Systematic toxicological analysis by high-performance liquid chromatography with diode array detection (HPLC-DAD)

Area of Science:

• Analytical Chemistry
• Forensic Toxicology

Background:

• Photodiode array detectors (DADs) have significantly advanced in wavelength accuracy, resolution, sensitivity, linearity, and software.
• Modern DADs provide UV spectra comparable to conventional UV spectrometers, ensuring high reproducibility and inter-manufacturer agreement.

Observation:

• UV spectra exhibit high specificity related to substance structure, enabling the detection of subtle differences through similarity parameter calculations.
• Metabolites often share similar UV spectra with parent compounds, with predictable retention time shifts on reversed-phase columns.

Findings:

• HPLC-DAD, coupled with extensive UV spectra and retention parameter databases, is a highly efficient method for systematic toxicological analysis (STA).
• The technique excels in identifying drug metabolites due to spectral similarities and characteristic retention time variations.
• A routine procedure utilizing liquid-liquid extraction, protein precipitation, isocratic mobile phases, RP8 columns, and a database of 2682 compounds demonstrated method efficiency.

Implications:

• HPLC-DAD serves as a powerful tool for identifying a wide range of toxicologically relevant substances and their metabolites.
• The method's efficiency and specificity support its application in routine toxicological screening and analysis.
• Advancements in HPLC-DAD technology and database development enhance its utility in forensic and clinical toxicology.