Plasma analytes

The ionization energy of Ar is 15.8 electron volts (eV), which is higher than those of all elements except He, Ne, and F. In an Ar plasma, analyte elements can be ionized by collisions with Ar+, excited Ar atoms, or energetic electrons. In atomic emission spectroscopy, we usually observe the more abundant neutral atoms, M. However, the plasma can be directed into a mass spectrometer (Chapter 22), which separates and measures ions according to their mass-to-charge ratio.17 For the most accurate measurements of isotope ratios, the mass spectrometer has one detector for each desired isotope.18... 

B7. Benzie, I. F., Chung, W., and Tomlinson, B., Simultaneous measurement of allantoin and urate in plasma Analytical evaluation and potential clinical application in oxidant antioxidant balance studies. Clin. Chem. 45, 901—904 (1999). 

Both prerenal factors (dehydration, blood loss, altered vasomotor tone, age-related decreases in renal blood flow in rats) and postrenal factors (obstruction or extravasation of urine to the peritoneal cavity) may cause elevations of the commonly measured analytes that do not reflect primary kidney injury. Plasma analytes also cannot be used to determine the location of renal injury (glomerular versus tubular, or tubular segment affected) (Baum et al. 1975 Corman and Michel 1987 Finco 1997 Newman and Price 1999). 

The degree of azotemia is assessed by measuring urea and/or creatinine levels in blood samples obtained at intervals of 2-6 days after surgery. Plasma analytes are compared between operated and sham-operated animals. Histological examination is performed after sacrifice of the animals. 

Yu, R.Z., Baker, B., Chappell, A., Geary, R.S., Cheung, E., and Levin, A.A. (2002) Development of an ultrasensitive noncompetitive hybridization ligation enzyme linked immunosorbent assay for the determination of phosphorothioate oligodeoxy nucleotide in plasma. Analytical Biochemistry, 304, 19 25. 

Bengtsson, H., Roos,U.,and Andersson, L.I. (1997) Molecular imprint based radioassay for direct determination of S propranolol in human plasma. Analytical Communications, 34, 233 235. 

In summary, the use of DPP and an electroactive label resulted in a competitive homogeneous immunoassay with a detection limit in the 100 ng/ml range. Although application to estriol is not feasible, the direct analysis of urinary samples for other analytes in this concentration range would be possible. The analysis of plasma analytes may or may not require a cleanup step, depending on the analyte involved. 

Hsieh,Y,Duncan,C.J.G.,Brisson,J.M. (2007) Fused-core silica column high-performance hquid chromatography/ tandem mass spectrometric determination of rimonabant in mouse plasma. Analytical Chemistry, 79,5668-5673. 

Xu, Y., Mehl, IT, Bakhtiar, R., et al. (2010) Immunoaffi-nity purification using anti-PEG antibody followed by two-dimensional liquid chromatography/tandem mass spectrometry tor the quantification of a PEGylated therapeutic peptide in human plasma. Analytical Chemistry, 82, 6877-6886. 

The aim of this section is to discuss applications of HPLC-ED in the analysis of drugs and their metabolites in biological specimens, usually plasma. Analytes (International Nonproprietary Names, INNs are used when possible) are listed mainly by pharmacological category. Chemical structures are given for most analytes and internal standards, as are ED conditions, column, eluent, sample size and limit of detection (LoD) and low limit of quantitation (LLoQ). Brief details of sample preparation procedures are also included in many instances. 

Nelson, B.C., Pfeiffer, C.M., Margolis, S.A., and Nelson, C.P., 2003. Affinity extraction combined with stable isotope dilution LC/MS for the determination of 5-methyltetrahydrofolate in human plasma. Analytical Biochemistry. 313 117-127. 

Vaisocherova, H., Yang, W., Zhang, Z., Cao, Z., Cheng, G., PUiarik, M., et al. (2008). Ultralow fouling and functionahzable surface chemistry based on a zwitterionic polymer enabhng sensitive and specific protein detection in undiluted blood plasma. Analytical Chemistry, 80,7894—7901. 

Industrial Analysis with Vibrational Spectroscopy 5 Ionization Methods in Organic Mass Spectrometry 6 Quantitative Millimetre Wavelength Spectrometry 7 Glow Discharge Optical Emission Spectroscopy A Practical Guide 8 Chemometrics in Analytical Spectroscopy, 2nd Edition 9 Raman Spectroscopy in Archaeology and Art History 10 Basic Chemometric Techniques in Atomic Spectroscopy 11 Biomedical Applications of Synchrotron Infrared Microspectroscopy 12 Microwave Induced Plasma Analytical Spectrometry 13 Basic Chemometric Techniques in Atomic Spectroscopy, 2" Edition... 

K. J. Jankowski and E. Reszke, Microwave Induced Plasma Analytical Spectrometry, RSC Analytical Spectroscopy Monographs, The Royal Society of Chemistry, Cambridge, UK, 2011. 

Jankowski, J. Reszke, E. Burnell, N. W. Midowave Induced Plasma Analytical Spectrometry, RSC Publishing Cambridge, 2011. 

Nicholson JK, Foxall PJD, Spraul M, Farrant RD and Lindon JC (1995) 750 MHz H and H-i C NMR spectroscopy of human blood plasma. Analytical Chemistry 67 793-811. 

Houk RS (1986) Mass spectrometry of inductively coupled plasmas. Analytical Chemistry 97A-105A. 

Guan, E, Uboh, C.E., Soma, L.R., et al. (2007) LC-MS/MS method for confirmation of recombinant human erythropoietin and darbepoetin alpha in equine plasma. Analytical Chemistry, 79,4627 635. 

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