Bioanalytical samples

D.A. Wells, High Throughput Bioanalytical Sample Preparation Method and Automation Strategies, Elsevier, The Netherlands, 2003. 

Use Internal Standards for bioanalytical samples to compensate for sample loss dnring sample preparation. The internal standards shonld have similar structures to the analytes and in most cases are isotopically labeled analytes. 

J. Wieling, H. Dijkstra, C.K. Mensink, J.H.G. Jonkman, P.M.J. Coenegracht, C.A.A. Duineveld and D.A. Doombos, Chemometrics in Bioanalytical Sample Preparation a Fractionated Combined Mixture and Factorial Design for the Modelling of the Recovery of Five Tricyclic Amines from Plasma after Liquid-Liquid Extraction, Journal of Chromatography, 629(2) (1993) 181-199. 

Figure 1.28. Generic quantitative bioanalytical sample preparation scheme. (SPE — solid phase extraction LLE - liquid-liquid extraction PPT—protein precipitation). (Reprinted with permission from Chang et al., 2007a.)...

Paper published in September, 2007 by Rocci et al. entitled Confirmatory Reanalysis of Incurred Bioanalytical Samples [24],... 

Rocci ML, Devanarayan V, Haughey DB et al (2007) Confirmatory reanalysis of incurred bioanalytical samples. AAPS J 9(3) E336-E343... 

The described evaluation provides a tool, also called online PK , which allows adjusting the dose in this first-in-man study on a very flexible basis. Consequently, this flexible dose-scheme is described already in the study protocol. The main prerequisite is, besides an adjustable dosing form, an immediate shipping and evaluation of the bioanalytical samples. 

Wells, D. A. (2003) High throughput bioanalytical sample preparation. Methods and Automation Strategies. Progress in Pharmaceutical and Biomedical Analysis, Vol. 5, Elsevier, Amsterdam, NL. 

As bioanalytical samples are usually measured in millilitres it is more convenient to use the following equation ... 

Jonsson OB, Nordldf U, and Nilsson UL. The XT-tube extractor A hollow Hber-based supported liquid membrane extractor for bioanalytical sample preparation. Anal. Chem. 2003 75 3506-3511. 

For pharmaceutical applications, the term bioanalysis refers to quantitative determination of a drug or its metabolites in a biological matrix. Although this term has traditionally been used to describe the analysis of in vivo samples (i.e., plasma or serum), current use of the term encompasses a broader range of applications that include the analysis of in vitro samples. Under this broader dehnihon, possible bioanalytical sample types can range anywhere from transport media to tissue homogenate. 

Lensmeyer, G.L. Oroskar, A. Evaluation Model for Identification of Distinctive Silanol Variations in SPE Sorbents Used for LC-MS/MS Bioanalytical Sample Preparation, in Proceedings ofthe 50th ASMS Conference on Mass Spectrometry and Allied Topics, Orlando, FL, June 2-6,2002. 

Many different sample-preparation techniques are available to a drug-discovery scientist performing bioanalytical sample preparation. These techniques vary in several regards, such as simplicity (number of steps), time requirement, materials cost per sample, expertise of the analyst, ease of method development, ability to be automated, concentration factor attained, and cleanliness of the final extract. It is important to note that the sample-preparation needs within drug discovery are different from those in other phases of drug development. In drug discovery, new compounds are introduced as often... 

Ungerstedt, U. Microdialysis-a new bioanalytical sampling technique, Curr. Sep., 7, 43M6 (1986). 

Gu, H., Unger, S., and Deng, Y. (2006) Automated Tecan programming for bioanalytical sample preparation with EZTecan. Assay and Drug Development Technologies, 4, 721 733. 

Bioanalytical sample analysis by LC/MS/MS remains a rate-limiting step in many ADME processes, including transporter evaluation. The number of injection samples and MS run time can escalate rapidly and depend on whether compounds are tested in duplicate or triplicate and the number of points generated for a standard curve. For example, if one compound is evaluated in parental and MDRl-transfected cell lines in triplicate in both directions, 12 samples are generated from both apical and basolateral compartments. Add in an eight-point standard curve (1 500 nM), dose solutions, wash injections in-between triplicates, and approximately 58 injection samples per compound would result If each injection were approximately 3 min per run, then each... 

Ungerstedt U (1986) Microdialysis - a new bioanalytical sampling technique. Current Separations 7 43—46. 

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