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  • Liquid phase detection in the miniature scale. Microfluidic and capillary scale measurement and separation systems. A tutorial review
Title: Liquid phase detection in the miniature scale. Microfluidic and capillary scale measurement and separation systems. A tutorial review
Microfluidic and capillary devices are increasingly being used in analytical applications while their overall size keeps decreasing. Detection sensitivity for these microdevices gains more importance as device sizes and consequently, sample volumes, decrease. This paper reviews optical, electrochemical, electrical, and mass spectrometric detection methods that are applicable to capillary scale and microfluidic devices, with brief introduction to the principles in each case. Much of this is considered in the context of separations. We do consider theoretical aspects of separations by open tubular liquid chromatography, arguably the most potentially fertile area of separations that has been left fallow largely because of lack of scale-appropriate detection methods. We also examine the theoretical basis of zone electrophoretic separations. Optical detection methods discussed include UV/Vis absorbance, fluorescence, chemiluminescence and refractometry. Amperometry is essentially the only electrochemical detection method used in microsystems. Suppressed conductance and especially contactless conductivity (admittance) detection are in wide use for the detection of ionic analytes. Microfluidic devices, integrated to various mass spectrometers, including ESI-MS, APCI-MS, and MALDI-MS are discussed. We consider the advantages and disadvantages of each detection method and compare the best reported limits of detection in as uniform a format as the available information allows. While this review pays more attention to recent  more » « less
Award ID(s):
2003324
PAR ID:
10555435
Author(s) / Creator(s):
;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Analytica Chimica Acta
Volume:
1305
Issue:
C
ISSN:
0003-2670
Page Range / eLocation ID:
342507
Subject(s) / Keyword(s):
Microfluidic device Liquid chromatography Capillary electrophoresis Ion exchange chromatography Mass spectrometry
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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