Chiral analysis

Isocratic or gradient HPLC with MS/MS detection SPE, protein precipitation, liquid-liquid extraction, or online clean up typically using the 96-well microplate format Internal standardization based on a stable isotope-labeled analog of the analyte is prefered Accuracy three levels, five determinations each 15-20% of the spiked values 

Precision three levels, five determinations each NMT 15-20% RSD, intraday and interday precision Specificity analytes resolved from other metabolites 

Linearity Regression coefficient of calibration curve 0.95 based on 6-8 levels covering the entire dynamic range Stability room temperature, frozen storage, freeze/thaw, in biological matrices (high and low level in triplicates). Stability of standard solution and stability of samples in autosampler also required). 

Column CHIROBIOTIC Tcolumn (250 x4.6mm) Mobile ph. 70% methanol, 30% water, 

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We can list the following areas as prime targets essential oil and natural product analysis, chiral analysis (e.g. of fragrances), trace multi-residue analysis, pesticide monitoring, and further petroleum products applications, in fact any separation where simply greater resolution and sensitivity is demanded-which means probably almost... 

B. Chankvetadze, Capillary Electrophoresis in Chiral Analysis, Jolm Wiley Sons, New Yoi-k (1997). 

The difference in resolution between LC and SFC can be significant enough to turn a marginal LC separation into a viable chromatographic method in SFC. String-ham et al. reported that packed column SFC yielded satisfactory chiral analysis... 

Nokihara K, Gerhardt J Development of an improved automated gas-chromatographic chiral analysis system application to non-natural amino acids and natural protein hydrolysates. Chirality 2001 13 431. 

Capillary electrophoresis is still in a state of evolution and a technique of choice for certain applications (chiral analysis small ion analysis in food and beverage industries bioanalysis). The number of reviews [365,858,884,889-896], books and manuals [365,897-903] published on (HP)CE/CEC/CZE in the last decade is overwhelming, in particular in relation to the importance of the technique (see also Bibliography). CE-LIFS has been reviewed [904]. 

Mass spectrometry (MS) is also being used to add another dimension of analysis to achiral-chiral analysis. Recently, an achiral-chiral column-switching LC/LC-MS/MS method was reported for the pindolol enantiomers in human serum (Motoyama et al., 2002) and phenprocoumon metabolites (Kammerer et al., 1998). For analytes that have very poor chromophores or cannot naturally fluoresce, MS detection can be more sensitive for the underivatized form of the analyte. Also, MS detection can be particularly useful when very similar analytes that differ in mass (such as some amino acids and metabolites) cannot be satisfactorily separated chromatographically,... 

Natural configuration Method for chiral analysis Field attraction Optimum isomer a Racemate b [Reference]... 

Chiral analysis for ee determination was by normal-phase high-performance liquid chromatography with a Chiralcel OD-H column using 98 % hexanes/2 % 2-propanol at 1 mL min 25 °C and monitoring at 265 nm. 

The organic fraction was collected and 1 /rL of the solution was submitted to the GC-MS for qualitative and chiral analysis to certify conversion to 1-indanol. 

Aboul-Enein, H.Y. and Hefnawy, M.M., Chiral analysis of butaclamol enantiomers in human plasma by HPLC using a macrocychc antibiotic (vancomycin) chiral stationary phase and sohd phase extraction. Chirality, 16, 147, 2004. 

An experimental design approach was also used in Reference 26 for the chiral analysis of amino acid derivatives. The screening and optimization schedule followed... 

Perrin, C., Vargas, M.G, Vander Heyden, Y., Maftonh, M., Massarf D.L. Fast development of separation methods for the chiral analysis of amino acid derivatives using capillary electrophoresis and experimental designs. J. Chromatogr. A 2000, 883, 249-265. 

Sonverain, S., Geiser, L., Rudaz, S., Venthey, J.-L. Strategies for rapid chiral analysis by capillary electrophoresis. J. Pharm. Biomed An. 2006, 40, 235-241. 

Amino acids (chiral analysis) Pentafluoracetic anhydride Heptafluorobutyryl anhydride Esterification with deuterium Nkoihara and... 

CE has been touted as a replacement for HPLC in the pharmaceutical industry. This was a shame, since the techniques are so different. For many measurements, it is an orthogonal technique to HPLC. Whereas HPLC separates based on interaction with the stationary phase, CE separates based on the ratio of charge to mass. There are numerous examples of where CE exceeds the resolving power of HPLC (e.g., ion analysis, chiral analysis, DNA quantification, separation, large molecule analysis, etc.). 

Altria, K. D., Harden, R. C., Hart, M., Hevizi, J., Hailey, P. A., Makwana, J. V., and Portsmouth, M. J. (1993). Inter-company cross-validation exercise on capillary electrophoresis. I. Chiral analysis of... 

Garcia-Ruiz, C., and Marina, M. L. (2006). Sensitive chiral analysis by capillary electrophoresis. Electrophoresis 27, 195—212. 

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