Any bioanalytical procedure can be broadly divided into three processes: Extraction, Separation and Detection. Whilst extraction methodologies (SPE, LLE/SLE or protein precipitation) have the primary purpose of eliminating the bulk of endogenous material; and detection (Radiochemical, Optical or more commonly MS) helps define the assay specificity, separation techniques such as UPLC™/HPLC, GC or CE, are key to ensuring a high degree of assay selectivity.
LC-MS/MS has long been the gold standard for small molecule bioanalysis, however, increasing needs for assessing broader chemical space, quantification of new modalities or simply improving assay sensitivity and/or robustness have all led to the requirement for more complex analytical solutions.
Although multi-stage extractions have been successfully employed to solve certain analytical challenges (such as patient-specific matrix effects in clinical studies or complex therapeutic agents), these types of methodologies can be time consuming and challenging to automate. An alternative approach involves the development of multi-dimensional separations which provide increased assay performance through either simplified sample treatment (which is easier to automate), or higher levels of chromatographic/electrophoretic separation (which improves the assay selectivity). In a recent e-Book on Advanced LC-MS Application in Bioanalysis (published by Future Science), Dr Graeme Clark, Head of Analytical at Cyprotex, has authored a chapter dedicated to Multi-dimensional Separations and its applicability in the modern bioanalytical laboratory. Whilst still considered by some to be a black-art, due mainly to its relatively complex plumbing requirements, multi-dimensional approaches, and 2D LC-MS/MS in particular, are growing in application. This rise in popularity is due in no small part to vendors, such as Waters, Agilent and ABSciex producing commercially available modules that simplify the set-up of what otherwise would be a daunting fluidics system.
So whether, you’re simply looking to increase sensitivity with a simple large volume ‘trap and elute’, or interested in increasing your analytical robustness through orthogonal, heart-cut separations, it is becoming more and more apparent that multi-dimensional separations offers numerous solutions to numerous problems – without a part-time interest in plumbing!
To learn more about Cyprotex’s multidimensional separation techniques, contact email@example.com