus

  • Liquid Scintillation (Perkin Elmer Tri-Carb)
  • Sample Oxidiser (Perkin Elmer 307)
  • HPLC-βRAM (Agilent and LabLogic Model 4)
  • Laura 4 Radio chromatography (LabLogic)
  • TLC Bio-imaging (FUJI-BAS)

Fera has the best people in the right place focussed on delivering the right solution. We continuously invest in our people and support them in delivering the best science to our partners.
Areas of Expertise

Phil Rooney

Phil is a senior environmental fate scientist with 10 years’ experience in the area. He has a background in biochemistry and manages projects within the environmental fate and behaviour sector. 

Meet the scientists

Eleanor Walker

Eleanor is the Environmental Fate and Metabolism Laboratory Manager at Fera. As Laboratory Manager, part of Eleanor’s role is to ensure that the laboratories and procedures performed are GLP compliant.

Chris Sinclair

Chris Sinclair

Chris is an expert in regulatory environmental risk assessment processes, registration requirements and guidance for pharmaceuticals, veterinary medicines and pesticides.

Take a look inside our Physicochemical Labs

Our Services

Our in-house capability to conduct environmental risk assessment studies that encompass all of the experiments needed for a robust data portfolio means that we can support chemical manufacturers in helping them meet the requirements to bring their product to market. Our physicochem capabilities include:

Service Description
Dissociation in water (OECD 112, Dissociation Constants in Water)
This test determines the dissociation constants of a chemical in water. Dissociation is the reversible splitting of a compound into two or more chemical species, which may be ionic. It is an important factor of assessment as it governs the form of the substance and, in turn, determines its behaviour and transport in the environment. Potential effects include the adsorption of the chemical onto soil and sediments, or adsorption into non-target biological cells. 
Partition coefficient (OECD 107 (Shake flask method), OECD 117 (HPLC method) and OECD 123 (Slow-stirring method)  The partition coefficient of a substance characterises the equilibrium distribution of the compound between water and a lipophilic solvent (commonly n-octanol). The partition coefficient between water and n-octanol, POW, can be used to predict how a chemical will interact within an ecosystem, providing a measure of its tendency to move from the aqueous phase into lipids, leading to bioaccumulation. The three methods cover different logarithmic POW ranges: the Shake Flask method covers values between -2 and 4; the HPLC method between 0 and 6; and the Slow-stirring method can determine log POW values up to 8.2. values. Both the Shake Flask and Slow-stirring methods agitate a compound between volumes of n-octanol and water, followed by determination of the distribution between each phase by an appropriate analytical technique, such as high-performance liquid chromatography, gas chromatography, or photometry. The HPLC method can predict the POW of a compound by comparison of its retention time with reference compounds of similar chemical structures with known POW values.  
Water solubility (OECD 105, Water Solubility) The aim of this test is to determine the solubility of a compound in water. The water solubility of a substance is the saturation mass concentration of a substance in water at a given temperature. 
Vapour Pressure (OECD 104, Vapour pressure)
The vapour pressure of a substance can also be described as its tendency to evaporate, or change from a solid or a liquid into a vapour. In general, a substance with a low vapour pressure is less likely to turn into a vapour and get into the air. A knowledge of a chemical’s vapour pressure gives us a better understanding of how it will react in the environment, where it will go after it is applied and how long it might stay in water, on plants and in soil.
Melting points (OECD 102, Melting point) This test is used to determine the temperature or temperature range required to transition a substance from a solid to liquid state — the melting point. The melting point occurs at normal atmospheric pressure and is considerably affected by impurities in the substance. 
UV-Visble Absorption (OECD 101 UV-Vis Absorption Spectra) This test is used to determine the ultraviolet-visible absorption spectrum of a chemical compound and to give indication of the wavelengths at which the compounds may be susceptible to photochemical degradation.  The degradation of the compound will depend on the amount of energy that is absorbed in the specific wavelength regions. However, no measurable absorption does not mean that photodegradation will not have taken place.


The breadth of our technology allows us to integrate technology and informatics establishes us as a centre of diagnostic excellence accelerating the pull through of emerging technologies into real world applications.

Thomson Suite

The Thomson Suite is one of the largest facilities of its kind in the UK. It is a bespoke laboratory running to GLP quality standards that houses 30 state-of-the-art mass spectrometry instruments.

Learn More

Listen to our team

Fera works closely with plant protection, biocide, animal health and chemical manufacturers to help develop effective, sustainable and safe products that enhance output whilst minimising adverse environmental impacts.

We're looking for the most talented and ingenious minds to help us tackle tomorrow's challenges with an innovative approach. Could you provide the answers?


Read more about what we do in Chemical Regulation

We work across:

  • Ecotoxicology
  • Fate & metabolism
  • Livestock metabolism and residue studies
  • Efficacy services
  • Analytical chemistry
  • Consultancy

Original thinking…applied to serve the agro-chem and veterinary medicines industries

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