Liquid chromatography immunoaffinity

The primary sample extract is subsequently subjected to cleanup using several different approaches including conventional liquid-liquid partitioning, solid-phase extraction, liquid chromatography, immunoaffinity chromatography, and supercritical fluid extraction cleanup. In some instances, more than one of these purification procedures can be applied in combination for better results. 

G. S. Rule, A. V. Moi dehai and J. Henion, Determination of carbofuran by on-line immunoaffinity cliromatography with coupled-column liquid chromatography/mass spectrometiy . Aim/. Chem. 66 230-235 (1994). 

E. M. Thurman and C. Batian, Determination of atrazine and atrazine mercapture in drinking water samples and in urine using immunoaffinity SPE with positive ion spray HPLC/MS , Presented at the 15th Symposium on Liquid Chromatography/Mass Spectrometry, Montreux, Switzerland, November 9-10, 1998. 

Visconti A, Pascale M (1998) Determination of zearalenone in corn by means of immunoaffinity clean-up and high-performance liquid chromatography with fluorescence detection. 

McConnell RJ, Fitzgerald SP, Lamont JV (1992) Trenbolone and 19-nortestosterone residue analysis by immunoaffinity chromatography and high-performance liquid chromatography and/or an enzyme-linked immunosorbent assay. In Morgan MRA, Smith CJ, Williams PA (eds) Food safety and quality assurance applications of immunoassay systems. Elsevier, Barking, p 245... 

Fazekas, B. and Tar, A., Determination of zearalenone content in cereals and feedstuff s by immunoaffinity column coupled with liquid chromatography, J. AO AC Int., 84, 1453, 2001. 

Rhillips, T. M. S. R. D., Immunoaffinity analysis of substance R in complex biological fluids Analysis of submicroliter samples. Journal of Liquid Chromatography and Related Technologies 25, 2889-2900, 2002. 

Use of polyclonal antibodies in immunoaffinity cleanup of drug residues was first made in the determination of U enbolone in bovine urine by thin layer chromatography-liquid chromatography (TLC-LC) (173). The polyclonal antibody used was capable to bind both the active form 17- -trenbolone and its... 

For reliable identification of a residue, detailed information about the molecular structure of the analyte is essential. The total information about the molecular structure of the analyte is the sum of the information derived from each individual analytical step of tire method. Frequently used selective analytical steps based on chromatography or immunoaffinity, provide more or less general indirect information. For example, solid-phase extraction (SPE) cleanup followed by liquid chromatography/ultraviolet detection (LC/UV) has been suggested for screening and quantification of ivermectin residues in liver, but presumptive positive samples can be confirmed by derivatizing an aliquot of the SPE eluate and reanalyzing the fluorescent derivative of ivermectin in an LC-fluorescence system (17). 

Following initial sample extraction, the primary extract must frequently be subjected to some kind of further cleanup including liquid-liquid partitioning, diphasic dialysis, solid-phase extraction, matrix solid-phase dispersion, immunoaffinity chromatography cleanup, liquid chromatography cleanup, or online trace enrichment. In some instances, some of these procedures are used in combination in order to attain higher purification levels. 

The aqueous or organic extract obtained at this step of analysis may be a very dilute solution of the analyte(s) of interest. It may also contain coextractives, which, if allowed in the final extract, will increase the background noise of the detector, making it impossible to determine trace level concentrations of the analyte(s). To reduce interferences and concentrate the analyte(s), the primary sample extracts are subjected to some kind of cleanup including liquid-liquid partitioning, solid-phase extraction, matrix solid-phase dispersion, online trace enrichment, affinity chromatography, immunoaffinity chromatography, and ultrafiltration. In many instances, more than one of these procedures may be used in combination to increase extract purification. 

LC Liquid chromatography CB Contamination Bureau SPE solid-phase extraction TFA trifluoroacetic acid MS mass spectrometry OPA o-phthaldialdehyde IA immunoaffinity column FD fluorescence detector BF best food UV ultraviolet. 

B Zimmerli, R Dick. Determination of ochratoxin A at the ppt level in human blood, serum, milk and some foodstuffs by high-performance liquid chromatography with enhanced fluorescence detection and immunoaffinity column cleanup methodology and Swiss data. J Chrom B 666 85-99,1995. 

MW Trucksess, ME Stack, S Nesheim, SW Page, RH Albert, TJ Hansen, KF Donahue. Immunoaffinity column coupled with solution fluorometry or liquid chromatography post-column derivati-... 

Visconti A, Pascale M, Centonze G (2000) Determination of Ochratoxin A in Domestic and Imported Beers in Italy by Immunoaffinity Clean-Up and Liquid Chromatography. J Chromatogr A 888 321... 

W. Haasnoot, M. E. Ploum, R. J. A. Paulussen, R. Schilt and F. A. Huf, Rapid determination of clenbuterol residues in urine by high performance liquid chromatography with on-line automated sample processing using immunoaffinity chromatography , J. Chromatogr. 519 323-335 (1990). 

A. Farjam, A. E. Brugman, A. Soldaat, P. Timmerman, H. Lingerman, G. J. de Jong, R. W. Frei and U. A. Th Brinkman, Immunoaffinity precolumn for selective sample pretreatment in column liquid chromatography immunoselective desorption , Chromatographia 31 469-477 (1991). 

J. Cai and J. Henion, Quantitative multi-residue determination of /3-agonists in bovine urine using on-line immunoaffinity extraction-coupled column packed capillary liquid chromatography-tandem mass spectrometry , 7. Chromatogr. 691 357-370 (1997). 

C. S. Creaser, S. J. Feely, E. Houghton and M. Seymour, Immunoaffinity chromatography combined on-line with high performance liquid chromatography-mass spectrometry for the determination of corticosteroids , 7. Chromatogr. 794 37-43 (1998). 

A. Farjam, N. C. van de Merbel, A. A. Nieman, H. Lingeman and U. A. Th Brinkman, Determination of aflatoxin Ml using a dialysis-based immunoaffinity sample pretreatment system coupled on-line to liquid chromatography , J. Chromatogr. 589 141-149(1992). 

V. Kircher and H. Parlar, Determination of A9 tetrahydrocannabinol from human saliva by tandem immunoaffinity chromatography-high-performance liquid chromatography , J. Chromatogr. B 677 245 - 255 (1996). 

G. S. Rule and J. D. Henion, Determination of drugs from urine by on-line immunoaffinity chromatography-high-performance liquid chromatography-mass spectrometry , J. Chromatogr. 582 103-112 (1992). 

For small molecule analytes (see Note 6) for which a radiotracer form is available, sequentially load a known quantity of tracer dissolved in buffer and determine the amount of analyte in the eluant. When the radioactivity not retained by the immunoaffinity column plateaus, the column binding sites are saturated. Wash the column, and elute the retained radioactivity. The mass of analyte in the eluted volume is the apparent column capacity. In many instances a radio-labeled analyte may not be available. In such cases, high-performance liquid chromatography, UV spectroscopy, or any other analytical tool capable of selectively quantifying the analyte may be used to determine column capacity. 

As an alternative, immunoaffinity procedures have been developed to selectively extract PAHs from environmental samples. Thomas and Li62 demonstrated the greater efficiency of immunoaffinity methods in comparison with conventional extraction procedures. Bouzige et al.48 prepared an immunosorbent for use in an on-line analytical procedure, followed by liquid chromatography coupled to fluorescence detection, to monitor surface water samples. The sensitivity of the fluorescence detection in combination with the selectivity of the immunosorbent (IS) extraction enabled PAH compounds to be detected at levels between 2 and 10 ng I. 

Kussak, A. et al., Determination of aflatoxicol in human urine by immunoaffinity column clean-up and liquid chromatography, Chemosphere, 36, 1841-1848, 1998. 

Queiroz ME, Oliveira EB, Breton F et al (2007) Immunoaffinity in-tube solid phase microextraction coupled with liquid chromatography-mass spectrometry for analysis of fluoxetine in serum samples. J Chromatogr A 1174 72-77... 

Chapter 15 provides an in-depth coverage of various chromatographic methods, such as ion exchange, hydrophobic interaction, affinity, ligand, immunoaffinity, gel filtration, etc., that can be used for separations of antibodies by liquid chromatography. 

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