Fourier transform infrared spectroscopy quantitative analysis

Additionally, a variety of analytical equipment and techniques that allow the examination of small- (and micro-) scale microbial cultures and their products have become available. Examples include near infrared and Fourier transform infrared spectroscopy, which offer the ability for in situ detection of specific compounds in fermentation broth [22]. However, sensitivity and the required sample volumes pose serious obstacles that still have to be overcome. Another alternative is offered by sensitive pyrolysis mass spectroscopy, which was demonstrated to be suitable for quantitative analysis of antibiotics in 5-pl aUquots of fermentation broth when combined with multivariate calibration and artificial neural networks [91]. The authors concluded that a throughput of about 12,000 isolates per month could be expected. Furthermore, standard chromatographic methods such as gas chromatography or high-performance liquid chromatography, possibly in combination with mass spectroscopy (MS) for detection, can provide simultaneous quantitative detection of many metabolic products. 

Mathematical modeling of the cure process coupled with the automation of various thermal analytical instruments and Fourier Transform Infrared Spectroscopy (FT-IR) have made possible the determination of quantitative cure and chemical reaction kinetics from a single dynamic scan of the reaction process. This paper describes the application of FT-IR, differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) in determining cure and reaction kinetics in some model organic coatings systems. 

The combination of gas chromatography (GC) with Fourier transform infrared spectroscopy (FTIR) has gradually become the important analytical tool for qualitative and quantitative analysis of complex mixtures. Numerous applications have been reported in previous reviews. Separation and identification of components in complex mixtures can be a daunting task. GC is the most common technique for separation of volatile and semivolatile mixtures. It is well accepted that when GC is coupled with spectral detection methods, such as MS, NMR, or FTIR spectrometry, the resulting combination is a powerful tool for the analysis of complex mixtures. 

The combination of chromatographic separation with Fourier transform infrared spectroscopy has significantly improved the analysis of complex mixtures [109]. In chromatography/ FT-IR systems, an infrared detector providing information on the structure of separated species is used instead of standard bulk chromatography detectors such as thermal conductivity, flame ionization, ultraviolet, or fluorescence these detectors can be used for quantitative analysis when the identities of the mixture components are known. 

Paxton and Randall [13] used Fourier transform infrared spectroscopy (FT-IR) to measure the concentration of bound ethylene in ethylene propylene copolymers in amounts down to 0.1 %. These polymers contained >95% propylene, with the ethylene units present as isolated entitles between two head-to-tail propylene units. These workers point out that most IR bands used for determining copolymer compositions are sensitive to sequences of both monomers. This IR method for compositional analysis can be calibrated if (a) known standards of similar constitution to the copolymers being analysed are available and (b) assignments and behaviour of the calibration bands are well established preferably the absorptivities of these bands should be relatively independent of the position of monomer units in the chain. Thus, quantitative IR analysis of copolymers depends primarily on the standards employed whose composition can be determined directly and reliably. Paxson and Randall [13] used C-NMR to provide such reference standards for the less time-consuming IR measurements because it is relatively inexpensive and easy to operate for copolymer analysis. They showed that an excellent correlation is obtained between C-NMR and IR results on a series of ethylene-propylene copolymers containing >95% wt% propylene. 

Prasad, A. (1998) A quantitative analysis of low density polyethylene and linear low density polyethylene blends by differential scanning calorimetry and Fourier transform infrared spectroscopy methods. J. Polym. Eng. Sci., 38, 1716-1728. 

Several spectroscopic techniques have been apphed to determine surfactants in cosmetics with different aims conventional infrared spectroscopy (IR) and nuclear magnetic resonance (NMR) for qualitative analysis near infrared spectroscopy (NIR) and attenuated total reflectance Fourier transformed infrared spectroscopy (ATR-FTIR) for quantitative analysis atomic absorption spectroscopy (AAS) to determine specific surfactants. Mass... 

An important tool for the fast characterization of intermediates and products in solution-phase synthesis are vibrational spectroscopic techniques such as Fourier transform infrared (FTIR) or Raman spectroscopy. These concepts have also been successfully applied to solid-phase organic chemistry. A single bead often suffices to acquire vibrational spectra that allow for qualitative and quantitative analysis of reaction products,3 reaction kinetics,4 or for decoding combinatorial libraries.5... 

NMR) [24], and Fourier transform-infrared (FT-IR) spectroscopy [25] are commonly applied methods. Analysis using mass spectrometric (MS) techniques has been achieved with gas chromatography-mass spectrometry (GC-MS), with chemical ionisation (Cl) often more informative than conventional electron impact (El) ionisation [26]. For the qualitative and quantitative characterisation of silicone polyether copolymers in particular, SEC, NMR, and FT-IR have also been demonstrated as useful and informative methods [22] and the application of high-temperature GC and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) is also described [5]. 

Brown, J. M. Elliott, J. J. "The Quantitative Analysis of Minerals by Fourier Transform Infrared (FT-IR) Spectroscopy", from Workshop on Application of IR Methods to the Study of Clay Minerals, Clay Mineral Society, 20th Annual Meeting, October 1, 1983, Buffalo, NY. 

Fourier-Transform Infrared (FTIR) spectroscopy as well as Raman spectroscopy are well established as methods for structural analysis of compounds in solution or when adsorbed to surfaces or in any other state. Analysis of the spectra provides information of qualitative as well as of quantitative nature. Very recent developments, FTIR imaging spectroscopy as well as Raman mapping spectroscopy, provide important information leading to the development of novel materials. If applied under optical near-field conditions, these new technologies combine lateral resolution down to the size of nanoparticles with the high chemical selectivity of a FTIR or Raman spectrum. These techniques now help us obtain information on molecular order and molecular orientation and conformation [1],... 

Fourier Transform Infrared (FTIR) spectroscopy methods have been reported for the quantitative analysis of a-tocopherol (Silva et ah, 2009) and total tocopherols, tocotrienols, and plastochromanol-8 (Ahmed et al., 2005). 

Tudor, A. M., Church, S. J., Hendra, P. J., Davies, M. C. and Melia, C. D. (1993). The qualitative and quantitative analysis of chlorpropanide polymorphic mixtures by near-infrared Fourier transform Raman spectroscopy. Pharm. Res., 10, 1772-6. [130, 132]... 

Fourier Transform Infrared (FT-IR) Spectroscopy With the introduction of commercial FT-IR spectrometers, the application of oil analysis by IR became relatively commonplace for production oil analysis laboratories. The mathematically intensive infrared data analysis techniques that were difficult or impossible to perform on the earlier IR systems became easy on these systems. In addition, quantitative analysis measurement techniques such as peak height, peak area, local baselines and more sophisticated matrix methods could be easily employed in the analysis, and the automation of lubricant analysis became commercially viable. 

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