• 제목/요약/키워드: Infrared spectra

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휴대용 근적외선 분광분석기를 이용한 비침투 혈당 측정 (Non-invasive Blood Glucose Measurement by a Portable Near Infrared (NIR) System)

  • 강나루;우영아;차봉수;이현철;김효진
    • 약학회지
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    • 제46권5호
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    • pp.331-336
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    • 2002
  • The purpose of this study is to develop a non-invasive blood glucose measurement method by a portable near infrared (NIR) system which was newly integrated by our lab. The portable NIR system includes a tungsten halogen lamp, a specialized reflectance fiber optic probe and a photo diode array type InGaAs detector; which was developed by a microchip technology based on the lithography. Reflectance NIR spectra of different parts of human body (finger tip, earlobe, and inner lip) were recorded by using a fiber optic probe. The spectra were collected over the spectral range 1100 ∼ 1740 nm. Partial least squares regression (PLSR) was applied for the calibration and validation for the determination of blood glucose. The calibration model from earlobe spectra presented better results, showing good correlation with a glucose oxidase method which is a mostly used standard method. This model predicted the glucose concentration for validation set with a SEP of 33 mg/dL. This study indicated the feasibility for non-invasive monitoring of blood glucose by a portable near infrared system.

PRELIMINARY STUDY ON NIR SPECTRA OF RETROGRADED STARCH

  • Terazawa, Yoko;Maekawa, Takaaki;Kawano, Sumio
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1515-1515
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    • 2001
  • Retrogradation of starch is one of important quality indexes for food based on starch such as rice. Therefore, in this research, possibility of near infrared spectroscopy to determine the degree of the retrogradation was examined. The degree of the retrogradation was indicated as the degree of geratinization analyzed by BAP(-amylase-pullulanase) method. 20 samples which have a wide range of the degree of the retrogradation were prepared and the NIR spectra of the samples were measured in reflectance mode with the NIR Systems 6500. In the correlation plots calculated from the 2nd derivative values of the MSC treated spectra and the degree of the geratinization, the major negative peaks of 1544 nm and 2258 nm, and the major positive peaks of 1460 nm, 1602 nm, 1766 nm and 2136 nm could be observed, indicating that NIR absorption at the positive peak wavelengths became strong while the absorption at the negative peak wavelengths became weak as the degree of the retrogradation increased. Because there is negative correlation between the degree of the retrogradation and the degree of the geratinization. As a result of MLR using the 2nd derivative values of the MSC treated spectra and the degree of the geratinization, good calibration equation which include 2258 nm as the first wavelength and 1764 nm as the second one could be obtained, indicating that NIR spectroscopy has a possibility to detect the retrogradation of starch. In order to find the assignment of the bands observed in the correlation plots, further study may be needed.

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Discrimination Analysis of Gallstones by Near Infrared Spectrometry Using a Soft Independent Modeling of Class Analogy

  • Lee, Sang-Hak;Son, Bum-Mok;Park, Ju-Eun;Choi, Sang-Seob;Nam, Jae-Jak
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.4106-4106
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    • 2001
  • A method to discriminate human gallstones by nea. infrared(NIR) spectrometry using a soft independent modeling of class analogy (SIMCA) has been studied. The fifty NIR spectra of gallstones in the wavenumber range from 4500 to 10,000 cm$\^$-1/ were measured. The forty samples were classified to three classes, cholesterol stone, calcium bilirubinate stone and calcium carbonate stone according to the contents of major components in each gallstone. The training set which contained objects of the different known class was constructed using forty NIR spectra and the test set was made with ten different gallstone spectra. The number of important principal components(PCs) to describe the class was determined by cross validation in order to improve the decision criterion of the SIMCA for the training set. The score plots of the class training set whose objects belong to the other classes were inspected. The critical distance of each class was computed using both the Euclidean distance and the Mahalanobis distance at a proper level of significance(${\alpha}$). Two methods were compared with respect to classification and their robustness towards the number of PCs selected to describe different classes.

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Electronic and Vibrational Spectroscopy of cis-Diisothiocyanato(1,4,8,11-tetraazacyclotetradecane)chromium(Ⅲ) Thiocyanate

  • Choi, Jong-Ha;Park, Yu-Chul
    • Bulletin of the Korean Chemical Society
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    • 제24권3호
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    • pp.384-388
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    • 2003
  • The emission and excitation spectra of $cis-[Cr(cyclam)(NCS)_2]NCS$ (cyclam = 1,4,8,11-tetraazacyclotetradecane) taken at 77 K are reported. The infrared and visible spectra at room temperature are also measured. The vibrational intervals due to the electronic ground state are extracted from the far-infrared and emission spectra. The ten pure electronic origins due to spin-allowed and spin-forbidden transitions are assigned by analyzing the absorption and excitation spectra. Using the observed transitions, a ligand field analysis has been performed to determine the bonding properties of the coordinated ligands in the title chromium(Ⅲ) complex. According to the results, it is found that nitrogen atoms of the cyclam ligand have a strong σ-donor character, while the NCS ligand has medium σ- and π-donor properties toward chromium(Ⅲ) ion.

The $2.5-5.0{\mu}m$ Spectra Atlas of Type 1 Active Galactic Nuclei with AKARI: Establishing the Black Hole Mass Estimator of Active Galactic Nuclei with Hydrogen Brackett Lines

  • 김도형;임명신
    • 천문학회보
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    • 제37권2호
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    • pp.80.1-80.1
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    • 2012
  • The $2.5-5.0{\mu}m$ spectrum of AGN was poorly understood due to the atmosphere effect beyond $2{\mu}m$. Nevertheless, the $2.5-5.0{\mu}m$ range includes several important lines, such as $Br{\beta}$ ($2.63{\mu}m$), $Br{\alpha}$ ($4.05{\mu}m$), PAH (3.3${\mu}m$) and many molecular or atomic lines. We compile $2.5-5.0{\mu}m$ spectra of 79 AGNs and QSOs from infrared camera (IRC) on AKARI infrared astronomy satellite. Our $2.5-5.0{\mu}m$ spectra will provide an access to full wavelength spectra of AGNs for the first time. Moreover, we present the Brackett line properties, FWHMs and luminosities, of AGNs. Using these Brackett line properties, we derive new black hole (BH) mass estimators. The new BH mass estimators using NIR hydrogen lines will be very useful to estimate BH mass of dusty red AGNs in the future.

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Interaction Between Barbiturate and Membrane Components

  • Yu, Byung-Sul;Jo, Seong-Bong;Kim, Chong-Kook;Hwang, Young-Sik
    • Archives of Pharmacal Research
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    • 제13권3호
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    • pp.246-251
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    • 1990
  • Intermolecular interaction between barbiturates and membrane components such as phospholipid and cholesterol were investigated on $^1$H-NMR spectra and infrared spectra. According to previous reports, barbiturates interacted with phospholipid through intermolecular hydrogen bonds. We also investigated thi observation using dipalmitoyl-phosphatidylcholine (DPPC) as phospholipid in deuterochloroform, and characterized quantitatively. Also, the observed drug could interact with cholesterol which is one of the major components of biomembranes through hydrogen bonds. It was the carbonyl groups of barbiturate and the hydroxyl group of cholesterol that formed hydrogen bond complex. In addition to spectroscopic studies, we investigated the direct effect of phenobarbital on lipid multibilayer vesicles, whose compositions were varied, by calorimetric method. Phenobarbital caused a reduction in the temperature of phase transition of vesicles. These studies may provided a basis for interpreting the mode of action of barbiturates.

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Monitoring Kinetics Using Near Infrared Spectra and Two-dimensional Correlation Spectroscopy

  • Berry, R. James;Ozaki, Yukihiro
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1282-1282
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    • 2001
  • Near Infrared (NIR) spectra has long been used in industry to monitor rates of reactions via calculation of analyte concentrations. However, the kinetic information is inherent in the data through spectral ratios. Two-dimensional correlation spectroscopy (2D-COS) is a spectral method that is based on changes (e.g. concentration) in time and is therefore uniquely suited for reaction monitoring. This method is especially useful in the understanding of how the reaction(s) proceeds. We will show the application of 2D-COS to synthetic kinetic data from different reaction orders to illustrate the method. We will then show application to real reactions of various orders. Finally, we will illustrate how 2D-COS will be of specific interest to developing optimized industrial reactions.

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Model Infrared Spectra for Evolving Red Supergiants

  • Suh, Kyung-Won
    • 한국우주과학회:학술대회논문집(한국우주과학회보)
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    • 한국우주과학회 1992년도 한국우주과학회보 제2권1호
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    • pp.13-13
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    • 1993
  • The space and ground based infrared spectra of red supergiants are modeled and arranged in order of their evolutionary status with their theoretical model Parameters. Because of their large amplitude pulsation, the observational data taken at different phases show wide discrepancies. The chemical compositions of the dust shells around red supergiants are affected by the nuclearreactions and dredge-up processes of the cental stars. Those processes aresensitiTelr dependent on the initial ma:ss, the initial chemical coMposition,and the evolutionarr status. Miras, infrared carbon stars, and OHAR starshaTe a close link in their evolution iii many aspects, i.e. the chemicalcomposition, the optical depths and the mass loss rates. The evolutionarytracks for the three classes of red super91iants on infrared Huo-color diagamhave been constructed.

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Double Resonance Spectra Involving Torsional Excited Levels and CO Stretch Band Transitions of $CD_3OH$

  • Choi, Sung-Eul
    • 한국광학회지
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    • 제6권2호
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    • pp.165-171
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    • 1995
  • Infrared-Radio frequency double resonance (IRRFDR) and Infrared-Microwave double resonance (IRMWDR) spectroscopy have been used to probe a level of A symmetry for $CD_{3}$OH. Double resonance spectra of $CD_{3}$OH have been investigated over the range of 940 to 1020 $cm ^{-1}$ . Twenty K-type doublet transitions have been observed in both the radio frequency region, which covers 50 MHz to 1 GHz, and the microwave region, which covers 8 GHz to 12 GHz. The results propose new assignments of infrared (IR) absorption transitions and far-infrared (FIR) laser emission lines. These involve torsional excited levels and CO stretch states. Measurements of the A state splitting have permitted the determination of the asymmetry splitting parameters $S^{o}$(n, K) and $^{co}$ (n, K) for (n, K)=(0.3) and (1.3)

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Infrared Absorption Spectroscopic Studies of ${\alpha},{\omega}$-Diphenylpolyenyl Anions with Odd Numbered Polyene Molecules

  • 김진열;김응렬;손대원
    • Bulletin of the Korean Chemical Society
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    • 제22권8호
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    • pp.833-836
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    • 2001
  • Infrared absorption spectra of $\alpha\omega-diphenylpolyenyl$, anions Ph(CH)nPh- (DPn-, n=7, 9, and 13) in the tetrahydrofuran-d6 solutions was measured in the range of 1700 and 1200 cm-1 . The infrared spectra obtained from anions (DPn) showed considerable difference from their neutral species (DPn); their intensities were enhanced at least two orders of magnitude stronger than their neutral species. The in-plane CH bending modes at 1464 and 1375 cm-1 are correspondingly strengthened with the chain length increased, but the C=C stretching at 1541 cm-1 is weakened and frequencies are not changed. We provide an IR evidence for the first time that the bond order or bond alternations of the anions (soliton) are different from those of radical anions (polaron) as well as neutral species.