Created with MindGenius Business 2005Created with MindGenius Business 2005®®

Advanced Techniques Advanced Techniques

Immunoaffinity techniquesImmunoaffinity techniques Tandem techniquesTandem techniques

Created with MindGenius Business 2005Created with MindGenius Business 2005®®

Advanced Techniques (1) Advanced Techniques (1) Immunoaffinity chromatographyImmunoaffinity 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 2005Created with MindGenius Business 2005®®

Advanced Techniques (2)Advanced Techniques (2)Tandem techniquesTandem techniques LC-MS & GC-MS: Allows separation of species by LC-MS & GC-MS: Allows separation of species by chromatography, followed by MS of resultant ionschromatography, followed by MS of resultant ions MS/MS: Three main techniquesMS/MS: Three main techniques

Product ion scan: Single ion selected and Product ion scan: Single ion selected and refragmentedrefragmented

Precursor ion scan: Precursor ions which result in an Precursor ion scan: Precursor ions which result in an ion of interest identifiedion of interest identified

Neutral loss scan: identifies ions that lose a Neutral loss scan: identifies ions that lose a particular fragmentparticular fragment

Tandem techniques represent the gold standard for Tandem techniques represent the gold standard for most pharmacological, biomedical and environmental most pharmacological, biomedical and environmental analyses today.analyses today. http://www.speciation.net/md/000/001/878/http://www.speciation.net/md/000/001/878/

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