Micro HPLC

Dugo, P. et al.. Characterization of the anthocyanin fraction of Sicilian blood orange juice by micro-HPLC-ESI/MS, J. Agric. Food Chem., 51, 1173, 2003. 

Figure 10 Real-time plot of reactor component concentrations in catalytic hydrogenation step illustrating early detection of baseline upset by on-line micro-HPLC.

Trisciani, A. and Andreolini, F, Evaluation of a micro-HPLC system dedicated to packed capillary column liquid chromatography, /. HRC CC, 13,270,1990. 

M. Yoshioka, S. Parvez, T. Miyazaki and H. Parvez, Supercritical Fluid Chromatography and Micro HPLC, VSP, Utrecht (1989). 

Use of FID and SCD are compatible with SFE-HPLC, since they are flame-based and unaffected by gases in the mobile phase. Unfortunately, SCD can only be used with micro-HPLC (column i.d. <320 (tm), which requires miniaturised equipment not commonly found in most analytical laboratories. When following SFE with HPLC analysis using a spectroscopic detector, a medium-purity grade is usually sufficient. 

Terada, H., Suzuki, A., Tanaka, H., and Yamamoto, K., Determination of cat-echins and methylxanthines in foods by semi-micro HPLC, J. Food Hygienic Soc. Jpn., 33(4),347,1992... 

Column diameter is an important parameter to consider in life science applications in which sample amounts are very limited and the components of interest may not be abundant. Researchers have reviewed micro HPLC instrumentation and its advantages.910 Nano LC-MS offers 1000- to 34,000-time reductions in the dilution of a sample molecular zone eluted from nano LC columns of 25 to 150 [Mi IDs in comparison to a 4.6 mm ID column. This represents a large enhancement of ion counts in comparison to counts obtained for the same amount of sample injected into a conventional 4.6 mm column. Solvent consumption for an analysis run or sample amount required for injection in a nano LC application may be reduced 1000 to 34,000 times compared to amounts required by an analytical column operated at a 1 mL/min flow rate. 

D. Jin, H. Hakamata, K. Takahashi, A. Kotani and F. Kusu, Determination of quercetin in human plasma after ingestion of commercial canned green tea by semi-micro HPLC and electrochemical detection. Biomed. Chromatogr. 18 (2004) 662-666. 

Fig. 3.107. Comparison of micro-HPLC separations of aromatic sulphonic acids in different mobile phases (a) 0.005 M tetrabutylammonium hydrogensulphate (TBAS) in 15 per cent (v/v) methanol in water (1) Laurent acid, (2) amino-F-acid, (3) Cleve-1,6- and Peri acids, (4) unidentified impurity, (5) Cleve-1,7-acid and (6) unidentified impurity, (b) 0.005 M tetrabutylammonium hydrogensulphate (TBAS) in 15 per cent (v/v) methanol in water with 0.01 M /Lcyclodextrin (CD) (1) Laurent acid, (2) amino-F-acid, (3) Cleve-1,6-acid, (4) Peri acids, (5) unidentified impurity, (6) Cleve-1,7-acid and (7) unidentified impurity. Column, Biosphere Si C18, 162 X 0.32 mm i.d. flow rate 5 pl/min, column temperature ambient, detection, UV, 220-230 nm. Reprinted with permission from P. Jandera et al. [164].

FIGURE 1.30 Micro-HPLC separation of all 4 stereoisomers of the dipeptide alanyl-alanine as FMOC derivatives (a) and DNP-derivatives (b), respectively, on a 0-9-(tert-butylcarbamoyl)quinine-based CSP. Experimental conditions Column dimension, 150 X 0.5 mm ID mobile phase (a) acetonitrile-methanol (80 20 v/v) containing 400 mM acetic acid and 4 mM triethylamine, and (b) methanol-0.5 M ammonium acetate buffer (80 20 v/v) (pHa 6.0) flow rate, 10 ixLmin temperature, 25 C injection volume, 250 nL detection, UV at 250 nm. (Reproduced fromC. Czerwenka et al., J. Pharm. Biomed. Anal., 30 1789 (2003). With permission.)... 

Piccinini, A.-M., Chiral separation of natural and unnatural amino acid derivatives by micro-HPLC on a ristocetin A stationary phase, J. Biochem. Biophys. Methods, 61, 11,2004. 

Grobuschek, N. et al., Enantioseparation of amino acids and drugs by CEC, pressure supported CEC, and micro-HPLC using a teicoplanin aglycone stationary phase, J. Sep. ScL, 25, 1297, 2002. 

Schmid, M.G. et al., Enantioseparation of dipeptides and tripeptides by micro-HPLC comparing teicoplanin and teicoplanin aglycone as chiral selectors, J. Bio-chem. Biophys. Methods, 61, 1,2004. 

Buszewski, B., Szumski, M., and Sus, S. (2002). Methacrylate-based monolithic columns for micro-HPLC and CEC. LC-GC Europe 15, 792-798. 

High-performance liquid chromatography (HPLC) has become a standard separation technique used in both academic and commercial analytical laboratories. However, there are several drawbacks to standard HPLC, including high solvent consumption, large sample quantity, and decreased detection sensitivity. Micro-HPLC (pHPLC) is a term that encompasses a broad range of sample volumes and column sizes (as shown in Table 3.1), but Saito and coworkers provided narrower definitions in their review based on the size of the columns. ... 

Dugo, R, Presti, M. L., Ohman, M., Fazio, A., Dugo, G., and Mondello, L., Determination of flavonoids in citrus juices by micro-HPLC-ESI/MS, Journal of Separation Science 28(11), 1149-1156, 2005. 

Perbellini, L., Gottardo, R., Caprini, A., Bortolotti, F., Mariotto, S., and Tagliaro, F., Determination of alpha-bisabolol in human blood by micro-HPLC-ion trap MS and head space-GC-MS methods. Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences 812(1-2), 373-377, 2004. 

Kotani, A., Kojima, S., Hakamata, H., Jin, D., and Kusu, R, Determination of honokiol and magnolol by micro HPLC with electrochemical detection and its application to the distribution analysis in branches and leaves of Magnolia obovata. Chemical and Pharmaceutical Bulletin (Tokyo) 53(3), 319-322, 2005. 

Sultan, M., Stecher, G., Stoggl, W. M., Bakry, R., Zahorski, P, Huck, C. W., El Kousy, N. M., and Bonn, G. K., Sample pretreatment and determination of non steroidal anti-inflammatory drugs (NSAIDs) in pharmaceutical formulations and biological samples (blood, plasma, erythrocytes) by HPLC-UV-MS and micro-HPLC, Current Medicinal Chemistry 12(5), 573-588, 2005. 

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