Chemiluminescent nitrogen

Supercritical fluid chromatography (SEC) was first reported in 1962, and applications of the technique rapidly increased following the introduction of commercially available instrumentation in the early 1980s due to the ability to determine thermally labile compounds using detection systems more commonly employed with GC. However, few applications of SEC have been published with regard to the determination of triazines. Recently, a chemiluminescence nitrogen detector was used with packed-column SEC and a methanol-modified CO2 mobile phase for the determination of atrazine, simazine, and propazine. Pressure and mobile phase gradients were used to demonstrate the efficacy of fhe fechnique. 

CLND Chemiluminescence nitrogen detector Pyro-chemiluminescence... 

Harrison, C.R., Lucy, C.A. (2002). Determination of zwitterionic and cationic surfactants by high-performance liquid chromatography with chemiluminescent nitrogen detection. J. Chromatogr. A 956(1-2), 237-244. 

Bhattachar, S.N., Wesley, J.A., and Seadeek, C. 2006. Evaluation of the chemiluminescent nitrogen detector for solubility determinations to support drug discovery. J. Pharm. Biomed. Anal. 41 152. 

Relative purity measurement and the relative purity-based reaction optimization have long been used in combinatorial synthesis. In order to make high-through-put purification a success, the yield-based optimization is essential. Chemiluminescent nitrogen detection (CLND) [4] with HPLC determines the quantitative yield after each reaction step during the library feasibility and rehearsal stages. The yield of each synthetic step provides guidance for the final library synthesis. 

Yan, B. Zhao, J. Leopold, K. Zhang, B. Jiang, G. Structure-Dependent Response of a Chemiluminescence Nitrogen Detector for Organic Compounds with Adjacent Nitrogen Atoms Connected by a Single Bond. Anal. Chem. 2007, 79, 718-726. 

Lane S, Boughtflower B, Mutton I et al. Toward single-calibrant quantification in HPLC. A comparison of three detection strategies Evaporative light scattering, chemiluminescent nitrogen, and proton NMR. Analytical Chemistry 77, 4354 365, 2005. 

Gradient RP-HPLC separation with 0.1% formic acid and methanol as mobile phase components (0.25 mL/min) combined either with ESI-time-of-flight [23] MS detection or with chemiluminescence nitrogen detection (CLND) was used to identify and, respectively, quantify illicit drugs in seized material without primary reference standards [24], The method exploits the accurate mass measurement provided by TOE MS, enabling the unequivocal identification of molecular formula of the unknown analyte, and the CNLD equimolar response to nitrogen. 

EM Fujinari, JD Manes. Nitrogen-specific detection of peptides in liquid chromatography with chemiluminescent nitrogen detector. J Chromatogr A 676 113-120, 1994. 

In LC/MS analysis of combinatorial libraries, the MS determines the product identity and its purity is determined by other on-line detection techniques such as UV, evaporative light scattering detection (ELSD), and chemiluminescent nitrogen detection (CLND).17-20 UV detection is used here to assess product purity based on the assumption of similar absorption coefficients at 214 nm for the desired product and the side-products. 

Fitch WL, Szardenings AK, Fujinari EM. Chemiluminescent nitrogen detection for HPLC an important new tool in organic analytical chemistry. Tetrahedron Lett 1997 38 1689-1692. 

Taylor EW, Qian MG, Dollinger GD. Simultaneous online characterization of small organic molecules derived from combinatorial libraries for identity, quantity, and purity by reversed-phase HPLC with chemiluminescent nitrogen, UV, and mass spectrometric detection. Anal Chem 1998 70 3339-3347. 

Nussbaum MA, Baertschi SW, Jansen PJ. Determination of relative UV response factors for HPLC by use of a chemiluminescent nitrogen-specific detector. J Pharm Biomed Anal 2002 27 983-993. 

FIGURE 10.2 Mechanism for the chemiluminescent nitrogen detector. R = any group attached to a nitrogen. 

Fujinary E, Manes JD, Bizanek R, Peptide content determination of crude synthetic peptides by reversed-phase liquid chromatography and nitrogen-specific detection with a chemiluminescent nitrogen detector, J. Chromatogr A, 743 85-89, 1996. 

Bizanek R, Manes JD, Fujinari E, Chemiluminescent nitrogen detection as a new technique for purity assessment of synthetic peptides separated by reversed-phase HPLC, Peptide. Res., 9(l) 40 44, 1996. 

Nitrogen a Dohrmann microcoulometric reactor being used in reductive mode was replaced with an Antek Model 771 pyroreactor which uses a chemiluminescent nitrogen detector. 

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