acid for lanthanide complexes capable of cooperative binding elimination of coordinated water and multiple equilibria will result in an estimated 103 104 fold increase in sensitivity for the lanthanide luminescence method of bacterial spore detection 0045 fig2 b illustrates the aete process uv light is absorbed to excite the dpa molecule 18 in the combined form with the caged lanthanide from the state 1 u03c0 to 1 u03c0 an energy decay to the 3 u03c0 state of the dpa molecule 18 is followed by an energy transfer to the tb crown ether complex in the 5d4 state a characteristic energy decay or emission then follows from the 5d4 state in the tb crown ether complex to the 7fj 6 0 ground state the effect of chemical and biological interferents not originating from endospores has been studied extensively for this lanthanide luminescence detection scheme and applies to the proposed scheme as well it was found that no substance tested led to a false positive which would occur if the intrinsic tb luminescence is enhanced in the absence of bacterial endospores however false negatives occur when the signal of an endospore containing sample is strongly inhibited the main causes for luminescence inhibition are phosphate binding to tb and interferents that absorb strongly at the wavelength of excitation when such unknown interferents are present the analytical capability is compromised however if calibration curves are performed with interferents present then analytical ability remains.