Determination of Lipid Oxidation in Edible Oils by near Infrared Spectroscopy

1995 ◽  
Vol 3 (4) ◽  
pp. 219-225 ◽  
Author(s):  
Hitoshi Takamura ◽  
Noriko Hyakumoto ◽  
Naoko Endo ◽  
Teruyoshi Matoba ◽  
Tamako Nishiike
Keyword(s):  
Lipid Oxidation ◽  
Near Infrared ◽  
Edible Oils ◽  
Lipid Peroxide ◽  
Nir Spectroscopy ◽  
Second Derivative ◽  
Derivative Spectra ◽  
Highly Correlated ◽  
Second Derivative Spectra

The relationship between near infrared (NIR) second derivative spectra and lipid oxidation was investigated to develop a method for the determination of lipid oxidation in edible oils by NIR spectroscopy, using peroxide value ( POV) as the index of oxidation. Although several absorption peaks were found in the difference second derivative spectra of oxidised edible oils, the intensity of the peak at 2084 nm only was highly correlated to POV. In the spectra of purified hydroperoxides of methyl oleate and methyl linoleate, the intensity of the peak at 2084 nm was also highly correlated with POV, which demonstrates that the absorption is due to hydroperoxide. In addition, this peak shifted and weakened after reduction of hydroperoxide to hydroxide, which shows the absorption is specific for the hydroperoxyl group. These results suggest that 2084 nm is the key wavelength for lipid peroxide and can be used for the determination of lipid oxidation in edible oils.

Multi-wavelength analyses of second-derivative spectra for rapid determination of acetaminophen in serum.

1988 ◽  
Vol 34 (6) ◽  
pp. 1119-1121 ◽  
Author(s):  
B Dingeon ◽  
M A Charvin ◽  
M T Quenard ◽  
H Thome
Keyword(s):  
Phosphate Buffer ◽  
Rapid Determination ◽  
Turnaround Time ◽  
Second Derivative ◽  
Derivative Spectra ◽  
Multi Wavelength ◽  
Precision And Accuracy ◽  
Second Derivative Spectra ◽  
Method Of Extraction

Abstract Measurement of acetaminophen by analysis of the second derivative of its spectrum is specific and sensitive. The method of extraction and the use of just one phosphate buffer as reagent makes this method very convenient. Readings are reliable from 10 to 1500 mg/L. A turnaround time of 20 min makes this method well suited for emergency cases. Precision and accuracy of the method are presented. Results are not biased by interferences, not even from N-acetylcysteine.

scholarly journals NIR Absorbance Characteristics of Deoxynivalenol and of Sound and Fusarium-Damaged Wheat Kernels

2009 ◽  
Vol 17 (4) ◽  
pp. 213-221 ◽  
Author(s):  
Kamaranga H.S. Peiris ◽  
Michael O. Pumphrey ◽  
Floyd E. Dowell
Keyword(s):  
Absorption Spectra ◽  
Near Infrared ◽  
Peak Height ◽  
Second Derivative ◽  
Absorption Bands ◽  
Derivative Spectra ◽  
Nir Absorption ◽  
Second Derivative Spectra ◽  
Food Reserves ◽  
Wheat Kernels

The near infrared (NIR) absorption spectra of deoxynivalenol (DON) and single wheat kernels with or without DON were examined. The NIR absorption spectra of 0.5–2000 ppm of DON in acetonitrile were recorded in the 350–2500 nm range. Second derivative processing of the NIR spectra and spectral subtractions showed DON absorption bands at 1408 nm, 1904 nm and 1919 nm. NIR spectra of sound and Fusarium-damaged kernels were also acquired using two instruments. Subtraction of average absorption spectra and second derivative spectra were evaluated to identify different NIR signatures of the two types of kernel. Differences in peak height and positions of the NIR absorption bands of the kernels were noted. At 1204 nm, 1365 nm and 1700 nm, the differences were in the heights of the absorption peaks. Such differences may be attributed to changes in the levels of grain food reserves such as starches, proteins and lipids and other structural compounds. Shifts in absorption peak positions between the two types of kernels were observed at 1425–1440 nm and 1915–1930 nm. These differences may arise from other NIR active compounds, such as DON, which are not common for the two types of kernel. Since the NIR absorption of DON may have contributed to the shifts between sound and Fusarium-damaged kernels, this study indicates the potential for NIR spectrometry to evaluate Fusarium damage in single kernels based on the DON levels.

Discrimination of Commercial Natural Mineral Waters Using near Infrared Spectroscopy and Principal Component Analysis

1995 ◽  
Vol 3 (4) ◽  
pp. 203-210 ◽  
Author(s):  
Munehiro Tanaka ◽  
Ayako Shibata ◽  
Nobuyuki Hayashi ◽  
Takayuki Kojima ◽  
Hisashi Maeda ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Discriminant Analysis ◽  
Near Infrared ◽  
Principal Component ◽  
Component Analysis ◽  
Mineral Waters ◽  
Second Derivative ◽  
Natural Mineral ◽  
Derivative Spectra ◽  
Second Derivative Spectra

To obtain fundamental knowledge on the development of micro analyses for constituents in water, the discrimination of three varieties of commercial natural mineral water, ultra pure water and deionised water, was attempted using near infrared (NIR) spectroscopy. Both the original NIR spectra and their second derivatives were almost identical to each other for these five types of water and it was difficult to discriminate between their spectra visually. However, the use of discriminant analysis enabled the five kinds of waters to be distinguished. Principal component analysis for the second derivative spectra revealed that the independent variables of the discriminant analysis were identical with the wavelength regions affected by ionic hydration. For the discrimination of water, the original spectra were more suitable than the second derivative spectra because the baseline variation of the original spectra had the useful information for the analysis.

scholarly journals Simultaneous Determination of Metoprolol-Hydrochlorothiazide and Propranolol-Hydrochlorothiazide in Combined Formulations by Derivative Spectroscopy

1997 ◽  
Vol 80 (2) ◽  
pp. 325-330 ◽  
Author(s):  
Challapalli V N Prasad ◽  
Vipin Bharadwaj ◽  
Vidya Narsimhan ◽  
Rama T Chowdhary ◽  
Pyare Parimoo
Keyword(s):  
Simultaneous Determination ◽  
Second Derivative ◽  
Zero Crossing ◽  
Derivative Spectra ◽  
Derivative Spectroscopy ◽  
Naoh Solution ◽  
Compensation Technique ◽  
Second Derivative Spectra ◽  
Crossing Point

Abstract A derivative spectrophotometric procedure was established for simultaneous determination of propranolol HCI (PP) with hydrochlorothiazide (HTZ) and metoprolol tartrate (MTP) with HTZ in tablet preparations. The method uses first- and second-derivative spectra of tablet extract in 0.01 N NaOH solution. Ratios of analyte concentrations in the mixture were determined by the compensation technique. The zero-crossing point (ZCP) was also used to estimate the amounts of PP and HTZ in the formulations, and results were compared with those from the compensation technique. The results were found to be precise and free from interferences.

scholarly journals Simultaneous determination of compounds in Septalen® pellets by derivative spectrophotometry

2000 ◽  
Vol 65 (5-6) ◽  
pp. 339-344 ◽  
Author(s):  
Mirjana Medenica ◽  
Darko Ivanovic ◽  
Andjelija Malenovic
Keyword(s):  
Simultaneous Determination ◽  
Regression Coefficient ◽  
Correlation Coefficients ◽  
The Other ◽  
Second Derivative ◽  
Zero Crossing ◽  
Derivative Spectra ◽  
Second Derivative Spectra ◽  
Cetrimonium Bromide

In this paper, a second-derivative spectrophotometric method of assaying Septalen ? pellets (Krka, Novo Mesto, Slovenia), which contain lidocaine 1 mg, and cetrimoniumbromide 2mg, is described. Lidocaine, 2-(diethylamino)-N-(2,6-dimethyl- phenyl)-acetamide, is a local anesthetic with pronounced antiarhythmic and anticonvulsant properties. Cetrimoniumbromide, N,N,N-trimethyl-l-hexadecanaminium bromide, is a topical antiseptic and cleansing agent. Lidocaine was determined at 250 nm using the "zero crossing" technique because the signals of centrimonium bromide and the colour ingredient are zero at this wavelength. Cetrimonium bromide was determined by correction of the peak amplitude at 215 nm according to lidocaine. In choosing the optimal magnitudes for the simultaneous determination of both drugs, the following criteria were considered: (1) the linearity of the calibration graphs as given by the correlation coefficients, (2) the intercept, (3) the sensitivity as given by the regression coefficient, (4) the degree of interference in the derivative measurement by the presence of the other compound, as given by the relative percent error and by the relative recovery, and (5) the reproducibility, as given by the coefficient of variation, calculated by recording the second-derivative spectra.

Identification of Breast Carcinomatous Tissue by Near-Infrared Reflectance Spectroscopy

1994 ◽  
Vol 48 (2) ◽  
pp. 190-193 ◽  
Author(s):  
Joëlle Wallon ◽  
Shou He Yan ◽  
Jiashu Tong ◽  
Marc Meurens ◽  
Jules Haot
Keyword(s):  
Breast Cancer ◽  
Normal Tissue ◽  
Near Infrared ◽  
Nir Spectroscopy ◽  
Reflectance Spectroscopy ◽  
Near Infrared Reflectance ◽  
Tissue Sections ◽  
Derivative Spectra ◽  
Second Derivative Spectra ◽  
Cryostat Sections

NIR reflectance spectra of 110 cryostat sections of carcinomatous tissue and 114 cryostat sections of normal surrounding fibro-glandular tissue from 10 cases of breast cancer, identified by a classical pathology method, were scanned between 1100 and 2500 nm by a grating spectrometer in reflectance mode. Four wavelength intervals (1208–1242, 1746–1788, 2012–2048 and 2326–2368 nm) were found to be different for normal and carcinomatous tissues. In each interval, the second-derivative spectra of normal tissue showed a similar pattern with several characteristic peaks. In order to test the capacity of NIR spectroscopy in discriminating between normal and carcinomatous breast samples, 104 tissue sections from five additional cases were scanned prior to microscopic examination. The diagnostic prediction of NIR spectroscopy coincided exactly with the histology diagnosis for all the samples. Moreover, the presence of even a minute quantity of cancer infiltration can be detected by NIR spectroscopy, in total accordance with the microscopical observation. Therefore, the results of our experiments allow us to consider that NIR spectroscopy might become, with feasible improvements, an accurate, rapid, and reliable method for detecting breast cancer.

Fuzzy Optimal Associative Memory for Background Prediction of Near-Infrared Spectra

1996 ◽  
Vol 50 (1) ◽  
pp. 35-42 ◽  
Author(s):  
Busolo Wa Wabuyele ◽  
Peter De B. Harrington
Keyword(s):  
Associative Memory ◽  
Infrared Spectra ◽  
Plasma Glucose ◽  
Near Infrared ◽  
Second Derivative ◽  
Derivative Spectra ◽  
Near Ir ◽  
Near Infrared Spectra ◽  
Calibration Models ◽  
Second Derivative Spectra

A fuzzy optimal associative memory (FOAM) has been devised for background correction of near-infrared spectra. The FOAM yields improved predicted background scans for calculation of near-IR absorbance spectra of glucose in plasma matrices from single-beam data. The FOAM is an enhanced optimal associative memory (OAM) that uses a fuzzy function for encoding the spectra. The FOAM can predict a matching reference spectrum for a near-IR absorbance spectrum with low glucose absorbances by using second-derivative spectra. Glucose concentrations were predicted from calibration models furnished by partial least-squares (PLS). The FOAM stored reference spectra obtained from either water/phosphate buffer or plasma/glucose solutions. Both of these associative memories were evaluated. The standard error of prediction (SEP) for glucose concentration from an optimal PLS calibration model based on FOAM-corrected spectra was 0.60 mM for the water/phosphate buffer spectra. For FOAM-corrected spectra from plasma/glucose reference spectra, the SEP was 0.68 mM. The SEP of conventionally corrected double-beam second-derivative spectra was 0.81 mM. FOAM-corrected spectra generally furnish improved calibration models.

Development of a near infrared calibration model with temperature compensation using common temperature-difference spectra for determining the Brix value of intact fruits

2017 ◽  
Vol 25 (1) ◽  
pp. 26-35 ◽  
Author(s):  
Piyamart Jannok ◽  
Yoshinori Kamitani ◽  
Kazunori Hironaka ◽  
Michio Shibayama ◽  
Sumio Kawano
Keyword(s):  
Temperature Difference ◽  
Temperature Compensation ◽  
Near Infrared ◽  
Calibration Model ◽  
Second Derivative ◽  
Derivative Spectra ◽  
Fruit Species ◽  
Different Temperatures ◽  
The Common ◽  
Second Derivative Spectra

In order to create a calibration model with temperature compensation, the calibration method using the partial least squares regression based on the combined spectra measured at some different temperatures is promising. However, the method is time-consuming since it requires spectra acquisition at different temperatures. In addition, the sample quality may change during the period for the different temperature adjustment of samples. The spectra of the target fruit species of peaches, pears, and persimmons were measured at 25℃ using the interactance method. Spectra for 20℃ and 30℃ were created artificially using temperature-difference second derivative spectra from the 25℃-second derivative spectra. Then, the possibility of temperature-difference second derivative spectra of fruit(s) to create the correct 20℃ and 30℃ artificial second derivative spectra was evaluated. The temperature-difference second derivative spectra created from each target fruit species could be useful for each target fruit species while the common temperature-difference second derivative spectra created from the three target fruit species were useful for not only each target fruit species but also the other fruit species of apples. The calibration model for apples developed using the common temperature-difference second derivative spectra showed low standard error of performance and bias of 0.45°Brix and 0.09°Brix, respectively. The model could be applied well to the prediction sets of apples at 20℃, 25℃, and 30℃ with non-significant biases.

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