Clinical liquid chromatography

Kabra, P.M. and Marton, L.J. (1984) Clinical Liquid Chromatography, Vols. I and II, CRC Press, Boca Raton, FL. 

Clinical. Liquid Chromatography Clinical Applications Pharmaceutical Applications. Microscopy Overview. Pharmaceutical Analysis Overview. Sensors Overview. 

Preanalytical Specimen Handling in Clinical Liquid Chromatography... 

PREANALYTICAL SPECIMEN HANDLING IN CLINICAL LIQUID CHROMATOGRAPHY... 

In the ED setting, the diagnosis of ketamine intoxication is a clinical one. Ketamine is not routinely detected by urine toxicology tests, although it can be detected with high-performance liquid chromatography (Koesters et al. 2002). As with MDMA, the initial assessment for ketamine intoxication includes the use of routine laboratory tests to detect electrolyte abnormalities and to evaluate renal and hepatic functioning (Koesters et al. 2002). 

General Description. Liquid chromatography encompasses any chromatographic method in which the mobile phase is a liquid (c.f. gas chromatography). A variety of stationary phases and retention mechanisms are available such that a broad range of modes of separation are possible. It is worthwhile to briefly describe the important modes that find use in clinical chemistry. 

Successful use of modern liquid chromatography in the clinical laboratory requires an appreciation of the method s analytical characteristics. The quantitative reproducibility with respect to peak height or peak area is quite good. With a sample loop injector relative standard deviations better than 1% are to be expected. The variability of syringe injection (3-4% relative standard deviation) requires the use of an internal standard to reach the 1% level (2,27). 

This introduction to modem liquid chromatography should suggest some of the roles LC might play in clinical analysis. 

In this study, Ali and Aboul-Enein [80] used cellulose tr is (3,5-d ich Ioropheny 1 carbamate) chiral stationary phase for the enantioseparation of miconazole and other clinically used drugs by high performance liquid chromatography. The mobile... 

Hu C. et al., 2006. Clinical-scale high-throughput analysis of urinary 8-oxo-7,8-dihydro-2 -deoxyquanosine by isotope-dilution liquid chromatography-tandem mass spectrometry with online sohd-phase extraction. Clin Chem 52 7. 

Consider one small molecule, phenylalanine. It is an essential amino acid in our diet and is important in protein synthesis (a component of protein), as well as a precursor to tyrosine and neurotransmitters. Phenylalanine is one of several amino acids that are measured in a variety of clinical methods, which include immunoassay, fluorometry, high performance liquid chromatography (HPLC see Section 4.1.2) and most recently MS/MS (see Chapter 3). Historically, screening labs utilized immunoassays or fluorimetric analysis. Diagnostic metabolic labs used the amino acid analyzer, which was a form of HPLC. Most recently, the tandem mass spectrometer has been used extensively in screening labs to analyze amino acids or in diagnostic labs as a universal detector for GC and LC techniques. Why did MS/MS replace older technological systems The answer to this question lies in the power of mass spectrometer. 

P. Marquet. Progress of Liquid Chromatography-Mass Spectrometry in Clinical and Forensic Toxicology, Therapeutic Drug Monitoring, 24, no. 2, (2002). 

Derivatization, i.e. reaction of the analyte with a reagent leading to a fluorescent compound, is often used in conjunction with liquid chromatography with fluorescence detection. This method is currently used in biochemistry and clinical... 

Smyth WE, Brooks P. 2004. A critical evaluation of high performance liquid chromatography ionization-mass spectrometry and capillary electrophoresis-electrospray-mass spectrometry for the detection and determination of small molecules of significance in clinical and forensic science. Electrophoresis 25 1413. 

High-pressure liquid chromatography method development of pharmaceuticals is an iterative process required to support successive phases of pharmaceutical development and clinical studies. This chapter details the approach currently in use in our laboratories, from receipt of a new chemical entity to post transfer support. 

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