Micro-bore columns —

Today nearly all of the major HPLC companies offer a pHPLC system or at least the possibility to modify a standard instrument to accept micro-bore columns. In our laboratory, we routinely use the pHPLC systems Ultimate from Dionex/LC Packing (Ligure 3.2), the Extreme Simple 4-D... 

In addition to the commercially available systems, several authors have described laboratory-built systems using commercially available components from companies such as Upchurch Scientific (Oak Harbor, WA). One of the first reported laboratory-built micro-bore HPLC systems was described by Simpson and Brown, which was a simple adaptation of a standard HPLC system to accept micro-bore columns built from guard columns. A complete system has been described based on dual microdialysis syringe pumps (CMA Microdialysis, Chelmsford, M A) or dual syringe pumps (Harvard Apparatus, Inc., Holliston, MA), a microinjection port, and a micro-column the latter components being obtained from Upchurch scientific (Figure 3.5). This system was coupled with a laser-induced fluorescence (LIF) detector and used to measure neuropeptides in sub-microliter samples. A further modification of this system was built to perform immunoaffinity isolations of biomedically important analytes from clinical samples. ... 

D. T. Gjerde, D. R. Wiederin, F. G. Smith and B. W. Mattson, Metal speciation by means of micro-bore columns with direct-injection nebulizalion by inductively coupled plasma atomic emission spectroscopy, /. Chromatogr., 640,73,1993. 

Figure 25-2 shows the separation of four aromatics with a 2 mm micro-bore column using a flow of 220 J.l/min. This separation is quite good. 

M.J. Koenigbauer and M.A. Curtis, Use of Micellar Mobile Phases and Micro-Bore Column Switching for the Assay of Drugs in Physiological Fluids, J. Chromatogr., 71 111 (1988). 

Biological Fluids Micro-Bore Column-Switching HPLC Determination of Drugs... 

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