Improving chromatographic analysis of phenolic compounds

Abstract

Phenolic compounds are important chemicals and are applied in many fields. Moreover, they are found as contaminants in the environment. This research aimed to improve the chromatographic analysis of phenolic compounds and was divided into two parts. The first part focused on improving the separation of a mixture containing eighteen phenols using gas chromatography with derivatized cyclodextrin stationary phases. Results showed that all three cyclodextrin-based stationary phases, with different ring sizes, improved the separation of the mixture in comparison to polysiloxane OV-1701 stationary phase. The best separation was obtained from the small-size alpha-cyclodextrin with a capillary column of 15-meter long and a temperature program from 130 to 220 °C. Complete separation of all 18 phenols was obtained in 9.4 minutes. Some incomplete separations were observed when beta- and gamma-cyclodextrin stationary phases were used. The second part investigated optimum conditions for bisphenol A analysis using TLC combined with MALDI-TOF MS. These conditions included the use of graphene as a matrix, laser concentrations of 50% nitrogen, and a graphene-to-analyte ratio of 1:1. To validate the quantitative method, a suitable concentration range for BPA analysis using TLC combined with MALDI-TOF MS was determined to be 80 to 160 mM (or 18.3 to 36.5 µg), with an acceptable linear regression value (R2 = 0.9634).