Biological samples analysis

The field of steroid analysis includes identification of steroids in biological samples, analysis of pharmaceutical formulations, and elucidation of steroid stmctures. Many different analytical methods, such as ultraviolet (uv) spectroscopy, infrared (ir) spectroscopy, nuclear magnetic resonance (nmr) spectroscopy, x-ray crystallography, and mass spectroscopy, are used for steroid analysis. The constant development of these analytical techniques has stimulated the advancement of steroid analysis. 

Zhou S. et al., 2005. High-throughput biological sample analysis using online turbulent flow extraction combined with monothic column liquid chromatography/tandem mass spectrometry. Rapid Commun Mass Spectrom 19 2150. 

Elias Z, Mur JM, Pierre F, et al. 1989. Chromosome aberrations in peripheral blood lymphocytes of welders and characterization of their exposure by biological samples analysis. J Occup Med 31 477-483. 

Zhou, S., Zhou, H., Larson, M., Miller, D. L., Mao, D., Jiang, X., and Naidong, W. (2005). High-throughput biological sample analysis using on-line turbulent-flow extraction combined with monolithic column liquid chromatography/tandem mass spectrometry. Rapid Commun. Mass Spectrom. 19 2144-2150. 

Mass spectrometers are used not only to detect the masses of proteins and peptides, but also to identify the proteins, to compare patterns of proteins and peptides, and to scan tissue sections for specific masses. MS is able to do this by giving the mass-to-charge ratio of an ionized species as well as its relative abundance. For biological sample analysis, mass spectrometers are connected to an ionizing source, which is usually matrix-assisted laser desorption ionization (MALDI) [14], surface-enhanced laser desorption/ioni-zation (SELDI, a modified form of MALDI) [15], or electrospray ionization [16]. These interfaces enable the transfer of the peptides or proteins from the solid or liquid phase, respectively, to the gas (vacuum) phase inside the mass spectrometer. Both MALDI and electrospray ionization can be connected to different types of mass analyzers, such as quadrupole, quadruple-ion-traps, time of flight (TOF), or hybrid instruments such as quadrupole-TOF or Fourier transform-ion cyclotron resonance. Each of these instruments can... 

Am(in) CMPO + TBP HNO3 HCOOH + HAF Biological sample analysis done using three-compaitment cell [108]... 

J. Shiea, C.-H. Wang, Applications of multiple channel ESI sources for biological sample analysis, J. Mass Spectrom., 32 (1997) 247. 

Validation of biological sample analysis methods is critical to the evaluation of the final data. A description of the validation procedure utilized by the NTP is provided here. The method needs to demonstrate the appropriate specificity, precision, absolute recovery, measurement limits, and relative error. An evaluation of the blank biological sample matrix contribution to responses seen in spiked samples also needs to be determined. 

Liquid-liquid extraction (LLE) or liquid-liquid partitioning (LLP) was one of the first sample preparation techniques and continues to be widely used for biological sample analysis. LLE is based on the transfer of analyte from the aqueous sample to a water-immiscible solvent based on the octanol-water partition coefficient. Nevertheless, some shortcomings, such as emulsion formation, the use of large sample volumes, and toxic organic solvents and above all, the production of a large volume of hazardous waste, make LLE expensive, time-consuming, and environmentally harmful. Another drawback of LLE is its unsuitability for hydrophilic compounds. ... 

Table 20.1. Selected Applications of MALDl-TOF MS to Biological Sample Analysis...

Biological sample analysis by ICP-MS is not without problems. In biological samples, interferences from atomic and molecular ions produced in the plasma from argon and matrix constituents of the aspirated solutions plague the quantification of several elements,3- e.g. ai/i cI N/ cI NH, k/ SAtIH, CaJ Ar, As/ Ar Sci,... 

Holmes, M.G., An outdoor multiple wavelength system for the irradiation of biological samples analysis of the long-term performance of various lamps and filter combinations, Photochem. Photobiol, 76, 158, 2002. 

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