Determination of Bisphenols Using Ultraviolet Spectroscopy

Bisphenols have a strong, unique, absorption at 277nm in the ultraviolet region of the spectrum. This absorption can be used to both identify and quantify the Bisphenol in aqueous solutions. Standard curves over the range from 0.2 to 20 ppm of Bisphenol A  in water and alcohol have r² values in the range of r² = 0.998 – 0.999. BPA extracted from various sources has been successfully detected. Filtering samples through Nylon and Cellulose Acetate (CA) syringe filters lead to large decreases in BPA in the filtrate, in some cases to levels not detectable using UV spectroscopy. Other filter materials cause less loss of Bisphenols. Similar results have been obtained with other representative Bisphenols. Concentration of dilute samples allows detection of Bisphenols by ultraviolet spectroscopy. GC-MS confirms the ultraviolet data.