Photochemical detection in high-performance liquid chromatography and its application to cannabinoid analysis

Area of Science:

• Analytical Chemistry
• Chromatography
• Photochemistry

Background:

• High-performance liquid chromatography (HPLC) is a key analytical technique.
• Enhancing sensitivity and specificity in HPLC detection remains a challenge.
• Certain analytes lack inherent properties for sensitive detection.

Purpose of the Study:

• To introduce a novel on-line photochemical derivatization technique for HPLC.
• To improve the sensitivity and specificity of analyte detection.
• To demonstrate the application of this technique for cannabinoid analysis.

Main Methods:

• Utilizing a photochemical reactor with high-flux UV light post-HPLC column.
• Irradiating column eluent to induce reactions forming detectable products.
• Comparing chromatograms with and without UV irradiation for specificity.

Main Results:

• Photochemical derivatization significantly enhances detection sensitivity and specificity.
• Cannabinol (CBN) detection sensitivity improved to less than 1 ng.
• The method allows for the elimination of naturally fluorescent interfering compounds.

Conclusions:

• On-line photochemical derivatization is a powerful tool for improving HPLC analysis.
• This technique offers rapid, sensitive, and specific detection of analytes like CBN.
• The method has potential for detecting previously undetectable substances in various matrices, including body fluids.