Near-Infrared Reflectance Spectroscopy for Noninvasive Monitoring of Metabolites
-
Abstract
An important class of substances in clinical chemistry are metabolites in body fluids, which are accessible by near-infrared spectroscopy without sample treatment using reagentless, fast and readily automated in vitro assays. Furthermore, noninvasive sensing systems are under development for the determination of blood glucose, especially for diabetic patients or for monitoring in intensive care and surgery. Near-infrared diffuse reflectance spectrometry of skin was employed allowing a certain tissue volume to be integrally probed. For calibration, the partial least-squares (PLS) algorithm was used either based on wide spectral intervals or using special spectral variable selection. Capillary blood glucose reference concentrations were obtained by finger pricking and an automated laboratory method (hexokinase/G6P-DH). Clear evidence is provided for the physical effect, as manifested by the spectral glucose absorptivities, underlying the individual single-person calibration models, which still require improvements in the methodology in the normo- and hypoglycemic concentration range. In extending the potential of noninvasive blood assays by infrared spectroscopy, a novel technique is presented for probing the intravascular fluid space by using fast spectral near-infrared measurements of skin tissue. The pulsatile blood spectrum can be derived from reflectance spectra of oral mucosa by Fourier analysis (near-infrared plethysmography). Future applications and prospects for noninvasive blood assays are discussed.
Copyright © 2000 by Walter de Gruyter GmbH & Co. KG
Artikel in diesem Heft
- IFCC WorldLab '99
- Markers of Endothelial Dysfunction
- Standardization and Quality Control of PCR Analyses
- Histochemical and Immunocytochemical Approaches to the Study of Oxidative Stress
- Sniffing out the Truth: Clinical Diagnosis Using the Electronic Nose
- Oncogenes and Thyroid Cancer
- Paraneoplastic Syndromes of the Nervous System
- Genetic Modifying Factors in β-Thalassemia
- The Genetics of Multiple Sclerosis
- Near-Infrared Reflectance Spectroscopy for Noninvasive Monitoring of Metabolites
- Ribozyme Gene Therapy for Autosomal Dominant Retinal Disease
- Oxidized Lipoproteins and Endothelium
- Experiences with External Quality Assessment (EQA) in Molecular Diagnostics in Clinical Laboratories in Germany
- Unravelling Genetic Data by Arrayed Primer Extension
- Evaluation of RNA Isolation Methods and Reference Genes for RT-PCR Analyses of Rare Target RNA
- IFCC WorldLab Daily News
Artikel in diesem Heft
- IFCC WorldLab '99
- Markers of Endothelial Dysfunction
- Standardization and Quality Control of PCR Analyses
- Histochemical and Immunocytochemical Approaches to the Study of Oxidative Stress
- Sniffing out the Truth: Clinical Diagnosis Using the Electronic Nose
- Oncogenes and Thyroid Cancer
- Paraneoplastic Syndromes of the Nervous System
- Genetic Modifying Factors in β-Thalassemia
- The Genetics of Multiple Sclerosis
- Near-Infrared Reflectance Spectroscopy for Noninvasive Monitoring of Metabolites
- Ribozyme Gene Therapy for Autosomal Dominant Retinal Disease
- Oxidized Lipoproteins and Endothelium
- Experiences with External Quality Assessment (EQA) in Molecular Diagnostics in Clinical Laboratories in Germany
- Unravelling Genetic Data by Arrayed Primer Extension
- Evaluation of RNA Isolation Methods and Reference Genes for RT-PCR Analyses of Rare Target RNA
- IFCC WorldLab Daily News
