Improved method for kinetic studies in microreactors using flow manipulation and noninvasive Raman spectrometry

Sergey Mozharov, Alison Nordon, David Littlejohn, Charlotte Wiles, Paul Watts, Paul Dallin, John M. Girkin

Research output: Contribution to journalArticle

61 Citations (Scopus)

Abstract

A novel method has been devised to derive kinetic information about reactions in microfluidic systems. Advantages g have been demonstrated over conventional procedures for a Knoevenagel condensation reaction in terms of the time required to obtain the data (fivefold reduction) and the efficient use of reagents (tenfold reduction). The procedure is based on a step change from a low (e.g., 0.6 mu L min(-1)) to a high (e.g., 14 mu L min(-1)) flow rate and real-time noninvasive Raman measurements at the end of the flow line, which allows location-specific information to be obtained without the need to move the measurement probe along the microreactor channel. To validate the method, values of the effective reaction order n were obtained employing two different experimental methodologies. Using these values of n, rate constants k were calculated and compared. The values of k derived from the proposed method at 10 and 40 degrees C were 0.0356 +/- 0.0008 mol(-0.3) dm(0.9) s(-1) (n = 1.3) and 0.24 +/- 0.018 mol-(0.1) dm(0.3) s(-1) (n = 1.1), respectively, whereas the values obtained using a more laborious conventional methodology were 0.0335 +/- 0.0032 mol(-0.4) dm(1.2) s(-1) (n = 1.4) at 10 degrees C and 0.244 +/- 0.032 mol(-0.3) dm(0.9) s(-1) (n = 1.3) at 40 degrees C. The new approach is not limited to analysis by Raman spectrometry and can be used with different techniques that can be incorporated into the end of the flow path to provide rapid measurements.

LanguageEnglish
Pages3601-3608
Number of pages8
JournalJournal of the American Chemical Society
Volume133
Issue number10
Early online date22 Feb 2011
DOIs
Publication statusPublished - 16 Mar 2011

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Spectrometry
Spectrum Analysis
Kinetics
Condensation reactions
Microfluidics
Rate constants
Data reduction
Flow rate

Keywords

  • electrospray mass spectrometry
  • total analysis systems
  • enzyme kinetics
  • microfluidic systems
  • time-scale
  • chip
  • reactors
  • device
  • assays
  • design

Cite this

Mozharov, Sergey ; Nordon, Alison ; Littlejohn, David ; Wiles, Charlotte ; Watts, Paul ; Dallin, Paul ; Girkin, John M. / Improved method for kinetic studies in microreactors using flow manipulation and noninvasive Raman spectrometry. In: Journal of the American Chemical Society. 2011 ; Vol. 133, No. 10. pp. 3601-3608.
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Improved method for kinetic studies in microreactors using flow manipulation and noninvasive Raman spectrometry. / Mozharov, Sergey; Nordon, Alison; Littlejohn, David; Wiles, Charlotte; Watts, Paul; Dallin, Paul; Girkin, John M.

In: Journal of the American Chemical Society, Vol. 133, No. 10, 16.03.2011, p. 3601-3608.

Research output: Contribution to journalArticle

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AU - Mozharov, Sergey

AU - Nordon, Alison

AU - Littlejohn, David

AU - Wiles, Charlotte

AU - Watts, Paul

AU - Dallin, Paul

AU - Girkin, John M.

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KW - electrospray mass spectrometry

KW - total analysis systems

KW - enzyme kinetics

KW - microfluidic systems

KW - time-scale

KW - chip

KW - reactors

KW - device

KW - assays

KW - design

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JF - Journal of the American Chemical Society

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