Structural Confirmation / Elucidation

For the analysis of synthesised intermediates and final compounds MS and NMR can be used to confirm that the correct molecule has been synthesised based on its expected molecular weight and chemical shift / coupling patterns.

Confirmation of product molecular weight is carried out using mass spectrometry by comparing predicted molecular ion isotopic distribution, calculated from the supplied structure or elemental composition, with actual molecular ion isotope distribution.  Accurate mass analysis can also be used to propose an elemental formula.

The one-dimensional 1H, 13C (including DEPT), 19F and 31P NMR techniques as well as the two-dimensional COSY, NOESY/ROESY, HSQC, and HMBC experiments can be utilised in the determination of structure.

These techniques can also be used in the elucidation of unknowns as well as the identification of known impurities, metabolites and solvents.

Identification of Impurities and Metabolites

Identification and characterisation of materials, degradation products, impurities, metabolites and process impurities is initially carried out using mass spectrometry.  If sufficient sample is available, fraction trapping and subsequent NMR and/or IR may be possible to produce more information about each impurity.

  •  We can carry out ultra sensitive qualitative and quantitative analysis of genotoxic impurities.
  • We can perform the characterisation of peptides, drug substance and reference standards.

Identification of Solvents

Due to the possible harmful effects of solvents used in the manufacturing process of active pharmaceutical ingredients they must be kept below certain recommended levels.  GC-(MS), NMR or a combination of these techniques can be used to identify and quantify residual solvents in samples.

Radioactive compounds

The excellent capabilities of our LC-MS instruments enable the determination of isotopic purities of hot and cold labelled compounds in support of our isotope chemistry services.  Our NMR facilities can also be used to acquire data for hot (14C) and cold labelled (2H, 13C, 15N) compounds.


We have a wide range of techniques to solve your quantitation problems accurately over a wide range of concentrations using HPLC, UHPLC, LC-MS/MS, GC-(MS) and NMR.  For example GC, GC-(MS), NMR or a combination of these techniques to identify and quantify residual solvent impurities in your samples.   LC-MS can be used to confirm the identity and quantify ultra low levels of genotoxic impurities or levels of drug in bioanalytical samples.  This instrumentation can also be used to help with your method development and validation needs.

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