WAVELENGTH PAIR SELECTION FOR BACTERIAL ENDOSPORE DETECTION BY USE OFTERBIUM DIPICOLINATE PHOTOLUMINESCENCE

Two regression techniques, a multivariate technique and a subtracted c omponent technique, were applied to two-wavelength response functions of mixtures of terbium (III) dipicolinate and insoluble bacterial part icles. Two wavelength pairs were analyzed: a pair of neighboring wavel engths (450/490 nm) and a pair of widely spaced wavelengths (490/622 n m). The analysis shows that two emission-wavelength spectra from terbi um-treated endospores can be distinguished from the vegetative bacteri a spectrum above a limit of detection for endospores, which depends on the regression algorithm used to analyze the spectra. The subtracted component method for the neighboring wavelength pair had far lower lim its of detection than the other methods.