A fiber-optic probe and an optical interface have been developed for drug dissolution testing with UV spectroscopy. A simple light cone was used to launch the light into the fiber; this increased the efficiency of light collection and reduced the dependence of the interface on the position of the source fiber. A principal component regression model was developed with the use of Fourier transformed spectra. The backgrounds and noise were reduced by the elimination of the first three terms and the use of the following 32 terms in the Fourier transforms. A commercial therapeutic drug, Sudafed Plus®, was tested, and the dissolution curves were very close to those obtained with a cuvette. The fiber-optic probe and the interface developed in this investigation can potentially be used in automated drug dissolution tests with spectroscopy.
Chris W. Brown and Jie Lin, "Interfacing a Fiber-Optic Probe to a Diode Array UV-Visible Spectrophotometer for Drug Dissolution Tests," Appl. Spectrosc. 47, 615-618 (1993)