Analysis of drug-, and metabolites

Gudzinowicz, B. J. and Gudzinowicz, M. J. Analysis of Drugs and Metabolites by Gas Chromatography Mass Spectrometry (Vols. 1-5). New York Marcel Dekker, 1977. 

Cherkaoui, S., Rudaz, S., Varesio, E., and Veuthey, J. L. (2001). On-line capillary electrophoresis-electrospray mass spectrometry for the stereoselective analysis of drugs and metabolites. Electrophoresis 22, 3308—3315. 

Drexler D, Garrett T, Cantone J, Diters R, Mitroka J, Conaway M, Adams S, Yost R, Sanders M (2007) Utility of imaging mass spectrometry (IMS) by matrix-assisted laser desorption ionization (MALDI) on an ion trap mass spectrometer in the analysis of drugs and metabolites in biological tissue. J Pharmacol Toxicol Methods 55 279-288. doi 10.1016/j. vascn.2006.11.004... 

Moriya, R, Miyaishi, S., and Ishizu, H., Presumption of an history of methamphetamine abuse by postmortem analyses of hair and nails a case report, Jpn. ]. Alcohol Drug Depend., 27,152,1992. Nakahara, Y., Kikura, R., Takahashi, K., and Kunoma, K., GC/MS analysis of drugs and metabolites in hair for diagnosis of chronic methamphetamine abuse, Adv. Chem. Diagnos. Treat. Metab. Disord., Matsumoto, Ed., London, 1994,187. 

The analytical process can be divided into four major steps sample preparation, separation, detection, and data treatment. Eor the analysis of drugs and metabolites in biological matrices, sample preparation remains the most challenging task since the compounds of interest are often present at trace level in a complex matrix containing a large number of biomolecules (e.g. proteins) and other substances, such as salts. 

The analysis of drugs and metabolites in biological fluids, particularly plasma or serum is one of the most demanding but one of the most common uses of HPLC. Blood, plasma or serum contain numerous endogenous compounds often present at concentrations much greater than... 

Another current trend that is well underway is the use of more specific analytical instrumentation that allows less extensive sample preparation. The development of mass spectrometric techniques, particularly tandem MS linked to a HPLC or flow injection system, has allowed the specific and sensitive analysis of simple extracts of biological samples (68,70-72). A similar HPLC with UV detection would require significantly more extensive sample preparation effort and, importantly, more method development time. Currently, the bulk of the HPLC-MS efforts have been applied to the analysis of drugs and metabolites in biological samples. Kristiansen et al. (73) have also applied flow-injection tandem mass spectrometry to measure sulfonamide antibiotics in meat and blood using a very simple ethyl acetate extraction step. This important technique will surely find many more applications in the future. 

Luminescence spectroscopy is an analytical method derived from the emission of light by molecules which have become electronically excited subsequent to the absorption of visible or ultraviolet radiation. Due to its high analytical sensitivity (concentrations of luminescing analytes 1 X 10 9 moles/L are routinely determined), this technique is widely employed in the analysis of drugs and metabolites. These applications are derived from the relationships between analyte concentrations and luminescence intensities and are therefore similar in concept to most other physicochemical methods of analysis. Other features of luminescence spectral bands, such as position in the electromagnetic spectrum (wavelength or frequency), band form, emission lifetime, and excitation spectrum, are related to molecular structure and environment and therefore also have analytical value. 

The advent of API MS has revolutionized the analysis of drugs and metabolites in biological samples. The API source provides an ideal interface to link HPLC to MS utilizing two ionization methods electrospray ionization (ESI), which ionizes the molecules in the mobile phase, before the ions arrive in the gas phase, and atmospheric pressure chemical ionization (APCI), which ionizes the molecules after they are already in the gas phase. In APCI mode, both solvent and solutes are rapidly evaporated by heat. After evaporation of neutral species, ions are formed in a gas phase at atmospheric pressure. All species in the gas phase undergo... 

ELECTROKINETIC TECHNIQUES FOR THE ANALYSIS OF DRUGS AND METABOLITES IN BODY FLUIDS... 

In addition to UV detection, two other more sensitive and selective detection systems have attracted attention for the analysis of drugs and metabolites in biological samples laser-induced fluorescence (LIF) and mass spectrometry (MS). A powerful detection system is that which is based on LIF. The LIF detection provides extremely high mass sensitivity, but it is only applicable to some analytes that absorb in the 325 nm (helium-cadmium) or 488 nm (argon) region, as lasers are only commercially available for these wavelengths. Derivatization with fluorescent tags is an alternative for non-fluorescent species. "- ... 

Kertesz, V., Van Berkel, G.J. (2010) Liquid Microjunction Surface Sampling Coupled with High-Pressure Liquid Chromatography-Electrospray Ionization-Mass Spectrometry for Analysis of Drugs and Metabolites in Whole-body Thin Tissue Sections. Anal. Chem. 82 5917-5921. 

R. Whelpton and P.R. Hurst, HPLC-EC analysis of hyoscine (scopolamine) in urine, in Analysis of Drugs and Metabolites, Including Anti-infective Agents, R. Reid and I.D. Wilson, (eds) Royal Society of Chemistry, Cambridge, 1990, 279-284. 

Analysis of Drugs and Metabolites by Gas Chromatography-Mass Spectrometry... 

Liquid chromatography coupled to mass spectrometry and tandem mass spectrometry (LC/MS and LC/MS/MS) lead to major breakthroughs in the field of quantitative bioanalysis due to high specificity, sensitivity, speed, and reliability, which becomes the preferred analytical tools for analysis of drugs and metabolites in biological matrices. A simple and rapid method has been developed and validated for the quantitation of vincristine in human plasma by LC/MS/MS with atmospheric pressure chemical ionization using on-line solid-phase extraction. The method uses vinblastine as internal standard and the sample preparation is... 

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