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 reproducibility of the detector were measured. Measurements made on CLND were compared to those obtained from UV spectrophotometry and HPLC. Based on the results obtained, it was concluded that the CLND performs satisfactorily for discovery stage thermodynamic solubility measurements.