Investigations of the effects of surface roughness on the utility of grazing-angle Fourier transform infrared reflection absorption spectroscopy (IRRAS) as a method for quantifying trace contamination of metal surfaces have been extended to acetaminophen, a model active pharmaceutical agent, on 316 stainless steel. The effects are more complicated than for the surfactant sodium dodecyl sulfate (SDS) on stainless steel; they include a strong surface-finish dependence of sensitivity and nonlinear behavior at surface loadings above ∼1–2 μg cm<sup>−2</sup>. Using data from samples in the loading range 0–0.5 μg cm<sup>−2</sup>, unbiased partial least squared calibrations can be readily achieved for individual surface finishes with detection limits of L<sub>D</sub> &ap; 0.15 &mu;g cm<sup>−2</sup>. However, as found for SDS on stainless steel, models built using data from samples of mixed surface roughness are more problematic.

PDF Article

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
Login to access OSA Member Subscription