Near-infrared Raman instrument for rapid and quantitative measurements of clinically important analytes

Abstract

Articles you may be interested inUltrasensitive near-infrared cavity ring-down spectrometer for precise line profile measurement Rev. Sci. Instrum. 81, 043105 (2010); 10.1063/1.3385675 Design and performance of a wide-bandwidth and sensitive instrument for near-infrared spectroscopic measurements on human tissue Rev. Sci. Instrum. 75, 5315 (2004); 10.1063/1.1818588 High Pressure FTIR/Raman Studies on Molecular Conformation of Proteins and Model Peptides AIP Conf. Quantitative analysis of corroded copper patina by step scan and rapid scan photoacoustic Fourier transform infrared spectroscopy Rev. Sci. Instrum. 74, 331 (2003); 10.1063/1.1517740 Quantitative diode laser absorption spectroscopy near 2 μm with high precision measurements of CO 2 concentration Rev. Sci. Instrum. 72, 4228 (2001);We present the use of a near-infrared ͑IR͒ laser Raman spectroscopy instrument to measure the concentrations of many important analytes at their clinically relevant levels in the simulated human serum. The Raman signal is generated by a 745 nm diode laser in a disposable waveguide capillary cell that contains a submicroliter sample. The Raman spectrum is acquired from the sample in 10 s. The major error in quantitative Raman spectroscopy caused by the variation in laser power, optical alignment, and capillary cell size from measurement to measurement is eliminated by normalizing the spectrum to the dominant water peak at 3350 cm Ϫ1 . Concentrations of glucose, acetaminophen, albumin, and other analytes are predicted using partial least squares ͑PLS͒ calibration. An effective multiple bandpass-filtering method was developed to enhance the signal of the desired analytes to interfering background ratio for improvement of PLS calibration accuracy. It is demonstrated that the accuracy of predicted concentrations for all analytes in the simulated human serum samples are highly acceptable for clinical diagnosis. The results promise the potential applications of the near-IR Raman instrument in medical practice.

Chemical concentration measurement in blood serum and urine samples using liquid-core optical fiber Raman spectroscopy

“…The mean concentration of BUN in this sample set was 17.3 mg͞dl, an order of magnitude lower than for most of the other analytes reported. As shown in (15) 10.5 4.1 ϫ 9.6 (10) Y 6.1 510-1500 TP 145 (7) 3.5 148 ϫ 182 (9) Y 0.7 610-1725 Albumin 83 (15) 4.7 87 ϫ 123 (17) Y 2.2 910-1800 CO 2 (mEq͞l) 2.3 (12) 1.9 1.9 ϫ 2.2 (10) 0 900-1800 BUN 1.5 (15) 3.3 1.6 ϫ 1.7 (14) 0.7 510-1800 TB 0.09 (16) 2.8 0.1 ϫ 0.13 (15) Y 0.9 960-1600 UUN 40.0 (4) 7.0 42.4 ϫ 53.0 (3) Y 1.8 550-1800 Creatinine 4.3 (17) 9.3 5.1 ϫ 6.8 (9) Y 3.4 550-1800 Globulin 110 (11) 4.1 --130 (11) 0.6 1000-1800 Glucose 8.8 (14) 5.3 3.8 15.4 (12) Y 2.2 510-1320 Triglyceride 11.5 (14) 6.1 8.0 18.0 (11) Y 2.2 510-1800 HDL* 11.9 (13) 1.5 3.4 12.1 (10) 0 510-1200 LDL*…”

“…14 Though it requires no preprocessing, the method is limited by relatively broad peaks that are hard to resolve when overlapped. NIR Raman spectroscopy, which is of interest in this paper, has also been used to predict chemical concentrations in blood serum samples 1,7,[15][16][17][18] and urine samples. 2,19,20 A major limitation, however, is the weakness of the Raman signal.…”

Discrete Wavelet Transform for Denoising Raman Spectra of Human Skin Tissues Used in a Discriminant Diagnostic Algorithm

“…[23] Also, an effective multiple bandpass filtering method has been performed in near-infrared Raman spectra to remove low-and highfrequency noise simultaneously. [24] Recently, some authors proposed the use of discrete wavelet transform (DWT) as an effective tool for denoising and background removal in Raman spectroscopy. [17][18][19]25] Wavelets have been shown to be effective as low-and high-frequency filters, revealing the middle-frequency Raman features.…”

A multimodal spectrometer for Raman scattering and near-infrared absorption measurement

“…In biomedical field, ethanol is also a common substance of abuse found in human blood (Qiu and Shao 2001). As an alternative motor fuel, ethanol-blended gasoline is deemed a good substitute for its ability to reduce air contaminants and its role in water quality monitoring (Niven 2005).…”