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PubMed · 14987113

Nanoflow gradient generator for capillary high-performance liquid chromatography.

Kisaburo Deguchi·Shinya Ito·Shinji Yoshioka·Izumi Ogata·Akihiro Takeda
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Abstract

A novel method of generating a nanoflow gradient elution for a capillary high-performance liquid chromatography (HPLC) system has been developed. An important feature of this system is that any gradient (GR) profile generated by a conventional microflow GR pump can be asymptotically traced and converted as a corresponding nanoflow GR profile simply by using a 10-port switching valve with two injection loops installed. Consequently, it has been called an "asymptotic trace 10-port valve" (AT10PV) nanoflow GR generator. Performance of the AT10PV nanoflow GR generator was tested in the range of flow rates from 50 to 500 nL/min. The test demonstrated that the AT10PV nanoflow GR generator can asymptotically trace the original gradient profile with good reproducibility. A capillary HPLC system using the AT10PV nanoflow GR generator provides reasonably good repeatability of peak retention times on the chromatogram of the tryptic digest of a BSA sample, RSD of less than 0.3% at a flow rate of 200 nL/min. It also enables sequential running of a series of sample injections in the same manner as conventional analysis at microflow rates.

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AcetoneAcetonitrilesChromatography, High Pressure LiquidMicrofluidicsNanotechnologyReproducibility of ResultsSerum Albumin, BovineSolventsTime FactorsTrypsinJournal Article

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Kisaburo Deguchi, Shinya Ito, Shinji Yoshioka, Izumi Ogata, Akihiro Takeda. 2004-03-01. Nanoflow gradient generator for capillary high-performance liquid chromatography.. https://doi.org/10.1021/ac0350312

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