The Effect of Haematocrit on Measurement of the Mid-Infrared Refractive Index of Plasma in Whole Blood
The Effect of Haematocrit on Measurement of the Mid-Infrared Refractive Index of Plasma in Whole Blood
Recent advances suggest that miniaturised mid-infrared (MIR) devices could replace more time-consuming, laboratory-based techniques for clinical diagnostics. This work uses Fourier transform infrared spectroscopy to show that the MIR complex refractive index of whole blood varies across a range of haematocrit. This indicates that the use of an evanescent measurement is not sufficient to optically exclude the cellular content of blood in the MIR, as previously assumed. Here, spectral refractive index data is presented in two ways. First, it is given as whole blood with varying haematocrit. Second, it is given as the percentage error that haematocrit introduces to plasma. The maximum error in the effective plasma refractive index due to the haematocrit of healthy adults was 0.25% for the real part n and 11% for the imaginary part k. This implies that calibration measurements of haematocrit can be used to account for errors introduced by the cellular content, enabling plasma spectra and analyte concentrations to be indirectly calculated from a whole blood sample. This methodological advance is of clinical importance as plasma concentration of analytes such as drugs can be determined using MIR without the preprocessing of whole blood.
Bioanalytical validation, Biofluid analysis, Mid-infrared spectroscopy, Point-of-care sensing
Rowe, David
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Owens, Daniel
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Parker, Suzanne
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Faust, Saul
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Wilkinson, James S
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Mashanovich, Goran
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November 2021
Rowe, David
a0e0fe82-5e29-42b8-b370-5236a722f015
Owens, Daniel
14ffebb7-6124-4f61-89c1-907248d111b6
Parker, Suzanne
32cbbbb4-6d5f-4135-9f46-f6e3145b21a7
Faust, Saul
f97df780-9f9b-418e-b349-7adf63e150c1
Wilkinson, James S
73483cf3-d9f2-4688-9b09-1c84257884ca
Mashanovich, Goran
c806e262-af80-4836-b96f-319425060051
Rowe, David, Owens, Daniel, Parker, Suzanne, Faust, Saul, Wilkinson, James S and Mashanovich, Goran
(2021)
The Effect of Haematocrit on Measurement of the Mid-Infrared Refractive Index of Plasma in Whole Blood.
Biosensors, 11 (11), [417].
(doi:10.3390/bios11110417).
Abstract
Recent advances suggest that miniaturised mid-infrared (MIR) devices could replace more time-consuming, laboratory-based techniques for clinical diagnostics. This work uses Fourier transform infrared spectroscopy to show that the MIR complex refractive index of whole blood varies across a range of haematocrit. This indicates that the use of an evanescent measurement is not sufficient to optically exclude the cellular content of blood in the MIR, as previously assumed. Here, spectral refractive index data is presented in two ways. First, it is given as whole blood with varying haematocrit. Second, it is given as the percentage error that haematocrit introduces to plasma. The maximum error in the effective plasma refractive index due to the haematocrit of healthy adults was 0.25% for the real part n and 11% for the imaginary part k. This implies that calibration measurements of haematocrit can be used to account for errors introduced by the cellular content, enabling plasma spectra and analyte concentrations to be indirectly calculated from a whole blood sample. This methodological advance is of clinical importance as plasma concentration of analytes such as drugs can be determined using MIR without the preprocessing of whole blood.
Text
biosensors-11-00417-v2
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Accepted/In Press date: 23 October 2021
Published date: November 2021
Additional Information:
Funding Information:
Funding: The authors acknowledge funding from EPSRC (grants EP/N00762X/1,EP/N013247/1 and EP/V047663/1). The study was supported by the NIHR Southampton Clinical Research Facility and the NIHR Clinical Research Network Wessex.
Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Keywords:
Bioanalytical validation, Biofluid analysis, Mid-infrared spectroscopy, Point-of-care sensing
Identifiers
Local EPrints ID: 452063
URI: http://eprints.soton.ac.uk/id/eprint/452063
ISSN: 2079-6374
PURE UUID: 3e4390ec-7bfc-443c-b498-3b981b79c58e
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Date deposited: 10 Nov 2021 17:33
Last modified: 17 Mar 2024 03:30
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Author:
Daniel Owens
Author:
Suzanne Parker
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