HPLC – CLND for the Analysis of Underivatized

HPLC–CLND for the Analysis of Underivatized Amino Acids

Evaluation of the chemiluminescent nitrogen detector for solubility determinations to support drug discovery.

Solubility measurements using chemiluminescent nitrogen detection (CLND) has advantages of reduced compound requirement and increased throughput compared to UV-spectrophotometric and HPLC-based measurements. CLND with direct flow injection was evaluated for the measurement of thermodynamic solubility to support drug discovery. The limit of quantitation (LOQ), accuracy, and day-to-day reproducib...

Performance of 2-Amino Tetraphenyl Porphyrin as Stationary Phase in RP-HPLC of Amino Acids

The search for new stationary phases has been one of the predominant concerns in high performance liquid chromatography (HPLC) in order to achieve better resolutions, longer column lives, and reduce the time of analysis. A chromatographic packing for separation of underivatized amino acids (AAs) were prepared by dynamically coating 2-amino tetraphenyl prophyrin (atpp) on a C-18 reversed-pha...

High-performance liquid chromatography coupled with chemiluminescence nitrogen detection for the study of ethoxyquin antioxidant and related organic bases.

The Chemiluminescent Nitrogen Detector (CLND) for use with high-performance liquid chromatography (HPLC) allows for the low-level detection of nitrogen-containing compounds with simple quantitation. The nitrogen selective detector's equimolar response (i.e., equal response for nitrogen independent of its chemical environment) allows for any nitrogen-containing compound to be quantitated as long...

Molecular characterization of organic nitrogen in cattle manure compost by size-exclusion HPLC with chemiluminescent nitrogen detection.

To characterize organic nitrogen present in cattle manure compost, a hot-water extract of the compost along with an acid-insoluble (humic acid-like) fraction either treated with alkali or laccase or untreated were separated by size-exclusion high-performance liquid chromatography (SE-HPLC). Nitrogen was then detected by chemiluminescent nitrogen detection (CLND), and humic acid-like substances ...