Created with MindGenius Business 2005® Advanced Techniques Advanced Techniques Immunoaffinity techniques Immunoaffinity techniques Tandem techniques Tandem techniques

Created with MindGenius Business 2005® Advanced Techniques (1) Advanced Techniques (1) Immunoaffinity chromatography Most often for solid-phase or on-line extraction to preconcentrate analyte Involves Immobilisation of specific antibodies (soft gel or rigid support) Sample is passed slowly through the column, to allow specific analyte adsorption Sample is desorbed by manipulating mobile phase (pH, ionic strength, organic solvent, competition) Concentrated eluent subjected to further analysis Advantages: Improves analytical capability via preconcentration Very good specificity and recovery Disadvantages May not be robust/reusable For analytes, need to produce antibodies

Created with MindGenius Business 2005® Advanced Techniques (2) Advanced Techniques (2) Tandem techniques LC-MS & GC-MS: Allows separation of species by chromatography, followed by MS of resultant ions LC-MS & GC-MS: Allows separation of species by chromatography, followed by MS of resultant ions MS/MS: Three main techniques MS/MS: Three main techniques Product ion scan: Single ion selected and refragmented Product ion scan: Single ion selected and refragmented Precursor ion scan: Precursor ions which result in an ion of interest identified Precursor ion scan: Precursor ions which result in an ion of interest identified Neutral loss scan: identifies ions that lose a particular fragment Neutral loss scan: identifies ions that lose a particular fragment Tandem techniques represent the gold standard for most pharmacological, biomedical and environmental analyses today. _microtof-q_instrument.gif