Improvement In 10,10′-dimethyl-9,9′-biacridinium Dinitrate Analytical Chemiluminescence Measurements By Use of Reactive Hydroxide Counterion Alkyltrimethylammonium Micellar Surfactants

The effect of alkyltrimethylammonium hydroxide micelle forming surfactants, such as hexadecyltrlmethylammonlum hydroxide, CTAOH, upon the lucigenin (Luc) chemiluminescent (CL) reaction system with biological reductants (l.e. fructose and glucose, ascorbic and uric acid) or hydrogen peroxide was evaluated. Results indicate that micellar CTAOH Is superior to a hexadecyltrlmethylammonlum chloride, CTAC, micellar medium with respect to Its ability to enhance the Integrated light Intensity observed from the Luc CL reaction with biological reductants. This Is due to enhanced micellar catalysis of the rate-limiting step of the Luc-reductant CL reaction In CTAOH micelles compared to that possible In CTAC. The substitution of CTAOH for CTAC as the micellar medium thus results In Improved sensitivity and precision for the Luc CL assay of biological reductants. For example, the lower detection limits for fructose using the Luc CL assay were 2.3, 7.0, and 9.8 mg/L for the procedure conducted In micellar CTAOH, micellar CTAC, and aqueous solution alone, respectively. With respect to the Luc-hydrogen peroxide CL system, both micellar CTAOH and CTAC have very similar effects upon the light yield observed. Since most Luc CL assays require basic conditions, the utilization of micellar CTAOH compared to CTAC offers the advantage of greater convenience since CTAOH in one solution can supply both the micelle-forming surfactant (CTA⁺, required for light Intensity enhancement) and the hydroxide Ion (required for efficient CL).