[Determination of benzidine in cotton cloth by high performance liquid chromatography(HPLC)]

Area of Science:

• Analytical Chemistry
• Materials Science

Context:

• Benzidine is a known human carcinogen historically used in the dye industry.
• Azo dyes, common in textiles, can degrade to form benzidine.
• Accurate detection of benzidine in consumer products like cotton cloth is crucial for safety.

Purpose:

• To develop and validate a High-Performance Liquid Chromatography (HPLC) method for the quantitative determination of benzidine in cotton cloth.
• To establish a reliable analytical procedure for identifying and measuring benzidine derived from azo dyes in textile materials.

Summary:

• A method involving sodium dithionite reduction of azo dyes to benzidine, followed by diethyl ether extraction, was optimized.
• High-Performance Liquid Chromatography (HPLC) with a Hypersil ODS column and UV detection at 254 nm was employed for benzidine analysis.
• The method demonstrated good accuracy and recovery (average 84.7%), with determined benzidine levels in cotton cloth samples ranging from 86.9 to 120.8 µg/g.

Impact:

• Provides a validated analytical method for monitoring benzidine contamination in cotton textiles.
• Contributes to consumer safety by enabling the detection of potentially harmful dye degradation products.
• Highlights the importance of consistent reduction conditions for accurate benzidine quantification in complex matrices.